Examine individual changes

'{{For|the song by King Crimson|Cat Food (song)}} [[File:Catdryfood.jpg|right|thumb|200px|Cat with a bowl of [[Pelletizing|pelleted]] cat person is cat hhahahahahahahahahahahaha food.]] [[File:Feral-kitten-eating-adult-cottontail-picks,d,chufmsmmsmmsmskskskksskskskkskskskskskksksowowiowowowowiiutjtjfjjsjajkalelrmmjfjcls,e,,ckoksndjia,enhduwolrkfrabbit.jpg|thumb|Kitten eating [[cottontail rabbit]].]] '''Cat food''' is food for consumption by [[cat]]s. Cats have specific requirements for their dietary nutrients.<ref>{{cite journal | doi = 10.2460/javma.2005.226.512 | last = Knight | first = A | year = 2005 | title = In defense of vegetarian cat food | journal = [[Journal of the American Veterinary Medical Association]] | volume = 226 | issue = 4 | pages = 512–3 | pmid=15742685}}</ref> Certain nutrients, including many vitamins and [[amino acid]]s, are degraded by the temperatures, pressures and chemical treatments used during manufacture, and hence must be added after manufacture to avoid nutritional deficiency.<ref>Howell E. ''Food Enzymes for Health & Longevity'' Woodstock Valley, CT, US: Omangod Press. xx. 1980.</ref><ref name="perry">[http://www.preciouspets.org/truth.htm] | Perry T. What's really for dinner? The truth about commercial pet food. The Animals' Agenda. 1996. Nov. - Dec.</ref> The amino acid [[taurine]], for example, which is found in meat, is degraded during processing, so synthetic taurine is normally added afterwards. Long-term taurine deficiency may result in retinal degeneration, loss of vision, and cardiac arrest. ==History== The idea of preparing specialized food for cats came later than for dogs (see [[dog biscuits]] and [[dog food]]). This was likely due to the idea that cats could readily fend for themselves. In 1837, a French writer Mauny de Mornay critiqued this idea: {{quote|text=It is... thought wrongly that the cat, ill-fed, hunts better and takes more mice; this too is a grave error. The cat who is not given food is feeble and sickly; as soon as he has bitten into a mouse, he lies down to rest and sleep; while well fed, he is wide awake and satisfies his natural taste in chasing all that belongs to the rat family.<ref>Mauny de Mornay, ''Livre de l'eleveur et du proprietaire d'animaux domestiques'' 1837 https://books.google.com/books?printsec=frontcover&dq=intitle:%22animaux+domestiques%22&lr=&as_drrb_is=b&as_minm_is=0&as_miny_is=1800&as_maxm_is=0&as_maxy_is=1880&cd=36&pg=PA287&id=tBkGwxXqxpgC&num=100&as_brr=1#v=onepage&q&f=false</ref>}} In 1844, another French writer{{Who|date=February 2015}} expanded on this idea: {{quote|text=Normally in the country no care is taken of a cat's food, and he is left to live, it is said, from his hunting, but when he is hungry, he hunts the pantry's provisions far more than the mouse; because he does not pursue them and never watches them by need, but by instinct and attraction. And so, to neglect feeding a cat, is to render him at the same time useless and harmful, while with a few scraps regularly and properly given, the cat will never do any damage, and will render much service.<ref>Nicolas Jean Baptiste Boyard, ''Manuel du bouvier et zoophile: ou l'art d'élever de soigner les animaux '' 1844 https://books.google.com/books?pg=RA2-PA328&dq=intitle:%22animaux+domestiques%22+chat&lr=&as_drrb_is=b&as_minm_is=0&as_miny_is=1800&as_maxm_is=0&as_maxy_is=1880&cd=49&id=ODpFAAAAYAAJ&num=100&as_brr=1#v=onepage&q=intitle%3A%22animaux%20domestiques%22%20chat&f=false</ref>}} He goes on to say that it is all the more unreasonable to expect a cat to live from hunting in that cats take mice more for amusement than to eat: "A good cat takes many and eats few". By 1876, Gordon Stables emphasized the need to give cats particular food: {{quote|text=If then, only for the sake of making (a cat) more valuable as a vermin-killer, she ought to have regular and sufficient food. A cat ought to be fed at least twice a day. Let her have a dish to herself, put down to her, and removed when the meal is finished. Experience is the best teacher as regards the quantity of a cat's food, and in quality let it be varied. Oatmeal porridge and milk, or white bread steeped in warm milk, to which a little sugar has been added, are both excellent breakfasts for puss; and for dinner she must have an allowance of flesh. Boiled lights are better for her than horse-meat, and occasionally let her have fish. Teach your cat to wait patiently till she is served—a spoiled cat is nearly as disagreeable as a spoiled child. If you want to have your cat nice and clean, treat her now and then to a square inch of fresh butter. It not only acts as a gentle laxative, but, the grease, combining in her mouth, with the alkalinity of her saliva, forms a kind of natural cat-soap, and you will see she will immediately commence washing herself, and become beautifully clean. (N.B.—If you wish to have a cat nicely done up for showing, touch her all over with a sponge dipped in fresh cream, when she licks herself the effect is wonderful.) Remember that too much flesh-meat, especially liver,—which ought only to be given occasionally,—is very apt to induce a troublesome diarrhoea (looseness). Do not give your pet too many tit-bits at table; but whatever else you give her, never neglect to let her have her ''two regular meals''.<ref>Gordon Stables,'' 'Cats': their points and characteristics, with Curiosities of cat life, and ...'' 1876 https://books.google.com/books?pg=PA371&dq=cat+food+%22cat+food%22&lr=&as_drrb_is=b&as_minm_is=0&as_miny_is=1850&as_maxm_is=0&as_maxy_is=1880&cd=11&id=iUUDAAAAQAAJ&num=100&as_brr=0#v=onepage&q=cat%20food%20%22cat%20food%22&f=false</ref>}} In the same year, an advertisement for [[Spratt's|Spratt]] (better known for making dog food) said that their cat food entirely superseded "the unwholesome practice of feeding on boiled horse flesh; keeps the cat in perfect health."<ref>ad for Spratt's https://books.google.com/books?id=5-ANAAAAQAAJ&pg=PP8&dq=cat+food+%22cat+food%22&lr=&as_drrb_is=b&as_minm_is=0&as_miny_is=1850&as_maxm_is=0&as_maxy_is=1880&num=100&as_brr=0&cd=26#v=onepage&q=cat%20food%20%22cat%20food%22&f=false</ref> And, in another book on cats, Stables recommended the company's food: {{quote|text=Attend to the feeding, and, at a more than one-day show, cats ought to have ''water'' as well as milk. I think boiled [[Lights (offal)|lights]], cut into small pieces, with a very small portion of bullock's liver and bread soaked, is the best food; but I have tried Spratt's Patent Cat Food with a great number of cats, both of my own and those of friends, and have nearly always found it agree; and at a cat show it would, I believe, be both handy and cleanly.<ref>Gordon Stable, ''The domestic cat'', 1876, 61 https://books.google.com/books?printsec=frontcover&dq=%22+%22+intitle:cat&lr=&as_drrb_is=b&as_minm_is=0&as_miny_is=1850&as_maxm_is=0&as_maxy_is=1880&cd=10&pg=PA61&id=30oDAAAAQAAJ&num=100&as_brr=1#v=onepage&q&f=false</ref>}} Spratt, which began by making dog biscuits, appears to also have been the first commercial producer of cat food. During the 19th century and early 20th centuries, meat for cats and dogs in London, frequently [[horse meat]], was sold from barrows (hand–carts) by itinerant traders known as ''Cats' Meat Men''.<ref name=":18">{{cite web | url=http://www.museumoflondonprints.com/image/68598/john-galt-cats-meat-man-c-1901 | title=Cats' Meat Man: c.1901 | publisher=Museum of London | accessdate=October 2, 2012}}</ref> == Natural diet == Cats are obligate [[carnivore]]s—that is, they are true carnivores and depend upon the nutrients present in animal flesh for their dietary needs. Even domesticated cats will relish freshly killed meat from rodents, rabbits, amphibians, birds, reptiles and fish, but cats are also opportunistic feeders and will readily take cooked food<ref>{{Cite web|url = http://www.timeforpaws.co.uk/blog/wild-cats/|title = Wild Cats Survive - Time for Paws - Time for Paws|website = Time for Paws|language = en-GB|access-date = 2016-03-08}}</ref> as well as dried cat food when offered, if that food is palatable. The natural diet of cats therefore does not include any vegetable matter, although cats have been known to eat certain plants and grasses occasionally, usually as an [[Vomiting|emetic]]. Cats cannot synthesize some essential nutrients required for survival, including the amino acids [[taurine]] and [[arginine]], so these nutrients must be sourced from fresh meat in the natural diet. Cats lack the specific physiology to extract nutrients efficiently from plant-based materials, and require a high protein diet, which is why high-energy meats from freshly killed prey are optimal foods. ==Commercial cat food== Most store-bought cat food comes in either dry form, also known in the US as ''kibble'', or wet canned form. Some manufacturers sell frozen raw diets and premix products to cater to owners who [[raw feeding|feed raw]]. ===Dry food=== [[File:Katzenfutter.JPG|left|thumb|Dry (extruded) cat food example]] Dry food (8–10% moisture) is generally made by [[Food extrusion|extrusion]] cooking under high heat and pressure. Fat may then be sprayed on the food to increase [[palatability]], and other minor ingredients, such as heat-sensitive vitamins, which would be destroyed in the extrusion process, may be added. Dry food is most often packed in multi-wall [[paper bag]]s, sometimes with a [[plastic film]] layer; similar bag styles with film laminates or coextrusions are also used. ===Wet food=== [[File:Canned Cat Food1.jpg|right|thumb|Wet (canned) cat food example (Fish flakes in jelly)]] In the United States, [[canning|canned]] or wet food (75–78% moisture) generally comes in aluminum or steel cans in 3 [[ounce|oz]] (85 g), 5.5 oz (156 g), and 13 oz (369 g) sizes. It is also sold in foil pouch form. ===Vegetarian or vegan food=== Even though cats are [[obligate carnivore]]s, there are [[Vegetarianism|vegetarian]] and [[veganism|vegan]] cat foods available. Vegetarian cat food must be fortified with nutrients such as [[taurine]] and [[arachidonic acid]] that cats cannot synthesize from plant materials.<ref name="nutrient requirements">Nutrient Requirements of Cats. National Academies Press. Pg 30. {{ISBN|978-0-309-03682-5}}</ref> Some vegetarian cat food brands in the USA are labeled by their manufacturers as meeting [[AAFCO]]'s Cat Food Nutrient Profile.<ref name="Evolution Canned Vegan Cat Food">{{cite web|url=http://store.nexternal.com/vegancats/evolution-canned-vegan-cat-food-p6.aspx |title=Evolution Canned Vegan Cat Food – Vegan Cats Online Store |publisher=Store.nexternal.com |accessdate=2014-08-10}}</ref><ref name="Evolution Vegan Cat Kibble">{{cite web|url=http://store.nexternal.com/vegancats/evolution-vegan-cat-kibble-p5.aspx |title=Evolution Vegan Cat Kibble – Vegan Cats Online Store |publisher=Store.nexternal.com |accessdate=2014-08-10}}</ref> === Low protein === Low protein diets are not as popular with consumers{{Fix|text=do you mean cats or their owners?}} than high protein diets.<ref name=":34">Buff P., et al. 2014. Natural Pet Food: A review of Natural Diets and their Impact on Canine and Feline Physiology. Journal of Animal Science. (92): 3781-3791</ref> Low protein diets are frequently associated{{clarify|date=December 2017}} with renal care formulas and other prescribed therapeutic diets.<ref name=":133">Cline M. 2016. Nutritional Management of Chronic Kidney Disease in Cats and Dogs. Today’s Veterinary Practise. 1(1): 1-9</ref> === Raw food === [[Raw feeding]] is providing uncooked ingredients to cats.<ref name=":8">{{Cite journal|last=Freeman, Lisa M.; Chandler, Marjorie L.; Hamper, Beth A.; Weeth, Lisa P|first=|date=2013-11-21|title=Current knowledge about the risks and benefits of raw meat–based diets for dogs and cats|url=|journal=Journal of the American Veterinary Medical Association|volume=243 | issue = 11 |pages=1549–1558|via=|doi=10.2460/javma.243.11.1549}}</ref> Most of the diet will consist of animal-based ingredients, though fruits, vegetables and supplements are often added.<ref name=":8" /> Commercial raw food is mainly sold in three formats: fresh, frozen and [[Freeze-drying|freeze-dried]].<ref name=":8" /> Thawing and rehydration are necessary before feeding frozen and freeze-dried food respectively. Many available commercial diets are AAFCO certified in meeting the nutrient requirements of the cat.<ref name=":8" /> Some diets may be formulated for all life stages or they can also be AAFCO certified for adult maintenance or growth and gestation/lactation.<ref name=":8" /> Many people feed their cats raw food believing that it mimics the prey diet that wild cats would consume. Firm believers in raw diets report that they bring health benefits such as a shiny coat, cleaner teeth, improved immunity, energy and body odors{{Fix|text=why is body odour a health benefit?}} to their cats, although no scientific evidence exists to prove these claims.<ref name=":8" />  Commercial raw diets can undergo [[Pascalization|High Pressure Pasteurization]] (HPP), a process which kills bacteria and pathogens, including [[salmonella]], using high water pressure.<ref name=":9">{{Cite journal|last=Higgins|first=Kevin|date=2010|title=Fresh, Safe Food For Fido|url=|journal=Food Engineering|volume=82|pages=17–18|via=PRIMO}}</ref> This technique is [[United States Department of Agriculture|USDA]] approved and allows raw food to remain uncooked while greatly improving its safety and shelf-life.<ref name=":9" /> However, every year, many commercial raw pet foods are recalled due to various bacterial contamination, implying that feeding raw comes with a risk.<ref name=":9" /> === Weight management === Weight control simply means ensuring an energy balance: energy in equals energy out. Weight gain means more energy is being consumed than is being expended in exercise and other functions. A weight management diet is designed to allow fewer calories to be consumed in a larger volume of food, allowing for less risk of an energy imbalance. But the cat needs to take enough exercise too.   Adult cats should be fed a diet that has been formulated for maintenance{{clarify|date=December 2017}}, while at the same time it should be fed according to preference{{Fix|text=whose?}} and body condition. Cats generally prefer to eat smaller meals more frequently, which tends to lead to less weight gain compared to cats that are fed free-choice food. Meanwhile, some cats adapt to free-choice feeding and can maintain normal body weight, with no weight gain.<ref name=":6" /> In general, indoor cats have less opportunity or need for exercise than outdoor cats; so indoor cats are much more prone to weight gain. For indoor cats, there are a variety of choices to promote exercise, including various cat toys designed to stimulate chase and play behaviours.<ref name=":6" /> Overall, if an adult cat cannot maintain normal body condition on a free-choice feeding diet, despite exercise levels, portion-controlled feeding is recommended. Many pet cats are fed energy-dense, high carbohydrate diets, which provide much more energy than needed. This is a major issue with indoor cats as it has been shown to lead to obesity. To prevent cats from becoming overweight, owners should be more inclined to implement weight control diets, which provide the cat with nutrient-dense, low energy ingredients.<ref>{{Cite journal|last=Spofford|first=N|date=2014|title=A moderate fat, low-energy dry expanded diet reduces gain in body condition score when fed as part of a post neutering weight-control regimen in growing pet cats|url=|journal=Journal of Nutritional Science|volume=3|pages=|via=}}</ref> Studies show that cats fed lower energy diets had significantly reduced incidence of obesity, as the typical indoor pet cat does not need more energy than their resting energy requirement. For an average cat weighing 10-11 pounds (about 5&nbsp;kg), they would have a resting energy requirement of 180-200 kcal/day.<ref>{{Cite journal|last=Montes de Oca|first=M|date=2017|title=Prediction equations for metabolizable and digestible energy in feline diets|url=|journal=Animal Feed Science and Technology|volume=|pages=|via=}}</ref> Along with energy input and output, specific nutrients can be important in weight control diets. Fiber is one important component in weight control, with various benefits. A source of soluble and fermentable fiber helps to increase the movement of digesta through the gut and decrease gastric emptying. This helps to increase satiety in cats, potentially decreasing feeding rates and voluntary energy consumption. Fermentable fiber promotes healthy mucosa and [[commensal bacteria]]l growth, and improved digestion/nutrient absorption. Prebiotic fibers like [[fructooligosaccharide]]s (FOS) and mannonoligosaccharides (MOS) decrease the number of pathogenic bacteria and increase the number of beneficial bacteria in the gut. They also help to maintain microbial balance and a healthy immune system. Fiber is fermented in the colon to produce short-chain fatty acids which can be used as an energy source. Fermentable fiber has been demonstrated to enhance general health and decrease inflammation.<ref name=":18" /> Furthermore, non-fermentable fiber is critical to the formation of well-formed stool, and has been known to increase diet bulk while decreasing caloric density. Insoluble fiber has been proposed to regulate appetite by releasing hormones that reduce hunger. Sources of fiber commonly added in weight management cat food include beet pulp, barley, [[psyllium]] and [[cellulose]].   Another nutrient important for weight control diets is protein and its component amino acids. Felines, being obligate carnivores, require a natural diet of strict{{clarify|date=December 2017}} animal products which consists of protein and fat (i.e. muscle, organs and animal tissue). Dietary protein supplies amino acids that can be utilized and metabolised as energy over{{clarify|date=December 2017}} fat when provided, even though protein is not stored in the body the same way as fat.<ref name=":6" /> Dietary fat is more efficiently converted to body fat than protein; if an animal is consuming more than its energy requirement and if the excess energy is provided by fat, more weight will be gained than if the excess calories are coming from protein.<ref name=":6" /> Dietary protein also improves satiety during feed, resulting in decreased overconsumption of food.<ref name=":6" /> The protein content of the diet is a key factor in building and maintaining lean body (muscle) mass, which is an important aspect of weight control. Lean body mass maintenance is regulated by protein intake, but more importantly is regulated by exercise. Limited protein and amino acids in the diet will limit lean body mass growth, but exercise or lack of exercise will allow growth or shrinking of muscle. Successful weight control involves maintenance of healthy adipose tissue levels, but most importantly maintenance of lean body mass. Lean muscle is the driver of basal energy metabolism and aids in the use of energy. When sufficient levels of fat are provided, fat will be used by the body as an energy source, but only when there are insufficient levels of protein.   An important amino acid that is incorporated many weight loss/weight control diets is [[L-carnitine]]. This is a vitamin-like substance that is found in animal protein, and is the only form{{Fix|text=of what?}} found in nature as well as being the only biologically active form. It can be found in ingredients commonly used in more commercial pet foods, but specifically weight management/weight loss diets. L-carnitine is involved in many biological pathways, more specifically fatty acid metabolism, allowing for the conversion of long-chain fatty acids into energy. The introduction of L-carnitine ensures rapid transport and oxidation of fatty acids as well as efficient usage of dietary fatty acids and protein. Supplementary L-carnitine is used more often in weight loss diets, since its benefits mainly involve fatty acid metabolism to control weight loss. However, since weight control is, in essence, a prevention stage in overall weight management, it still has value in weight control diets in preserving and building lean body mass and inhibiting the storage of excess dietary fat. The majority of studies focusing on supplementary L-carnitine use look at its benefits for weight loss, including its effect on metabolic rate and fatty acid oxidation.<ref>{{Cite journal|last=Center|first=SA|date=2012|title=Influence of dietary supplementation with (L)-carnitine on metabolic rate, fatty acid oxidation, body condition and weight loss in overweight cats|url=|journal=Cornell University: Department of Clinical Sciences, College of Veterinary Medicine|volume=7|pages=1012–1015|via=}}</ref> At the same time, these studies still show similar results that prove their{{clarify|date=December 2017}} effects of controlling fatty acid metabolism for weight control, to avoid the need for weight loss diets. ==Packaging and labeling== {{further|Pet food#Labeling and regulation}} In the United States, cat foods labeled as "complete and balanced" must meet standards established by the [[Association of American Feed Control Officials]] (AAFCO) either by meeting a nutrient profile or by passing a feeding trial. Cat Food Nutrient Profiles were established in 1992 and updated in 1995 by the AAFCO's Feline Nutrition Expert Subcommittee. The updated profiles replaced the previous recommendations set by the [[United States National Research Council|National Research Council]] (NRC). Certain manufacturers label their products with terms such as premium, ultra premium, natural and holistic. Such terms currently have no legal definitions. {{Citation needed|date=March 2010}} However, "While most of the food supplied comes from within the US, the FDA ensures that standards are met within our borders even when components come from countries with less stringent levels of safety or label integrity."<ref>{{cite web | url=http://petfoodtalk.com/catfoodreviews/#cat-food | title = Cat Food Reviews: The Pleasure of Their Company | publisher=petfoodtalk.com}}</ref> Dry cat food (kibble) is most often packed in multi-wall [[paper bag]]s, sometimes with a [[plastic film]] layer; similar bag styles with film laminates or coextrusions are also used. Wet cat food is often packed in [[aluminum can]]s or [[steel can]]s. Packaging regulations for cat food are often very similar to corresponding regulations for human foods. ==Energy requirement== The energy requirements for adult cats range from 60–70 kcal metabolizable energy/kg body weight (BW) per day for inactive cats to 80–90 kcal/kg BW for active cats. Kittens at five weeks of age require 250 kcal/kg BW. The requirement drops with age, to 100 kcal/kg BW at 30 weeks and to the adult requirement at about 50 weeks. Gestating cats require approximately 90–100 kcal/kg BW, up to 1.5 times the energy required of normal adult maintenance.<ref name=":5" /> Lactating cats require 90–270 kcal/kg BW depending on litter size and they require between 2 and 2.5 times the energy needed for normal adult maintenance.<ref name=":5">{{cite book |title=Nutrient requirements of cats |publisher=National Academy Press |location=Washington, D.C |year=1986 |pages=4–5 |isbn=0-309-03682-8 |url=https://books.google.com/books?id=UTArAAAAYAAJ |author=Subcommittee on Cat Nutrition, Committee on Animal Nutrition, Board on Agriculture, National Research Council.}}</ref> ==Nutrients and functions== [[Vitamin]] deficiencies can lead to wide-ranging clinical abnormalities that reflect the diversity of their metabolic roles. Twelve minerals are known to be essential nutrients for cats. Calcium and phosphorus are crucial to strong bones and teeth. Cats need other minerals, such as magnesium, potassium, and sodium, for nerve impulse transmission, muscle contraction, and cell signaling. Many minerals only present in minute amounts in the body, including selenium, copper, and molybdenum, act as helpers in a wide variety of enzymatic reactions.<ref name="CFNPFD">{{cite web | author=Subcommittee on Dog and Cat Nutrition (Committee on Animal Nutrition, Board on Agriculture and Natural Resources, Division on Earth and Life Studies) | year=2006 | url=http://www.nap.edu/catalog.php?record_id=10668 | accessdate=2007-03-08 | title=The Role of Vitamins and Minerals in the Diet for Cats | work=Nutrient Requirements of Cats and Dogs. {{ISBN|0-309-08628-0}}| publisher=[[United States National Research Council|National Research Council]] - [[National Academies]]}}</ref> The [[Cat food#CFNP|table below]] lists the AAFCO nutritional profiles for cat foods along with the roles of vitamins and minerals in cat nutrition according to the National Research Council. ===Diet and disease=== Further information: [[Cat skin disorders]] Many nutrients can cause a variety of deficiency symptoms in cats, and the skin is a vital organ that is susceptible to dietary changes in minerals, protein, fatty acids, and vitamins A and B.<ref name=":143">{{Cite journal|last=Watson|first=Tim D. G.|date=1998-12-01|title=Diet and Skin Disease in Dogs and Cats|url=http://jn.nutrition.org/content/128/12/2783S|journal=The Journal of Nutrition|language=en|volume=128|issue=12|pages=2783S–2789S|issn=0022-3166|pmid=9868266}}</ref><ref name=":93">{{cite book|title=Manual of Skin Diseases of the Dog and Cat|last1=Paterson|first1=Sue|date=2009|publisher=John Wiley & Sons, Incorporated|edition=2}}</ref><ref name=":104">{{cite journal|last1=Hendriks|first1=W|last2=Allan|first2=F|last3=Tarttelin|first3=M|last4=Collett|first4=M|last5=Jones|first5=B|date=2001|title=Suspected Zinc-Induced Copper Deficiency in Growing Kittens Exposed to Galvanised Iron|url=|journal=New Zealand Veterinary Journal|volume=49|issue=2|page=|pages=68–72|via=}}</ref> Cat’s show dietary inadequacies in their skin through excess or inadequate oil production, and skin toughening. This results in dandruff, redness, hair loss, greasy skin, and reduced hair growth.<ref name=":112">{{cite journal|last1=Shibani|first1=shetty|last2=Gokul|first2=s|date=2012|title=Keratinization and Its Disorders|url=|journal=Oman Medical Journal|volume=27|issue=5|page=|pages=348–357|via=}}</ref><ref name=":07">{{cite journal|last1=Watson|first1=Tim|date=1998|title=Diet and skin disease in dogs and cats|url=|journal=The Journal of Nutrition|volume=128|page=|pages=2717–2722|via=}}</ref> === Skin and coat diets === Good overall nutrition is needed along with a well balanced diet.<ref name=":143"/> If problems with a greasy and dull looking coat or flaky skin arise this could be signs of a greater internal issue.<ref name=":143" /> It is possible that the cat is not getting the proper nutrients in the proper quantities in their diet.<ref name=":143" /> This can be see more commonly with cats that eat diets that are of poorer quality.<ref name=":143" /> ==== Zinc ==== Zinc's connection to skin and coat health is due to its influence on regulating cellular metabolism.<ref name=":143" /> Zinc also supports proper immune function and suitable activity within the inflammatory response.<ref name=":143" /> Deficiencies result in disorders of the skin and poor immune functioning.<ref name=":19">{{cite journal|last1=Cummings|first1=J|last2=Kovacic|first2=J|date=2009|title=The ubiquitous role of zinc in health and disease|url=|journal=Journal of veterinary emergency and critical care|volume=19|issue=3|page=|pages=215–240|via=}}</ref> When zinc is supplemented in diets, skin scaliness was decreased.<ref name=":19" /> Dietary sources include poultry, red meat, and eggs. ==== Copper ==== One of the many functions of copper is to assist in production of connective tissue and the pigment melanin.<ref name=":23">{{cite book|title=Nutrient requirements of cats|date=1986|publisher=National Academies Press|edition=13}}</ref> A deficiency in dietary copper is also related to collagen abnormalities, hypopigmentation of the skin, and alopecia.<ref name=":35">{{cite book|title=Muller and Kirk's Small Animal Dermatology|last1=Miller|first1=W|last2=Griffin|first2=C|last3=Campbell|first3=K|last4=Muller|first4=G|date=2013|edition=7}}</ref> Sources for cats include liver and supplements in the forms of copper sulfate and cupric oxide.<ref name=":44">{{cite journal|last1=Baker|first1=D|last2=Czarnecki-Maulden|first2=G|date=1991|title=Comparative nutrition of cats and dogs|url=|journal=Annual review of nutrition|volume=11|issue=1|page=|pages=239–263|via=}}</ref> ==== Selenium ==== Selenium works with vitamin E as antioxidants to handle the free radicals that are damaging to the body and the skin.<ref>{{cite journal|last1=Bauer|first1=J|date=2001|title=Evaluation of nutraceuticals, dietary supplements, and functional food ingredients for companion animals|url=|journal=Journal of the American Veterinary Medical Association|volume=218|issue=11|page=|pages=1755–1760|via=}}</ref> Selenium also plays a role with other antioxidants to help maintain cell membranes which provides further protection from free radicals causing oxidative stress.<ref name=":35" /> Oxidative stress plays a role in development of skin diseases.<ref name=":55">{{cite book|title=Effects of serum vitamin E levels on skin vitamin E levels in dogs and cats|last1=Jewell|first1=D|last2=Yu|first2=D|last3=Joshi|first3=D|date=2002|publisher=WSAVA Congress}}</ref> Dietary sources of selenium are naturally occurring in selenomethionine and tuna.<ref name=":23" /><ref name=":44" /> ==== Fatty acids ==== Fatty acids are an important part of the cats diet, some are more important than others with respect to the cats diet and these are known as essential fatty acids.<ref name=":143" /> Essential fatty acids are nutrients that cats are unable to produce at all or in sufficient amounts to reach their needs.<ref name=":143" /> There are 3 essential fatty acids that should be included in a cats diets and they are: [[Alpha-Linolenic acid]], [[Linoleic acid]], and [[Arachidonic acid]].<ref name=":143" /><ref name=":64">{{cite journal|last1=Lenox|first1=C|last2=Bauer|first2=J|date=2013|title=Potential Adverse effects of Omega-3-Fatty Acids in Dogs and Cats|url=|journal=Journal of veterinary internal medicine|volume=27|issue=2|page=|pages=217–226|via=}}</ref> Alpha-Linolenic acid is an [[Omega-3 fatty acid|Omega–3 fatty acid]] that is important to cats as it aids in the maintenance of their skin’s water barrier.<ref name=":143" /><ref name=":64" /> As the water barrier is important to the cats skin, ingredients that are high in Alpha-Linolenic acid, such as flaxseed, should be included in the cats diet.<ref name=":64" /> Another source of Omega-3 s are in fish oil however, it is higher in [[Eicosapentaenoic acid]] (EPA) and [[Docosahexaenoic acid]] (DHA) which can be important for cats as they have anti-inflammatory properties.<ref name=":64" /> Linoleic acid is an example of an [[Omega-6 fatty acid]] that also helps with the health of the cat’s skin by maintaining the integrity of their epithelial tissues.<ref name=":143" /> Linoleic acid is commonly found in plant-based oils, an ingredient that is commonly used as a source of Linoleic acid is sunflower oil.<ref name=":07"/> Arachidonic acid is also essential to cats because they are unable to create it from linoleic acid due to an absence of the [[Delta-6-desaturase|Delta 6 desaturase]] enzyme.<ref name=":143" /> It’s important for their skin for the same reason as Linoleic acid and can be found in ingredients such as animal fat.<ref name=":143" /> ==== Vitamin A ==== [[Vitamin A]] is a crucial nutritional component in the maintenance of feline skin and coat health.<ref name=":74">{{cite book|title=Canine and Feline Nutrition: A Resource for Companion Animal Professionals|last1=Case|first1=L|last2=Daristotle|first2=L|last3=Hayek|first3=M|last4=Raasch|first4=M|date=2010|publisher=Elsevier Health Sciences}}</ref> In addition to its many other functions, vitamin A plays an important role in the keratinization of the skin, hair and nails along with assisting in the development of various epithelial tissues throughout the body.<ref name=":74" /> The cells making up the epithelial tissues of the skin, respiratory and gastrointestinal tracts rely on vitamin A to successfully complete the process of mitosis in order preserve these tissues and repair any damages.<ref name=":74" /> The mucous secreting cells of the respiratory and gastrointestinal epithelium also specifically require vitamin A to successfully produce a specialized protein referred to as mucoproteins which aid in maintaining the health of these tissues.<ref name=":74" /> Unlike most other mammals, the cat is unique in that they are unable to transform B-carotene to vitamin A and therefore explicitly require active forms of vitamin A which are only found in animal products.<ref name=":74" /> This difference in metabolism is due to very low levels of activity of the enzyme B-carotene 15, 15’ dioxygenase in feline species.<ref name=":74" /> The nutrient profiles developed by AAFCO currently advise a minimum of 3332 IU/kg of vitamin A on a dry matter basis included in adult diets and 6668 IU/kg in the diets of growing kittens as well as pregnant or lactating female cats.<ref name=":83">{{cite web|title=Association of American Feed Control Officials (AAFCO)|publisher=AAFCO|accessdate=15 November 2017}}</ref> Common ingredients which help to incorporate the proper levels of vitamin A into feline diets include various types of liver as well as fish oils.<ref name=":74" /> ====Vitamin E==== [[Vitamin E]] is an essential nutrient which needs to be included in the feline diet in order to protect the lipid components within cellular membranes of various tissues in the body.<ref name=":143" /> Vitamin E is able to accomplish this through working with selenium and acting as an antioxidant to prevent free radicals from interacting with these fatty acid membrane components, resulting in reduced levels of [[oxidative stress]].<ref name=":55" /> This is particularly important in the skin as various oxidative environmental components can have very damaging effects if not protected by vitamin E.<ref name=":55" /> The nutrient profiles developed by AAFCO currently advise a minimum dry matter inclusion of 40 IU/kg of vitamin E in the diet of cats throughout all stages of development.<ref name=":83" /> Lipid metabolism is also a major contributor of free radicals, leading to an increased dietary requirement of vitamin E as the levels of polyunsaturated fatty acids in the diet increase.<ref name=":143" /> Ingredients such as wheat germ as well as certain plant oils contain high levels of active vitamin E and are commonly added to feline diets which are carefully stored in order to prevent oxidative destruction of vitamin E prior to consumption.<ref name=":55" /> ==== B vitamins ==== ===== Biotin ===== [[Biotin]] can be provided in feline diets through the addition of cooked eggs, liver, milk, legumes or nuts.<ref name=":74" /> Microorganisms living in the gastrointestinal tracts of cats are also able to synthesize and supply an alternative source of biotin if proper nutritional requirements are met.<ref name=":74" /> Its main function in metabolism is to operate as a coenzyme for essential carboxylation reactions throughout the body1 however it has also been shown to aid in the management of certain skin diseases in cats.<ref name=":143" /> Biotin is recommended by AAFCO to be included in feline diets at a minimum level of 0.07&nbsp;mg/kg on a dry matter basis throughout all stages of development.<ref name=":83" /> ====Vitamin C==== Unlike humans, felines are able to utilize simple sugars glucose and galactose in a specialized pathway which occurs in the liver, referred to as the glucuronate pathway.<ref name=":74" /> This pathway ultimately produces the active form of vitamin C and maintains it at an adequate level, therefore it does not need to be separately included in their diet.<ref name=":74" /> ==== Low protein therapeutic diets and relation to the kidneys ==== Therapeutic diets with low protein have been adopted by a number of big pet food manufacturers with the goal of supporting renal health for cats with [[chronic kidney disease]] (CKD).<ref name=":133"/> Chronic kidney disease or CKD is a highly prevalent condition in the feline population and is most common in the aging and older domesticated feline.<ref>{{Cite journal|last=White|first=Joanna|last2=Malik|first2=Richard|last3=Norris|first3=Jacqueline|date=December 2011|title=Feline chronic kidney disease: Can we move from treatment to prevention?|url=https://ac-els-cdn-com.subzero.lib.uoguelph.ca/S1090023310004430/1-s2.0-S1090023310004430-main.pdf?_tid=47580fae-d386-11e7-b8bf-00000aacb35e&acdnat=1511796113_2f48733dae3b7ac230e730c28b172e1c|journal=The Veterinary Journal|volume=190|pages=217–322|via=Elsevier Science Direct}}</ref> It has been shown that the lifespan of cats experiencing CKD can be extended by as much as 2 years when receiving therapeutic diets rather than regular maintenance diets.<ref name=":133" /> The normal functions of the kidneys are to control a normal fluid balance and to excrete waste products from the blood into the urine.<ref name=":42">{{cite journal | last1 = Backlund | first1 = B. | last2 = Zoran | first2 = D. | last3 = Nabity | first3 = M. | last4 = Norby | first4 = B. | last5 = Bauer | first5 = J. | year = 2011 | title = Effects of dietary protein content on renal parameters in normal cats | url = | journal = Journal of Feline Medicine and Surgery | volume = 13 | issue = | pages = 698–704 | doi=10.1016/j.jfms.2011.05.019}}</ref> One of the biggest concerns associated to CKD is to reduce the amount of stress put on the kidneys to process and excrete nitrogenous wastes from the body.<ref>{{Cite journal|last=Hoffman|first=Jay|last2=Falvo|first2=Michael|date=September 2004|title=PROTEIN – WHICH IS BEST?|url=|journal=Journal of Sports Science and Medicine|volume=3|pages=118–130|via=}}</ref> Low protein diets are a good choice for cats experiencing CKD as it lowers the amount of nitrogenous waste in the body helping to decease the strain put on the kidneys.<ref name=":133" /> Nitrogenous wastes are produced by the body when [[amino acid]]s obtained from the digestion of protein are metabolized to make energy.<ref name=":53">{{cite journal | last1 = Laflamme | first1 = D. | last2 = Hannah | first2 = S. | year = 2012 | title = Discrepancy between use of lean body mass or nitrogen balance to determine protein requirements for adult cats | url = | journal = Journal of Feline Medicine and Surgery | volume = 15 | issue = 8| pages = 691–697 | doi=10.1177/1098612x12474448}}</ref> The exact level of protein that is needed for therapeutic CKD diets is unclear, as sufficient protein in needed for maintenance while still offering a lower nitrogen level for the kidneys.<ref name=":133" /> Low protein diets can be formulated as a wet or dry food, with the main difference being the moisture content.<ref name=":05">Association of American Feed Control Officials. Official Publication. Champaign, IL: Association of American Feed Control Officials, 2016</ref><ref name=":133" /> These diets are formulated specifically to support the kidneys and urinary tract and also to help prevent the progression of CKD.<ref name=":142">{{cite journal | last1 = Geddes | first1 = R.F. | last2 = Finch | first2 = N.C. | last3 = Syme | first3 = H.M. | last4 = Elliott | first4 = J. | year = 2013 | title = The Role of Phosphorus in the Pathophysiology of Chronic Kidney Disease | url = | journal = Journal of Veterinary Emergency and Critical Care | volume = 23 | issue = 2| pages = 122–133 | doi=10.1111/vec.12032}}</ref> There are certain dietary parameters that these diets follow on top of low protein such as low phosphorus, high energy density, a higher fat content and inclusion of omega-3 fatty acids to aid the kidneys in different ways.<ref name=":133" /><ref name=":152">{{Cite journal|last=Cline|first=Martha|date=March 2016|title=Nutritional Management of Chronic Kidney Disease in Cats and Dogs|url=http://todaysveterinarypractice.navc.com/wp-content/uploads/2016/05/2016-0304_ACVN-Nutrition.pdf|journal=Today's Veterinary Practice|volume=|pages=58–66|via=}}</ref> Formulating the diet to have low phosphorus is very important as restricting the amount in the diet has been proven to decrease the progression of CKD.<ref name=":133" /> The reason that plasma phosphorus concentration should be kept low for low protein therapeutic diets is because phosphorus can be deposited into soft tissues and become [[Mineralization (biology)|mineralized]] which can cause kidney damage.<ref name=":142" /> Formulating these diets with higher amounts of fat is important to make sure the food is palatable in the absence of protein and promote an increased caloric intake.<ref name=":133" /> The higher fat content will also spare the use of protein for energy and help decrease stress on kidney.<ref name=":53"/> This inclusion of higher fat content also increase the energy density of the food which is important for cats with decreased appetites.<ref name=":133" /> Omega-3 fatty acids are included in therapeutic diets because of their anti-inflammatory properties to aid the diseased kidneys.<ref>{{Cite journal|last=Pollen|first=Susan|date=2001|title=Renal disease in small animals: a review of conditions and potential nutrient and botanical interventions. (Renal Disease in Small Animals)|url=http://go.galegroup.com.subzero.lib.uoguelph.ca/ps/i.do?&id=GALE&#124;A80532261&v=2.1&u=guel77241&it=r&p=AONE&sw=w&authCount=1|journal=Alternative Medicine Review|volume=6|pages=46–61|via=}}</ref> ==== Low protein diets and relation to the liver ==== Low protein diets should not be fed to cats with the liver condition known as [[hepatic encephalopathy]] because severe protein restriction can be detrimental to animals with this condition.<ref name=":16">{{Cite journal|last=Lidbury|first=Jonathan|last2=Cook|first2=Audrey|last3=Steiner|first3=Jörg|date=2016|title=Hepatic encephalopathy in dogs and cats|url=http://onlinelibrary.wiley.com/doi/10.1111/vec.12473/epdf|journal=Journal of Veterinary Emergency and Critical Care|volume=26|pages=471–487|via=|doi=10.1111/vec.12473}}</ref> Cats with this condition should be fed a diet with high quality protein sources that have adequate amounts of the amino acids [[taurine]] and [[arginine]].<ref name=":16" /> === High energy diets === A high energy diet is generally high in [[fat]]. Compared to [[carbohydrate]]s and [[protein]], fat provides much more [[Calorie|energy]], at 8.5 kcal/g.<ref>The heats of combustion for glucose, sucrose, and starch are 15.57, 16.48 and 17.48 kJ/g respectively, or 3.72, 3.94 and 4.18 kcal/g.</ref> High energy diets generally have a fat content greater than 20% on a dry matter basis. A high energy diet is appropriate for cats who are undergoing growth, recovering from illness, are [[Pregnancy|pregnant]] or [[Lactation|lactating]], as their energy requirements are higher than otherwise.<ref>Hand, M. S. L., & Lon, D. (2000). Small animal clinical nutrition (No. SF 992. N88. L49 2000).</ref> A lactating or gestating cat requires a nutrient-dense and highly digestible diet to withstand the high levels of stress being placed on her body.<ref name=":6">{{Cite book|title=Canine and Feline Nutrition: A Resource for Companion Animal Professionals|last=Case, L.P., Daristotle, L.D., Hayek, M.G., and Raasch, M.F.|first=|publisher=Mosby Elsevier|year=2011|isbn=9780323066198|location=|pages=199–206|oclc=664112342}}</ref> These conditions are found in cat food that is formulated for growth, performance, or high energy during all life stages.<ref name=":6" /> To maintain a neutral energy balance and thus maintain body weight, energy intake should increase with energy expenditure.<ref>{{cite book|last1=Case|first1=Linda|last2=Daristotle|first2=Leighann|last3=Hayek|first3=Michael|last4=Foess Raasch|first4=Melody|title=Canine and Feline Nutrition: A Resource for Companion Animal Professionals|date=2011|publisher=Elsevier|page=59|edition=Third}}</ref> Studies that relate the number of meals offered to cats per day to their daily activity levels have shown conflicting results. It has been shown that cats offered four meals a day or a random number of meals a day have similar energy levels, greater than those fed only one meal per day.<ref name="swanson">{{cite journal|last1=Deng|first1=P|last2=Iwazaki|first2=E|last3=Suchy|first3=SA|last4=Pallotto|first4=MR|last5=Swanson|first5=KS|title=Effects of feeding frequency and dietary water content on voluntary physical activity in healthy adult cats|journal=J Anim Sci|volume=92|issue=3|pages=1271–1277|doi=10.2527/jas.2013-7235|year=2014}}</ref> It has been postulated that this increased energy level could be due to purported spikes in activity before being fed, known as food anticipatory activity.<ref name="swanson" /> Other studies on female cats have found that increasing the daily amount of food may actually decrease their daily activity levels.<ref name="maria">{{cite journal|last1=de Godoy|first1=Maria|last2=Ochi|first2=K|last3=de Oliveira Mateus|first3=LF|last4=et al.|title=Feeding frequency, but not dietary water content, affects voluntary physical activity in young lean adult female cats|journal=J Anim Sci|date=2015|volume=93|pages=2597–2601|doi=10.2527/jas.2014-8574}}</ref> The age, sex, and whether cats are intact or have been spayed/neutered are all factors controlling activity level.<ref name="detweiler">{{cite journal|last1=Detweiler|first1=Katelyn|last2=Rawal|first2=Samona|last3=Swanson|first3=Kelly|last4=de Godoy|first4=Maria|title=Physical activity level of female and male adult cats before and after running wheel habituation|journal=J Nutr Sci|date=2017|volume=6|page=17|doi=10.1017/jns.2017.19}}</ref> As cats age, there is evidence that their metabolic energy requirements may increase,<ref name="main"/> especially after 12 or 13 years old,<ref name="main">{{cite journal|last1=Laflamme|first1=Dorothy|title=Nutrition for Aging Cats and Dogs and the importance of Body Condition|journal=Vet Clin Small Anim|volume=35|pages=713–742|doi=10.1016/j.cvsm.2004.12.011|year=2005}}</ref> but other evidence suggests that metabolic energy needs are not dissimilar at different ages.<ref name="berm">{{cite journal|last1=Bermingham|first1=Emma|last2=Thomas|first2=David|last3=Morris|first3=Penelope|last4=Hawthorne|first4=Amanda|title=Energy requirements of adult cats|journal=British Journal of Nutrition|date=2010|volume=103|pages=1083–1093|doi=10.1017/S000711450999290X}}</ref> Furthermore, it has been shown that cats over 12 years old are more likely to be underweight than younger cats, so a high calorie diet may be appropriate to treat weight loss, and thus to maintain an appropriate body condition score.<ref name="main" /> Weight loss can occur when the cat expends more energy but does not increase its food energy intake.<ref>{{cite book|last1=Case|first1=Linda|last2=Daristotle|first2=Leighann|last3=Hayek|first3=Michael|last4=Foess Raasch|first4=Melody|title=Canine and Feline Nutrition: A Resource for Companion Animal Professionals|date=2011|publisher=Elsevier|pages=59|edition=Third}}</ref> It has also been demonstrated that as cats age, they are less able to digest and thus absorb dietary fats and proteins.<ref name="main" /> Pregnancy and lactation are strenuous periods on the female cat. During pregnancy a cat should gain 38% of their body weight by the time they are ready to give birth. It is recommended that a cat's diet should contain 4000 kcal ME per day<ref name="Pregnancy Cat Nutrition">{{cite journal|last1=Fantaine|first1=E|title=Food Intake and Nutrition During Pregnancy, Lactation and Weaning in the Dam and Offspring|journal=Reproduction in Domestic Animals|date=2012|volume=47|pages=326–330|doi=10.1111/rda.12102}}</ref> while pregnant; during lactation it is recommended that the cat consumes 240 - 354 kcal/ME / kg of body weight.<ref name="Pregnancy Cat Nutrition"/> Studies show that increasing the intake of food for a pregnant animal in order to help it gain weight can have negative effects.<ref name="Pregnancy Cat Nutrition"/> It is acknowledged that rather than increasing intake, feeding a highly energy dense food is a way to ensure that the female cat, or queen, receives adequate energy and nutrient requirements are met.<ref name="Pregnancy Cat Nutrition"/> It has been found that nutritional support consistent with the [[Energy homeostasis|resting energy requirement]] (RER) soon after surgery or the onset of illness decreases the [[mortality rate]] and the duration of hospitalization in cats.<ref name="corbee">{{Cite journal|last=Corbee|first=R. J.|last2=Kerkhoven|first2=W. J. S.|year=2014|title=Nutritional Support of Dogs and Cats after Surgery or Illness|url=https://www-cabdirect-org.subzero.lib.uoguelph.ca/cabdirect/abstract/20143162817?q=(title%3a(Nutritional+Support+of+Dogs+and+Cats+after+Surgery+or+Illness)+AND+sn%3a%222165-3356%22+AND+yr%3a2014)|journal=Open Journal of Veterinary Medicine|volume=4|pages=44–57|via=CAB Direct|doi=10.4236/ojvm.2014.44006}}</ref><ref name="perea">{{Cite journal|last=Perea|first=S. C.|year=2008|title=Critical Care Nutrition for Feline Patients|url=http://www.sciencedirect.com/science/article/pii/S1938973608000731?via%3Dihub|journal=Topics in Companion Animal Medicine|volume=23 | issue = 4 |pages=207–215|via=ScienceDirect|doi=10.1053/j.tcam.2008.08.001}}</ref><ref name="chan">{{Cite journal|last=Chan|first=D.|year=2009|title=The Inappetent Hospitalised Cat: Clinical approach to maximising nutritional support|url=http://journals.sagepub.com.subzero.lib.uoguelph.ca/doi/abs/10.1016/j.jfms.2009.09.013|journal=Journal of Feline Medicine and Surgery|volume=11|pages=925–933|via=Sage Journals|doi=10.1016/j.jfms.2009.09.013}}</ref> A recovering cat needs enough energy (calories), as well as more protein and fats.<ref name="corbee"/> Critical care diets are formulated to be highly [[Palatability|palatable]] and digestible, as well as high [[energy density]].<ref name="perea"/><ref name="chan"/> This limits the mass of food required to be consumed to meet the RER.<ref name="perea"/> This type of high energy diet has proven to be very important in the nutritional support of post-operative and ill cats.<ref name="corbee"/><ref name="perea"/><ref name="chan"/> ===Vegan and vegetarian diets=== Vegetarian or vegan cat food has been available for many years, and is targeted primarily at vegan and vegetarian pet owners. While a small percentage of owners choose such a diet based on its perceived health benefits, the majority do so due to ethical concerns.<ref name="wakefield"/> Despite this, most vegans who feed their cats a vegan diet believe that a vegetarian diet is healthier than a conventional diet.<ref name="wakefield"/> There is much controversy over feeding cats a vegetarian diet. While there is anecdotal evidence that cats do well on vegetarian food,<ref name="VT">[https://books.google.com/books?id=fwgAAAAAMBAJ&pg=PA90 Is a vegetarian diet right for your cat or dog] Vegetarian Times</ref> studies on commercial and homemade vegetarian cat foods have found nutritional inadequacies.{{citation needed|date=May 2016}} As obligate carnivores, cats require nutrients (including arginine, taurine, arachidonic acid, vitamin A, vitamin B12 and niacin) found in meat sources. Plant sources do not contain enough of these. Vegetarian pet food companies try to correct these deficiencies by adding synthetically produced nutrients.<ref name="VT"/> According to the [[United States National Research Council]], "Cats require specific nutrients, not specific feedstuffs."<ref name="nutrient requirements" /> Cats on a vegan diet can develop abnormally [[alkaline]] (high [[pH]]) urine as plant-based proteins are more alkaline than the meat-based foods which cats have evolved to eat. When the urine becomes too alkaline, there is an increased risk of formation of [[struvite]] (also known as magnesium ammonium phosphate) bladder crystals and/or stones. Calcium oxalate stones can also occur if the urine is too acidic. Such stones can create irritation and infection of the urinary tract and require veterinary treatment.<ref>{{cite web|url=http://www.veganhealth.org/articles/vegan_cats |title=Vegan Cats |publisher=Veganhealth.org |accessdate=2014-08-10}}</ref> Organizations that advocate vegan or vegetarian diets for people have split opinions regarding vegetarian or vegan cat food. The [[International Vegetarian Union]],<ref>[http://www.ivu.org/faq/animals.html Frequently Asked Questions – Animals] International Vegetarian Union</ref> the [[Vegan Society]]<ref>[http://www.vegansociety.com/html/animals/care/cats/ Cats] Vegan society</ref> and [[People for the Ethical Treatment of Animals|PETA]]<ref>[http://www.peta.org/mc/factsheet_display.asp?ID=34 Meatless Meals for Dogs and Cats] Peta media center factsheet</ref> are some of the organizations that support a vegan or vegetarian diet for cats. But the [[Vegetarian Society]] suggests people "consider carefully" and that many cats will not adjust to a vegetarian diet. They provide a list of necessary nutrients that would need to be supplemented, and recommend that those who want to try should consult a veterinarian or animal nutritionist.<ref>{{cite web | url = http://www.vegsoc.org/info/catfood.html | title = Cats – a vegetarian diet? | accessdate = 2008-01-05 | author = Vegetarian Society | work = "Information Sheet" | publisher = Vegetarian Society | deadurl = yes | archiveurl = https://web.archive.org/web/20080105093636/http://www.vegsoc.org/info/catfood.html | archivedate = 2008-01-05 | df = }}</ref> The [[Animal Protection Institute]] also does not recommend a vegetarian diet for cats, and cautions that dietary deficiencies may take months or years to develop and may be untreatable. They do not recommend relying on supplements, because they may not contain necessary co-factors and enzymes and have not been studied for long term implications.<ref>{{cite web | url = http://www.bornfreeusa.org/articles.php?p=361&more=1 | title = Selecting a Commercial Pet Food | accessdate = 2009-06-03 | author = Born Free/Animal Protection Institute | date = 2004-07-04 | publisher = Animal Protection Institute | archiveurl=https://web.archive.org/web/20090204120524/http://bornfreeusa.org/articles.php?p=361&more=1|archivedate=2009-02-04 }}</ref> The animal welfare organization [[American Society for the Prevention of Cruelty to Animals]], although suggesting a supplemented vegetarian diet for dogs,<ref>{{cite web | url = http://www.aspca.org/aspcablog/2007/06/nutrition-q-vegetarian-diets-for-dogs.html | title = Nutrition Q & A: Vegetarian Diets for Dogs | accessdate = 2008-01-05 | author = ASPCA | date = June 28, 2007 | work = ASPCA blog | publisher = ASPCA | deadurl = yes | archiveurl = https://web.archive.org/web/20071215134408/http://www.aspca.org/aspcablog/2007/06/nutrition-q-vegetarian-diets-for-dogs.html | archivedate = December 15, 2007 | df = }}</ref> recommends against vegetarian and vegan diets for cats.<ref>{{cite web | url = http://www.aspca.org/aspcablog/2007/08/pet-nutrition-q-vegan-diet-for-cats.html | title = Nutrition Q & A: Vegetarian Diets for Cats | accessdate = 2008-01-05 | author = ASPCA | date = August 9, 2007 | work = ASPCA blog | publisher = ASPCA | deadurl = yes | archiveurl = https://web.archive.org/web/20080401025015/http://www.aspca.org/aspcablog/2007/08/pet-nutrition-q-vegan-diet-for-cats.html | archivedate = April 1, 2008 | df = }}</ref> The Association of Veterinarians for Animal Rights (now [[Humane Society Veterinary Medical Association]]) accepts that a plant-based diet can be nutritionally adequate, but stated in August 2006 that such diets "cannot at this time be reliably assured".<ref name="vets assoc stance">[https://web.archive.org/web/20080516110747/http://www.avar.org/publications_position.asp#p27 "AVAR position statements: Vegan and Vegetarian Cat and Dog Food Diets"] Association of Veterinarians for Animal Rights</ref> This position was based on a 2004 study demonstrating that of both of the two commercially available vegetarian cat diets tested against the AAFCO standard were nutritionally deficient.<ref>{{cite journal | last = Gray | first = CM | last2 = Sellon |first2=RK |last3=Freeman |first3=LM | year = 2004 | title = Nutritional adequacy of two vegan diets for cats | journal = [[Journal of the American Veterinary Medical Association]]| volume = 225 | issue = 11 | pages = 1670–5 | doi=10.2460/javma.2004.225.1670 | pmid=15626215}}</ref> The formulation error in one of these diets was promptly identified and corrected.<ref name="autogenerated512">{{cite journal | last = Knight | first = A | year = 2005 | title = In defense of vegetarian cat food | journal = [[Journal of the American Veterinary Medical Association]]| volume = 226 | issue = 4 | pages = 512–3 | doi=10.2460/javma.2005.226.512 | pmid=15742685}}</ref> Nevertheless, it remains likely that formulation errors will result in nutritional deficiencies in a wide range of commercially available diets from time to time, whether meat-based, vegetarian or vegan. Hence, regular (at least, annual) veterinary checkups of all companion animals is recommended, and brands may be occasionally varied.<ref name="autogenerated512"/>{{Failed verification|date=April 2013}} Even when adequately supplemented, vegetarian diets may present other risks, such as urine acidity problems. While there are anecdotal reports linking a vegetarian diet with urinary tract problems, no documented case report or study exists.<ref name="wakefield"/>{{Unreliable source?|date=May 2016}} One vegan cat food manufacturer has stated that "because of the relative acidity of meat to vegetable protein, some vegan cats suffer from <nowiki>[Urinary tract problems]</nowiki>."<ref>[http://www.vegancats.com/veganfaq.php vegancats.com FAQ]</ref> A quarter of cat owners who feed their cats a vegetarian diet perceive [[feline lower urinary tract disease]] as a health risk of such a diet.<ref name="wakefield"/>{{Unreliable source?|date=May 2016}} In 2006, the first study of the health of a population of long-term vegetarian cats was published in the Journal of the American Veterinary Medical Association. Most of the cats were fed a commercially available vegan diet, though 35% were allowed outdoors. The study consisted of telephone questionnaires of the caregivers of 32 cats, and analysis of blood samples from some of the cats. The blood samples were tested for [[taurine]] and [[cobalamin]] deficiencies. Cobalamin levels were normal in all cats. Taurine levels were low in 3 out of 17 cats tested, but not low enough to be considered clinically deficient. 97% of the caregivers perceived their cats to be healthy, including those with low taurine levels.<ref name="wakefield">{{cite journal | last = Wakefield | first = LA | last2= Shofer |first2=FS |last3=Michel |first3=KE | year = 2006 | title = Evaluation of cats fed vegetarian diets and attitudes of their caregivers | url = http://www.vegepets.info/resources/Publications/Veg-cats-Wakefield-et-al-JAVMA-2006.pdf | journal = [[Journal of the American Veterinary Medical Association]]| volume = 229 | issue = 1 | pages = 70–3 | doi=10.2460/javma.229.1.70}}</ref>{{Unreliable source?|date=May 2016}} Formulation of a nutritionally adequate vegan cat diet has its limitations.<ref name=":52">{{cite journal | last1 = Knight | first1 = Andrew | last2 = Leitsberger | first2 = Madelaine | year = 2016 | title = Vegetarian versus Meat-Based Diets for Companion Animals | url = | journal = Animals | volume = 6 | issue = 9| page = 57 }}</ref> Recurring errors during formulation include insufficient protein content, insufficient calcium and phosphorus, along with an unbalanced calcium to phosphorus ratio which strays from the ideal range of 0.9:1 to 1.1:1.<ref name=":52" /><ref>Barrette, D. (1988). Calcium and phosphorus for cats and dogs. ''The Canadian Veterinary Journal = La Revue Vétérinaire Canadienne,29''(9), 751-2.</ref> This is in addition to commonly occurring deficiencies of taurine, arachidonic acid, sodium, vitamin A, vitamin B12 as well as trace minerals.<ref name=":52" /> The reason for these dietary essential nutrients can be found in the [[Cat#Physiology|physiology]] section of the [[Cat|Cat page]]. Protein and fat content in a vegan cat diet can be balanced by the inclusion of tofu and yeast.<ref>Pitcairn, R., & Pitcairn, Susan Hubble. (1982). Dr. Pitcairn's complete guide to natural health for dogs & cats / by Richard H. Pitcairn and Susan Hubble Pitcairn ; (illustrations by Franc Fretz). Emmaus, Pa. : Rodale Press, 1982</ref> Over the counter supplementation of vitamins and minerals in some cases may not meet nutrient requirements, as they come in varying amounts.<ref>Remillard, R. (2008). Homemade Diets: Attributes, Pitfalls, and a Call for Action. Topics in Companion Animal Medicine, 23(3), 137-42</ref> As vegan diets are mainly derived from plant sources, some vitamins and minerals may be deficient, as plant sources do not provide adequate quantities. For instance, plant materials do not provide the preformed vitamin A which cats cannot synthesize, therefore supplementation is needed.<ref name=":03">{{cite journal | last1 = Schullerlevis | first1 = G. | last2 = Mehta | first2 = P. | last3 = Rudelli | first3 = R. | last4 = Sturman | first4 = J. | year = 1990 | title = IMMUNOLOGICAL CONSEQUENCES OF TAURINE DEFICIENCY IN CATS | url = | journal = Journal Of Leukocyte Biology | volume = 47 | issue = 4| pages = 321–331 }}</ref> As mentioned previously, arginine is a dietary requirement of cats, as it plays a critical role in bodily functions (refer to the [[Cat#Physiology|physiology]] section in the Cat page). Some ingredients of vegan cat diets that provide arginine, are pumpkin seed, almond, soya flour, lentil seeds and oat flakes (see table one).[https://www.researchgate.net/profile/Katarina_Babinska/publication/7562990_Health_benefits_and_risks_of_plant_proteins/links/0f31752f800b879c05000000.pdf <nowiki>[1]</nowiki>] The arachidonic acid added to cat foods typically comes from animal-based sources.<ref name=":13">{{cite journal | last1 = Gray | first1 = C. | last2 = Sellon | first2 = R. | last3 = Freeman | first3 = L. | year = 2004 | title = Nutritional adequacy of two vegan diets for cats | url = | journal = Journal of the American Veterinary Medical Association | volume = 225 | issue = 11| pages = 1670–5 | doi=10.2460/javma.2004.225.1670}}</ref> In vegan cat diets, arachidonic acid can be added by including algal biomass or seaweed;<ref name=":13" /> but too much seaweed can be detrimental, as it may contain enough [[selenium]] to be toxic.<ref name=":13" /> A vitamin D3 source, [[lanolin]], a constituent of sheep's wool, is often used to provide that vitamin.<ref name=":62">Vegan-friendly vitamin D.(abstracts). (2012). ''Prepared Foods,'' ''181''(6), 130.</ref> However, due to its animal origin this would not be appropriate for supplemental use in a vegan cat diet so a synthetic form of vitamin D3 is required.<ref name=":62" /> Vegan vitamin D3 can be synthesized by combining lichen, chicory extract and chamomile extract.<ref>Vegan Vitamin D3. (2015). ''Nutraceuticals World,'' ''18''(7), 68.</ref> Some vegan sources with high [[niacin]] content are Brewer's yeast, oats, wheat flours, sunflower seeds and sesame seeds.<ref name="usda">{{cite web|url=https://ndb.nal.usda.gov/ndb/nutrients/report/nutrientsfrm?max=25&offset=0&totCount=0&nutrient1=406&nutrient2=&nutrient3=&subset=1&fg=13&fg=1&fg=15&fg=17&fg=10&fg=5&fg=2&fg=11&sort=c&measureby=g|title=Niacin content per 100 grams; select food subset, abridged list by food groups|date=17 January 2017|publisher=United States Department of Agriculture, Agricultural Research Service, USDA Branded Food Products Database v.3.6.4.1|accessdate=23 January 2017}}</ref> AAFCO requires cat food to have 60&nbsp;mg of niacin per kg of cat food on a dry matter basis.<ref>{{Cite web|url=http://www.aafco.org/Portals/0/SiteContent/Regulatory/Committees/Pet-Food/Reports/Pet_Food_Report_2013_Midyear-Proposed_Revisions_to_AAFCO_Nutrient_Profiles.pdf|title=AAFCO Methods for Substantiating Nutritional Adequacy of Dog and Cat foods|first=|date=2014|publisher=AAFCO|archive-url=|archive-date=|dead-url=|access-date=}}</ref> Taurine can be biosynthesized or can be obtained in the diet by eating animal sources for food or algae.<ref name=":10">{{Cite journal|last=HUXTABLE|first=R. J|date=1992|title=Physiological Actions of Taurine|url=http://physrev.physiology.org.subzero.lib.uoguelph.ca/content/physrev/72/1/101.full.pdf|journal=American Physiological Society|volume=72|pages=101–163|via=|doi=10.1152/physrev.1992.72.1.101}}</ref> For cats, taurine is an essential amino acid as they cannot biosynthesize it from the amino acids methionine or cysteine; so they must obtain it [[endogenous]]ly.<ref name=":03"/> Enough synthetic taurine must be added to a vegan cat diet, as plant sources do not have taurine.<ref name=":10" /> (refer to the [[Cat#Physiology|physiology]] section on the Cat page). === Low protein diets === Protein content between cat foods can vary anywhere from a low protein content of 26% to a content as high as 50% or above.<ref name=":34"/> The [[National Research Council (United States)|National Research Council]] (NRC) recommends protein content for cat diets is to be around 20% for adult maintenance and 21.3% for growth and reproduction <ref>National Research Council Ad Hoc Committee on Dog and Cat Nutrition. Nutrient Requirement of Dogs and Cats. Washington (DC): Academics Press, 2006</ref> The [[Association of American Feed Control Officials]] (AAFCO) recommendations however suggest a higher protein level of 26% for adult maintenance and 30% for growth and reproduction.<ref name=":05"/> Cats are obligate carnivores and require protein in their diet as an important component in energy metabolism and maintenance of lean body muscle.<ref name=":42"/><ref name=":53"/> Cats are greatly adapted to a high protein diet since they utilize protein as their main energy source, keeping carbohydrate utilization very minimal.<ref name=":42" /> In addition, cats will continue to metabolize protein even through protein deficiency by catabolizing lean body muscle.<ref name=":42" /><ref name=":53" /> More specifically cats like most mammals, require the appropriate dietary amino acid balance to supply the essential amino acids, which are used for a multitude of body functions.<ref name=":42" /> It is crucial for low protein diets to meet AAFCO recommendations to ensure nutrient requirements are met. In general, lower protein diets tend to consist of a greater carbohydrate content, which means a potentially higher glycemic response in cats.<ref name=":63">Farrow H.A, et al. 2013. Effect of Dietary Carbohydrate, Fat, and Protein on Postprandial Glycemia and Energy Intake in Cats. J Vet Intern Med. 27: 1121-1135</ref> [[Glycemic]] response refers to the response of glucose concentrations in the blood after a meal.<ref name=":63" /> Hexokinase is the enzyme cats use for metabolizing glucose because they do not possess the more efficient enzyme glucokinase.<ref name=":42" /> Cats are susceptible to high prolonged postprandial glucose and insulin periods with high glucose peaks, resulting from the carbohydrate content of the diet.<ref name=":63" /><ref name=":73">{{cite journal | last1 = de-Oliveira | first1 = L. | last2 = Carciofi | first2 = A. | last3 = Oliveira | first3 = M. | last4 = Vasconcellos | first4 = R. | last5 = Bazolli | first5 = R. | last6 = Pereirna | first6 = G. | last7 = Prada | first7 = F. | year = 2014 | title = Effects of six carbohydrates sources on diet digestibility and postprandial glucose and insulin responses in cats | url = | journal = Journal of Animal Science | volume = 86 | issue = | pages = 2237–2246 }}</ref> The degree of glucose peaks and the duration of the elevated glucose levels ultimately depends on the glycemic index of the carbohydrates used in the diet.<ref name=":73" /> Typically a diet of low protein is replaced with added carbohydrate content.<ref>Coradini M., Rand J., Morton J., Rawlings J. 2014. Metabolic determinants of body weight after cats were fed a low-carbohydrate high-protein diet or a high-carbohydrate low-protein diet ab libitum for 8 weeks. Domestic Animal Endocrinology. 49(2014): 70-79</ref> In some cases, fat can be added to lower protein diets in order to increase the energy density of the food product.<ref name=":103">{{Cite journal|last=Paßlack|first=Nadine|last2=Kohn|first2=Barbara|last3=Doherr|first3=Marcus G.|last4=Zentek|first4=Jürgen|date=2017-01-10|title=Impact of Dietary Protein Concentration and Quality on Immune Function of Cats|url=http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0169822|journal=PLOS ONE|volume=12|issue=1|pages=e0169822|doi=10.1371/journal.pone.0169822|issn=1932-6203}}</ref> A nutritional balance of amino acids is important in low protein cat diets as cats are highly sensitive to deficiencies in arginine, taurine, methionine, and cysteine.<ref name=":42" /> Therefore, supplementation of these essential amino acids is important and commonly found in cat foods.<ref>Knight A., Leitsberger M. 2016. Vegetarian versus meat-based diets for companion animals. Animals Journal. 6(57): 1-20</ref> The supplementation of polyunsaturated omega-3 fatty acids is common in products with lower protein as it plays a positive role in protecting the kidneys which is an issue for many cats on a low protein diet.<ref name=":15">{{Cite journal|last=Cline|first=Martha|date=March 2016|title=Nutritional Management of Chronic Kidney Disease in Cats and Dogs|url=http://todaysveterinarypractice.navc.com/wp-content/uploads/2016/05/2016-0304_ACVN-Nutrition.pdf|journal=Today's Veterinary Practice|volume=|pages=58–66|via=}}</ref> Similarly, mineral composition is important and low protein diets result in a low phosphorus content that benefits the renal care and prevention of kidney disease.<ref name=":42" /><ref name=":142"/> ==== Benefits to low protein diets ==== Feeding a lower protein content can help lower the amount of calcium being excreted in the feces and urine.<ref name=":82">{{Cite journal|last=PaBlack, N., Burmeier, H., Brenten, T., Neumann, K.|first=Zentek, J.|date=2014|title=Relevance of dietary protein concentration and quality as risk factorsfor the formation of calcium oxalate stones in cats|url=|journal=Journal of Nutritional Science|volume=3 | issue = 51 |pages=1–10|via=}}</ref> It has been observed that urinary calcium concentrations and fecal calcium excretion is related to increasing protein concentration in the diet.<ref name=":82" /> Increasing calcium in the urine and feces can indicate increased calcium mobilization (for example of bone) within a cat instead of increased intestinal calcium absorption.<ref name=":82" /> Lower protein fed to cats can also decrease renal oxalate excretion, and therefore, decrease renal oxalate and calcium concentrations to support the decrease in urinary calcium concentrations, which contributes to the decrease in urinary relative saturations with calcium oxalate and can decrease the probability of a cat developing calcium oxalate stones.<ref name=":82" /> A lower amount of harmful bacteria is accumulated with a lower protein diet which helps to increase the amount of positive bacteria present in the gut.<ref>{{Cite journal|last=Pinna|first=C|last2=Stefanelli|first2=C|last3=Biagi|first3=G|date=December 2014|title=In vitro effect of dietary protein level and nondigestible oligosaccharides on feline fecal microbiotal|url=|journal=Journal of Animal Science|volume=92|issue=12|pages=5593–5602|doi=10.2527/jas2013-7459|via=}}</ref> ==== Consequences of low protein diets ==== In low protein diets, unless the protein source is a high quality protein such as an animal-based protein, cats (and especially kittens) have been shown to develop [[retina]]l degeneration due to a deficiency in [[taurine]], an essential amino acid for cats that is derived from animal protein.<ref>{{cite journal | last1 = Hayes | first1 = K.C. | last2 = Carey | first2 = R.E. | last3 = Schmidt | first3 = S.Y. | year = 1975 | title = Retinal Degeneration Associated with Taurine Deficiency in the Cat | url = | journal = Science | volume = 188 | issue = 4191| pages = 949–951 | doi=10.1126/science.1138364}}</ref> Since cats have such a high protein requirement, lower protein content, and thus lower amino acid concentrations, in the diet has been linked to health defects such as lack of growth, decreased food intake, muscle atrophy, hypoalbuminemia, skin alterations, and more.<ref name=":22">{{Cite journal|last=Villaverde, C.|first=Fascetti, A.J.|date=2014|title=Macronutrients in Feline Health|url=|journal=The Veterinary clinics of North America Small Animal Practice|volume=44|pages=699–717|via=|doi=10.1016/j.cvsm.2014.03.007}}</ref> Cats on lower protein diets are more likely to lose weight, and to lose lean body mass.<ref name=":22" /> Low protein diets that are high in carbohydrates have been found to decrease glucose tolerance in cats.<ref name=":17">{{cite journal | last1 = Eisert | first1 = R | year = 2011 | title = Hypercarnivory and the brain: protein requirements of cats reconsidered | url = | journal = Journal of Comparative Physiology | volume = 181 | issue = | pages = 1–17 | doi=10.1007/s00360-010-0528-0}}</ref> With a decreased glucose tolerance, clinical observations have confirmed that cats consuming large proportions of metabolizable energy, in the form of carbohydrates rather than protein, are more likely to develop [[hyperglycemia]], [[hyperinsulinemia]], [[insulin resistance]], and [[obesity]].<ref name=":17" /> Cats have a high priority for [[gluconeogenesis]] to provide energy for tissues like the brain.<ref name=":17" /> The rate at which it{{clarify|date=December 2017}} operates does not change despite having a low protein diet.<ref name=":92">{{Cite journal|last=Silva, S.V.P.S.|first=Mercer, J.R.|date=1985|title=Effect of Protein Intake on Amino Acid Catabolism and Gluconeogenesis by Isolated Hepatocytes from the Cat (Felis Domestica|url=|journal=Comparative biochemistry and physiology|volume=80 | issue = 3 |pages=603–607|via=|doi=10.1016/0305-0491(85)90298-6}}</ref> Despite now being able to down-regulate{{clarify|date=December 2017}} gluconeogenesis, cats are able to regulate their amino acid [[catabolism]] in response to a low protein diet, probably by increasing the synthesis of enzyme proteins without altering the catalytic rate.<ref name=":92" /> This collectively can make a cat "wasteful" of amino acids supplied in a low protein diet.<ref name=":92" /> Low protein diets have been shown to lower the levels of [[:simple:Eosinophil granulocyte|eosinophilic granulocytes]] in cats, which impacts the overall function of the immune system.<ref name=":103"/> === Gastrointestinal health diets === The [[gastrointestinal tract]] is the source of [[nutrient]] absorption, making it integral to overall health.<ref name="book" /> Therefore, feeding your cat for optimal digestive health is key for a healthy cat. Research shows [[fiber]], [[prebiotics]], [[probiotics]], [[antioxidants]] and [[fatty acids]] are important in maintaining gastrointestinal health. ==== Fiber ==== The addition of [[fiber]] at optimal levels in a diet is essential for the normal function and health of the [[gastrointestinal tract]].<ref name="book">{{cite book|last1=Case|first1=Linda P.|last2=Hayek|first2=Michael G.|last3=Daristotle|first3=Leighann|last4=Raasch|first4=Melody Foess|title=Canin and Feline Nutrition: A Resource for Companion Animal Professionals|date=2011|publisher=Mosby Inc.|location=Maryland Heights, Missouri|edition=Third}}</ref>  Dietary fibers are plant [[carbohydrates]] which cannot be digested by mammalian [[enzymes]].<ref name="book" /> These structural plant carbohydrates include [[pectin]], [[lignin]], [[cellulose]], [[hemicellulose]], muclinage, and gums.<ref name="book" /> Different types of fibers have varying levels of [[solubility]] and [[fermentation]]; this ranges from pectin which is highly fermentable, to [[beet pulp]] which is moderately fermentable, to cellulose which is non-fermentable.<ref name="book" /> Non-fermentable fibers helps with satiety, maintenance of a normal intestinal transit time and gastrointestinal motility as well as increasing diet bulk.<ref name="book" /> Fermentable fibers, on the other hand, are fermented to [[short chain fatty acids]] by bacteria in the colon and have variable effects on [[gastric emptying]].<ref name="book" /> Moderately soluble fibers have been linked to increased colon weight as well as an increased mucosal surface area for absorption of nutrients.<ref name="book" />  Fiber, though it is not an essential nutrient, is important for a healthy gastrointestinal tract.<ref name="book" /> The microbes found in the cat’s large intestine have the ability to ferment dietary fibers to short chain fatty acids.<ref name="book" /> Cells of the gastrointestinal tract are constantly dying and being replaced by new cells, which requires a lot of energy.<ref name="book" /> The fatty acids produced are used as energy sources for these [[epithelial cells]] which line the gastrointestinal tract.<ref name="book" /> As a result of the presence of energy from the fatty acids, colonic [[cell proliferation]] is increases.<ref name="book" />  Short chain fatty acids production from dietary fibers have many other advantageous effects on the gastrointestinal tract.<ref name="book" /><ref name="vitro">{{cite journal|last1=Sunvold|first1=G. D.|last2=Hussein|first2=H. S.|last3=Fahey Jr.|first3=G. C.|last4=Merchen|first4=N. R.|last5=Reinhart|first5=G. A.|title=In Vitro Fermentation of Cellulose, Beet Pulp, Citrus Pulp, and Citrus Pectin Using Fecal Inoculum from Cats, Dogs, Horses, Humans, and Pigs and Ruminal Fluid from Cattle|journal=Journal of Animal Science|date=July 1995|volume=73|page=3639|doi=10.2527/1995.73123639x}}</ref> They increase motility by stimulating rhythmic contractions of the distal portion of the small intestine, which potentially decreases fermentation in the small intestine while increasing it in the large intestine for further fatty acid absorption.<ref name="book" /> Blood flow to the colon also increases with the presence of short chain fatty acids.<ref name="book" /> These fatty acids also increase sodium absorption which helps maintain normal [[electrolyte]] and [[fluid balance]] in the intestine, reducing the risk for diarrhea .<ref name="book" /> These [[homeostatic]] conditions of the intestinal tract promote the growth of beneficial bacteria while inhibiting the proliferation of pathogenic ones.<ref name="book" /> A healthy and balanced gut [[microbiome]] is important for maintaining a healthy digestive tract.<ref name="book" />  Fibers promote bacterial growth and activity in the large intestine.<ref name="book" /> It is essential for a healthy gastrointestinal tract to have a healthy and stable [[gut microbiota]].<ref name="meta">{{cite journal|last1=Barry|first1=Kathleen A.|last2=Middelbos|first2=Ingmar S.|last3=Boler|first3=Brittany M. Vester|last4=Dowd|first4=Scot E.|last5=Suchodolski|first5=Jan S.|last6=Henrissat|first6=Bernard|last7=Coutinho|first7=Pedro M.|last8=White|first8=Bryan A.|last9=Fahey Jr.|first9=George C.|last10=Swanson|first10=Kelly S.|title=Effects of Dietary Fiber on the Feline Gastrointestinal Metagenome|journal=Journal of Proteome Research|date=October 2012|volume=11|pages=5924–5933|doi=10.1021/pr3006809}}</ref> The [[microorganisms]] present in the colon are responsible for the fermentation of the fiber into short chain fatty acids and for the production of some [[vitamins]].<ref name="book" /><ref name="disease">{{cite journal|last1=Zoran|first1=Debra L.|title=Nutritional Management of Feline Gastrointestinal Diseases|journal=Topics in Companion Animal Medicine|date=November 2008|volume=23|issue=4|pages=200–204–205|doi=10.1053/j.tcam.2008.08.003}}</ref> ===== Prebiotics ===== [[Prebiotics]] are short-chain carbohydrates classified as fibers with an added aspect as they selectively promote the growth of beneficial bacteria.<ref name="book" /><ref name="FOS">{{cite journal|last1=Barry|first1=K. A.|last2=Wojcicki|first2=B. J.|last3=Middelbos|first3=I. S.|last4=Vester|first4=B. M.|last5=Swanson|first5=K. S.|last6=Fahey Jr.|first6=G. C.|title=Dietary cellulose, fructooligosaccharides, and pectin modify fecal protein catabolites and microbial populations in adult cats|journal=Journal of Animal Science|date=May 3, 2010|volume=88|pages=2978–2983|doi=10.2527/jas.2009-2464}}</ref><ref name="disease" /> By promoting the health and proliferation of beneficial bacteria, they suppress the growth of pathogenic ones by outcompeting them.<ref name="disease" /> [[Insulin]], [[galactooligosaccharides]], [[lactulose]], [[fructooligosaccharides]] (FOS) and mannanoligosaccharides (MOS) are all examples of prebiotics.<ref name="book" /> ==== Probiotics ==== Probiotics are becoming increasingly popular in the diets of felines.<ref name="[16]">{{cite journal|last1=Weese|first1=S|last2=Arroyo|first2=L|title=Bacteriological evaluation of dog and cat diets that claim to contain probiotics|journal=The Canadian Veterinary Journal|date=2003|volume=44|issue=3}}</ref> They are included in the diet to increase the number of bacteria and microbes that are normally present in a healthy gut.<ref name="[16]" /> Probiotics are considered a supplement rather than part of nutrition.<ref name="[16]" /> Therefore, there are no strict regulations to the amount of probiotics that should be included in foods.<ref name="[16]" /> The function of probiotics goes beyond basic nutrition and has many benefits to the health of the organism.<ref name="[16]" /> The use of probiotics can help in the prevention and treatment of certain diseases or disorders of felines.<ref name="[17]">{{cite journal|last1=Grześkowiak|first1=Lukasz|last2=Endo|first2=Akihito|last3=Shea|first3=Beasley|title=Microbiota and probiotics in canine and feline welfare|journal=Anaerobe|date=2015|volume=34|pages=14–23|doi=10.1016/j.anaerobe.2015.04.002}}</ref> Examples include prevention of allergies, diarrhea, symptoms relating to stress, etc.<ref name="[17]" /> The health of the cats is very much dependent on the fermentation that occurs through gut biota.<ref name="[17]" /> The gut biota has an important role in the metabolism, absorption, and protective functions of the gastro intestinal tract.<ref name="[17]" /> Felines have different gut bacteria than canines.<ref name="[17]" /> However, the most common biota that are found in both felines and canines are Firmicutes, Bacteroidetes, Proteobacteria, and Fusobacteria .<ref name="[17]" /> Although these are the most common types of gut biota found in felines, there are variances between independent cats.<ref name="[17]" /> Each cat has their own unique and independent number and type of gut microbes.<ref name="[17]" /> ==== Antioxidants ==== {{Main article|Antioxidant}} [[Nutraceuticals]] such as [[antioxidants]] are considered to be additives of gastrointestinal diets to prevent digestive upset.<ref name="book" /> Antioxidants have the ability to remove free radicals from the body which can cause damage to cell membranes, and are involved in chronic degenerative diseases.<ref name="[7]">{{cite journal|last1=Bauer|first1=J.|title=Evaluation of nutraceuticals, dietary supplements, and functional food ingredients for companion animals.|journal=Journal of the American Veterinary Medical Association|date=June 2001|volume=218|issue=11|pages=1755–1760|doi=10.2460/javma.2001.218.1755}}</ref> [[Free radicals]] amplify inflammation by causing release of pro-inflammatory [[cytokines]].<ref name="[6]">{{cite journal|last1=Conner|first1=E.M.|last2=Grisham|first2=M.B.|title=Inflammation, free radicals and antioxidants.|journal=Journal of Nutrition|date=February 1996|volume=12|issue=4|pages=274–277|doi=10.1016/s0899-9007(96)00000-8}}</ref> Free radicals can be caused by many factors such as stress, disease and age.<ref name="[7]" /> Some oxygen-derived free radicals can produce ischemia in the small bowel and stomach of cats.<ref name="[8]">{{cite journal|last1=Perry|first1=M.|last2=Wadhwa|first2=S.|last3=Parks|first3=D.A.|last4=Pickard|first4=W.|last5=Granger|first5=D.N.|title=Role of oxygen radicals in ischemia-induced lesions in the cat stomach.|journal=American Gastroenterological Association|date=1986|volume=90|pages=362–367|doi=10.1016/0016-5085(86)90933-9}}</ref> Combinations of antioxidants have been reported to improve serum vitamin status, suppress [[lipid peroxidation]] and distributes the effects of exercise on the immune system.<ref name="[9]">{{cite journal|last1=Bontempo|first1=V.|title=Nutrition and health of dogs and cats: evolution of pet food.|journal=Veterinary Research Communications|date=2005|volume=29|pages=45–50|doi=10.1007/s11259-005-0010-8}}</ref> The most common antioxidants found in cat gastrointestinal diets are vitamin E and vitamin C. ===== Vitamin E ===== {{Main article|Vitamin E}} The addition of Vitamin E as an antioxidant in gastrointestinal health cat food diets can have a positive effect of improving the animal’s immune function and prevent against infections.<ref name="[10]">{{cite journal|last1=Puertollano|first1=M.A.|last2=Puertollano|first2=E.|last3=Alvarez de Cienfuegos|first3=G.|last4=de Pablo|first4=M.A.|title=Dietary antioxidants: immunity and host defense.|journal=Current Topics in Medical Chemistry|date=2011|volume=11|issue=14|pages=175–176}}</ref> Vitamin E is a free radical scavenger that functions as a chain-breaking antioxidant to prevent free radical damage of cell membranes.<ref name="[6]" /><ref name="[11]">{{cite journal|last1=Jewell|first1=D.E.|last2=Toll|first2=P.W.|last3=Wedekind|first3=K.J.|last4=Zicker|first4=S.C.|title=Effect of increasing dietary antioxidants on concentrations of vitamin E and total alkenals in serum of dogs and cats.|journal=Veterinary Therapeutics|date=2000|volume=1|issue=4|pages=264–272}}</ref> Vitamin E aids in protecting cells from highly reactive oxygen species within the lungs, muscles, skin, brain, tissues and red blood cells.<ref name="[7]" /> Supplementation of vitamin E in the diet benefits the immune system and improves resistance to infections and diseases.<ref name="[7]" />  The [[National Research Council (United States)|National Research Council]] (NRC) suggested a ratio of vitamin E to polyunsaturated fatty acids be 0.6:1 to ensure enough vitamin E to combat any free radicals.<ref name="[9]" /> [[Polyunsaturated fatty acids]] (PUFA) are prone to oxidative destruction in cellular membranes and increases the requirement for antioxidants.<ref name="[7]" /> ===== Vitamin C ===== {{Main article|Vitamin C}} Vitamin C (ascorbic acid) is a water-soluble antioxidant and a free radical scavenger where it will donate an [[electron]] to compounds with unpaired elections or reactive but not radical compounds.<ref name="[6]" /><ref name="[12]">{{cite journal|last1=Padayatty|first1=S.J.|last2=Katz|first2=A.|last3=Wang|first3=Y.|last4=Eck|first4=P.|last5=Kwon|first5=O.|last6=Lee|first6=J.H.|last7=Chen|first7=S.|last8=Corpe|first8=C.|last9=Dutta|first9=A.|last10=Dutta|first10=S.K.|last11=Levine|first11=M.|title=Vitamin C as an antioxidant: evaluation of its role in disease prevention.|journal=Journal of the American College of Nutrition|date=2003|volume=22|issue=1|pages=18–35|doi=10.1080/07315724.2003.10719272}}</ref> Supplements of Vitamin C reduced oxidative DNA damage in cats prone to renal insufficiency, and can be beneficial to add into diets for cats suffering from [[renal diseases]].<ref name="[13]">{{cite journal|last1=Yu|first1=S.|last2=Paetau-Robinson|first2=I.|title=Dietary supplementation of vitamin E and C and beta-carotene reduce oxidative stress in cats with renal insufficiency.|journal=Veterinary Research Communications|date=2006|volume=30|pages=403–413|doi=10.1007/s11259-006-3269-5}}</ref> Vitamin C is not essential for cats as it is not required by the Association of American Feed Control Officials (AAFCO), however is commonly added into pet foods as an antioxidant.<ref name="[13]" /> Ascorbic acid is known to not only be an antioxidant, but also to function in [[gene expression]], as a co-substrate, and have unique biosynthetic pathways in different organisms.<ref name="[14]">{{cite journal|last1=Arrigoni|first1=O.|last2=De Tullio|first2=M.C.|title=Ascorbic acid: much more than just an antioxidant.|journal=Biochimica et Biophysica Acta|date=2002|volume=1569|pages=1–9|doi=10.1016/s0304-4165(01)00235-5}}</ref> ==== Fatty Acids ==== A fat is a type of lipid which comes in the form of many different molecules throughout the body, and fatty acids are just one type of fat that can be found.<ref name="book" /> Fatty acids come in a variety of molecular shapes, sizes and chemical compositions.<ref name="book" /> They can also be divided into many different categories.<ref name="book" /> Fatty acids can become attached to different molecules like carbohydrates or proteins and can elicit a wide range of functions in the body.<ref name="book" /> Some of those functions include: providing long-term energy storage, insulation (prevents heat loss, protects vital organs, helps transmit nerve impulses faster), structure, transportation around the body for nutrients and other biological molecules, and can also be precursors to other compounds in the body such as hormones (some of which are important for gut/immune/overall health).<ref name="book" /> The length, degree of saturation and configuration of a fatty acid affects how it is broken down, absorbed and utilized in the gastrointestinal tract (GIT).<ref name="book" /> ===== Inflammation ===== Inflammation is the process by which the body begins to heal and defend itself from viral and bacterial infections and physical damage like burns or cuts.<ref name="[28]">{{cite journal|last1=Calder|first1=P.C.|last2=Albers|first2=R.|last3=Antoine|first3=J.M.|last4=Blum|first4=S.|last5=Bourdet-Sicard|first5=R.|last6=Ferns|first6=G.A.|last7=Folkerts|first7=G.|last8=Friedmann|first8=P.S.|last9=Frost|first9=G.S.|last10=Guarner|first10=F.|last11=Lovik|first11=M.|last12=Macfarlane|first12=S.|last13=Meyer|first13=P.D.|last14=M'Rabet|first14=L.|last15=Serafini|first15=M.|last16=van Eden|first16=W.|last17=van Loo|first17=J.|last18=Vas Dias|first18=W.|last19=Vidry|first19=S.|last20=Winklhofer-Roob|first20=B.M.|last21=Zhao|first21=J.|title=Inflammatory Disease Processes and Interactions with Nutrition|journal=British Journal of Nutrition|date=May 2009|volume=101|pages=1, 14|accessdate=23 November 2017|doi=10.1017/s0007114509377867}}</ref> Typical signs of inflammation are: redness, swelling, heat, pain and loss of function in the affected area.<ref name="[28]"/> The inflammatory response is a normal response for the body to make when injured but if the response gets out of control or becomes excessive, it can cause damage in the host with a wide range of effects from mild allergies to severe GIT diseases.<ref name="[28]"/> Inflammation is then an important response to focus on because it is very involved in the host’s defense mechanisms and is often involved in GIT diseases.<ref name="[28]"/> The inflammatory process begins with intracellular and intercellular communication around the body using chemical mediators like chemokines and cytokines, which left unregulated can get out of control and cause excessive inflammation.<ref name="[28]"/> Anti-inflammatories and the ratio of omega-6 to omega-3 fatty acids can influence the initiation and severity of the inflammatory response, controlling factors like intracellular signaling cascades and receptors for inflammatory molecules.<ref name="[28]"/> Fat (adipose tissue) is also an important and potent mediator in the inflammatory process and therefore regulation of fat stores is important in keeping the inflammatory response in the body under control.<ref name="[28]"/> ===== Nutrition and GIT in Cats ===== To achieve optimal cellular health (especially in the gut) and to maintain a healthy microbiome, proper nutrition is necessary (nutrition is multifactorial an complex).<ref name="[29]">{{cite journal|last1=Zoran|first1=Debra L.|title=Nutritional Management of Feline Gastrointestinal Diseases|journal=Topics in Companion Animal Nutrition|date=2008|volume=23|issue=4|pages=200–203|doi=10.1053/j.tcam.2008.08.003}}</ref> Cats with GI diseases must consume an easily digestible diet with the appropriate nutrients provided by easily digestible ingredients and in the correct ratio which is recommended to be fed in small portions frequently throughout the day, so as o not overwhelm the digestive system.<ref name="[29]"/> It is also important for fat to be digestible because too much undigested fat that reaches the end of the digestive tract (colon) has the possibility of being fermented and can worsen the symptoms of GIT disease and induce other reactions like diarrhea.<ref name="[29]"/> It has also been suggested that cats should eat diets tailored to the section of the GIT that is diseases.<ref name="[29]"/> When certain nutrients like fructooligosaccharides (FOS) are included in the diet, the microbiome and fatty acid content are often changed for the better.<ref name="book" /> An example would be less branched-chain fatty acids (BCFAs; which are more difficult and take more time to digest) are produced and more short-chain fatty acids (SCFAs; which are easier to digest and are more readily available sources of energy which can be used for supporting cell turnover keeping cells, like those found in the GIT, healthier thereby improving GIT health and immune function) are produced.<ref name="book" /> FOS can also impact production of other fatty acids.<ref name="book" /> ===== Fat Digestion ===== Cats have a higher tolerance for a greater amount of fat in the diet, and although its digestion is complex and important (pertaining to its many functions and its influence on immune and inflammatory responses), fat composition in the diet appears to have a small effect on GI disease in cats.<ref name="[29]"/> Taurine is an essential sulphur-containing amino acid for cats and some other mammals with many unique essential functions, one of which is the conjugation of bile acids which are important in the metabolism of fatty acids.<ref name="book" /> Fat levels are important so that the animal wants to eat the diet.<ref name="[29]"/> So, although high levels of fat may be detrimental, too low a fat level in the diet and the animal will not eat it.<ref name="[29]"/> Low levels may be only beneficial if the GI disease involves maldigestion, malabsorption and/or influences the population of bacteria in the gut too much.<ref name="[29]"/> ===== Fatty Acids and Gastrointestinal Health in Cats ===== One group of fatty acids that is particularly important for gastrointestinal (GI) health is the essential fatty acid (EFA) group.<ref name="book" /> All EFAs are polyunsaturated (they have more than one double bond in their fatty acid chain).<ref name="book" /> EFAs are important to have in the diet in adequate amounts, especially for the cat, as since they are essential (meaning the body produces little to none so it must be included in the diet) and cats have very low activity or simply lack the digestive enzymes to generate the EFAs that are important in mediating the inflammatory response.<ref name="book" /> EFAs also vary in size, have many different functions and can also be further divided into other categories, two of which are very important for GI health: the omega-6 and omega-3 fatty acids (the omega in the name denotes the position of the first double bond in a fatty acid counting from the methyl end).<ref name="book" /> These fatty acids are most effective when present in adequate and appropriate balanced ratios dependent upon stage of life and production of the animal.<ref name="book" /> One very important function of EFAs is the production of eicosanoids (molecules that are important in immune and inflammatory regulation).<ref name="book" /> Eicosanoids are like hormones and act in a local fashion with short lives.<ref name="book" /> Different EFAs have different effects on the inflammatory response.<ref name="book" /> Omega-6 fatty acids at high levels can suppress the functions of the immune system (large part of which is located in the GIT) and promote inflammation, platelet aggregation and hypersensitive reactions like allergies.<ref name="book" /> Omega-3 fatty acids act in the opposite direction of omega-6 fatty acids by: promoting anti-inflammation and depressing aggregation and immunosuppression.<ref name="book" /> Ratio of omega-6 to omega-3 fatty acids can be changed using diet, optimal ratio of omega-6 to omega-3 fatty acids is considered to be within the range of 5:1 to 10:1.<ref name="book" /> The right ratio (different for everyone as everyone is unique) helps reduce inflammation and mediate immune responses as both omega fatty acids utilize the same enzymes in their metabolic journey.<ref name="book" /> Some sources of omega-6 fatty acids include: corn oil, sunflower oil and soybean oil.<ref name="book" /> Some sources of omega-3 fatty acids include: cold-water fish oil, flaxseed, canola oil and soybean oil.<ref name="book" /> ===== Areas for Improvement ===== There is very little research on cats in general, especially when diving into very targeted topics like GIT health of cats and the effects of fatty acids of any length on their digestive system, especially cats with GIT disorders.<ref name="book" /> GIT diseases are common in cats and it has been suggested that in the case of long-term GI diseases, diet is extremely important in modulation and manipulating the effects.<ref name="[29]"/> Levels of fat included in the diet should be studied more and monitored as not only does adipose tissue play a role in the inflammatory process, but it is also used as a palatant to make food more appealing.<ref name="book" /> As fat is high in energy, overeating (which can cause an animal to become overweight or obese) is not uncommon in foods with high levels of fat as fats are very palatable.<ref name="book" /> Although not well studied, evidence from previous studies completed in animals and humans (who have similar digestive tracts to cats) suggest a proper ratio and use of omega-6 to omega-3 fatty acids will help mediate inflammatory diseases, especially ones present in the GIT.<ref name="book" /> ===Homemade food=== {{Further|Raw feeding}} Many pet owners feed cats homemade diets. These diets generally consist of some form of cooked or [[Raw feeding|raw]] meat, bone, vegetables, and supplements, such as [[taurine]] and [[Multivitamin]]<nowiki/>s.<ref name=":8" /> Homemade diets either follow a recipe, such as the BARF diet which provides a series of options for the pet owner to make, or rely on the constant rotation of ingredients to meet nutrient requirements.<ref name=":8" /> A study was conducted that analyzed 95 homemade BARF diets and found that 60% of these were nutritionally imbalanced in either one or a combination of calcium, phosphorus, vitamin D, iodine, zinc, copper, or vitamin A content.<ref>{{Cite journal|last=Dillitzer|first=Natalie|last2=Becker|first2=Nicola|last3=Kienzle|first3=Ellen|date=October 2011|title=Intake of minerals, trace elements and vitamins in bone and raw food rations in adult dogs|url=https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/div-classtitleintake-of-minerals-trace-elements-and-vitamins-in-bone-and-raw-food-rations-in-adult-dogsdiv/7520574DA173F4DB29330A6F858DE0E0|journal=British Journal of Nutrition|volume=106|issue=S1|pages=S53–S56|doi=10.1017/S0007114511002765|issn=1475-2662}}</ref> ===Bisphenol A=== A 2004 study reported that food packaged in cans coated with [[bisphenol A]] is correlated with the development of [[hyperthyroidism]] in cats.<ref> {{cite journal | last = Edinboro| first = Charlotte H.| author2 = Scott-Moncrieff, Catharine |author3=Janovitz, Evan |author4=Thacker, Leon |author5=Glickman, Larry T.|date=March 2004| title = Epidemiologic study of relationships between consumption of commercial canned food and risk of hyperthyroidism in cats| journal = [[Journal of the American Veterinary Medical Association]]| volume = 224| issue = 6| pages = 879–86 | doi = 10.2460/javma.2004.224.879 | url = http://avmajournals.avma.org/doi/abs/10.2460/javma.2004.224.879 | accessdate = 2008-03-10 }}</ref> ===Food allergy=== {{Main|Allergies in cats}} Food allergy is a non-seasonal disease with skin and/or gastrointestinal disorders. The main complaint is excessive scratching ([[pruritus]]) which is usually resistant to treatment by [[Glucocorticoid|steroidal]] [[anti-inflammatory]] [[medication|drugs]]. The exact prevalence of food allergy in cats remains unknown. In 20 to 30% of the cases, cats have concurrent allergic diseases ([[atopy]]/flea-allergic [[dermatitis]]). A reliable diagnosis can only be made with [[Elimination diet|dietary elimination-challenge trials]]. [[Food allergy|Allergy]] [[Allergy testing|testing]] is necessary for the identification of the causative food component(s). Therapy consists of avoiding the offending food component(s).<ref>{{cite journal |vauthors=Verlinden A, Hesta M, Millet S, Janssens GP |title=Food allergy in dogs and cats: a review |journal=Crit Rev Food Sci Nutr |volume=46 |issue=3 |pages=259–73 |year=2006 |pmid=16527756 |doi=10.1080/10408390591001117 }}</ref> ===Malnutrition=== Malnutrition can be a problem for cats fed non-conventional diets. Cats fed exclusively on raw, [[freshwater fish]] can develop a [[thiamine]] deficiency. Those fed exclusively on liver may develop [[vitamin A]] toxicity. Also, exclusively meat-based diets may contain excessive [[protein]] and [[phosphorus]] whilst being deficient in [[calcium]], [[vitamin E]], and [[microminerals]] such as [[copper]], [[zinc]], and [[potassium]]. [[Energy density]] must also be maintained relative to the other [[nutrients]]. When [[vegetable oil]] is used to maintain the energy balance cats may not find the food as [[palatable]].<ref>{{cite web | url = http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/182902.htm | title = Nutritional Requirements and Related Diseases | accessdate = 2006-10-27 | author = John E. Bauer, [[D.V.M.]], [[Ph.D.]], [[Dipl. A.C.V.N.]] | date = 2005-01-01 | work = [[Merck Veterinary Manual]] | isbn= 0-911910-50-6 | edition=9th | publisher = [[Merck & Co., Inc.]] }}</ref> ===Recalls=== {{Main article|2007 pet food recalls}} The broad [[Product recall|pet food recalls]] starting in March 2007 came in response to reports of [[renal failure]] in pets consuming mostly wet pet foods made with [[Gluten|wheat gluten]] from a single [[People's Republic of China|Chinese]] company beginning in February 2007. Overall, several major companies recalled more than 100 brands of pet foods with most of the recalled product coming from Menu Foods. The most likely cause according to the FDA is the presence of [[melamine]] in the wheat gluten of the affected foods. Melamine is known to falsely inflate the protein content rating of substances in laboratory tests. The economic impact on the pet food market has been extensive, with Menu Foods alone losing roughly [[United States Dollar|$]]30 million from the recall. Some companies were not affected and utilized the situation to generate sales for alternative pet foods.<ref>{{Cite web|url = http://www.newsweek.com/capitalizing-pet-food-panic-101439|title = CAPITALIZING ON PET-FOOD PANIC|date = |access-date = |website = |publisher = }}</ref> ==Environmental impact== {{further|Overfishing}} {{See also|Environmental effects of meat production}} In a study on the impacts of the pet food industry on world fish and seafood supplies, researchers estimate that 2.48 million metric tonnes of fish are used by the cat food industry each year.<ref>{{cite journal |vauthors=De Silva SS, Turchini GM |title=Towards Understanding the Impacts of the Pet Food Industry on World Fish and Seafood Supplies |journal=Journal of Agricultural and Environmental Ethics |volume=21 |issue=5 |pages=459–67 |date=October 2008 |doi=10.1007/s10806-008-9109-6 |url=http://springerlink.com/content/30h281g68648h431/ |archive-url=https://archive.is/20130630091247/http://springerlink.com/content/30h281g68648h431/ |dead-url=yes |archive-date=2013-06-30 }}</ref><ref>[http://www.petfoodindustry.com/ViewNews.aspx?id=22588 Cats taking a bite out of world fish supply] {{webarchive|url=https://web.archive.org/web/20090114120956/http://www.petfoodindustry.com/ViewNews.aspx?id=22588 |date=2009-01-14 }} Petfood Industry News</ref> It was suggested that there needs to be "a more objective and pragmatic approach to the use of a limited and decreasing biological resource, for human benefit." [[Marine conservation]] activist [[Paul Watson]] argues that the reduction in [[forage fish]] such as those commonly used in cat food (sardines, herring, anchovy etc.) negatively affects fish higher up the food chain like cod, tuna and swordfish, not to mention marine mammals and birds.<ref>[http://www.seashepherd.org/news-and-media/editorial-080828-1.html Aqua Cats Are Eating the Oceans] Paul Watson, Sea Shepherd Conservation Society</ref> Based on 2004 numbers, cats in the US consume the caloric equivalent of what 192,000 ([[Demographics of the United States#Vital statistics|0.0655187%]]) Americans consume. While pet food is made predominantly using byproducts from human food productions, the increase in popularity of human-grade and byproduct-free pet food means there is increasing pressure on the overall meat supply.<ref>Pets and the Planet: A Practical Guide to Sustainable Pet Care. Carol Frischmann. (2009) Wiley Publishing, Inc.</ref> === Protein === AAFCO recommends 26% crude protein for feline diets on a dry matter basis,<ref name=":05"/> however dry cat food from the top 3 cat food brands in Canada of 2010<ref>{{Cite web|url=http://www.agr.gc.ca/resources/prod/Internet-Internet/MISB-DGSIM/ATS-SEA/PDF/6245-eng.pdf|title=Consumer Trends: Pet Food in Canada|last=|first=|date=2012|website=Agriculture and Agri-Food Canada|archive-url=|archive-date=|dead-url=|access-date=}}</ref> contained 34%, 40%, and 36% protein respectively, on a dry matter basis.<ref>{{Cite web|url=https://www.friskies.com/products/dry-cat-food/seafood-sensations/|title=Seafood Dry Cat Food {{!}} Seafood Sensations® {{!}} Friskies®|website=Friskies|language=en|access-date=2017-11-24}}</ref><ref>{{Cite news|url=https://www.whiskas.ca/en/our-products/dry-food/whiskas-meaty-selections-with-chicken|title=WHISKAS&#174; MEATY SELECTIONS&#174; with Chicken {{!}} WHISKAS&#174;|access-date=2017-11-24}}</ref><ref>{{Cite web|url=https://www.catchow.com/products/complete-formula/|title=Complete Formula Cat Food {{!}} Purina® Cat Chow®|website=www.catchow.com|language=en|access-date=2017-11-24}}</ref> High animal protein in cat food has increased in popularity due to consumer demand for natural diets, in which protein content is usually much higher than the AAFCO minimum levels.<ref name=":34"/> The effects of these trends results in a higher need for animal protein, which may have detrimental effects on sustainability.<ref>{{Cite journal|last=Reijnders|first=Lucas|last2=Soret|first2=Sam|date=2003-09-01|title=Quantification of the environmental impact of different dietary protein choices|url=http://ajcn.nutrition.org/content/78/3/664S|journal=The American Journal of Clinical Nutrition|language=en|volume=78|issue=3|pages=664S–668S|issn=0002-9165|pmid=12936964|doi=10.1093/ajcn/78.3.664s}}</ref> 6.4% of the USA's greenhouse gas emission is estimated to come from agriculture, and over 50% of the agricultural greenhouse gas emission comes from livestock.<ref name=":11">{{Cite journal|last=Swanson|first=Kelly S.|last2=Carter|first2=Rebecca A.|last3=Yount|first3=Tracy P.|last4=Aretz|first4=Jan|last5=Buff|first5=Preston R.|date=2013-03-01|title=Nutritional Sustainability of Pet Foods|url=http://advances.nutrition.org/content/4/2/141|journal=Advances in Nutrition: An International Review Journal|language=en|volume=4|issue=2|pages=141–150|doi=10.3945/an.112.003335|issn=2156-5376|pmid=23493530|pmc=3649094}}</ref> The large amount of livestock and fish protein used in pet food diets has been shown to have a much larger impact on the environment when compared to vegetable protein.<ref name=":11" /> Following only human trends, by 2050 approximately 1 billion hectares of land will need to be used for agriculture to sustain the human population.<ref name=":12">{{Cite journal|last=Okin|first=Gregory S.|date=2017-08-02|title=Environmental impacts of food consumption by dogs and cats|url=http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0181301|journal=PLOS ONE|volume=12|issue=8|pages=e0181301|doi=10.1371/journal.pone.0181301|issn=1932-6203}}</ref> In 2015, an estimated 77.8 million dogs and 85.6 millions cats were living in the USA.<ref name=":12" /> The consumer desire to feed their pets premium foods which advertise healthy and human-grade ingredients coupled with the increasing prevalence of pet ownership is causing increased pressure on the meat industry which could result in increased land usage for raising livestock to meet the growing demand.<ref name=":12" /><ref>{{Cite journal|last=Kumcu|first=Aylin|last2=Woolverton|first2=Andrea E.|title=Feeding Fido: Changing Consumer Food Preferences Bring Pets to the Table|url=http://www.tandfonline.com/doi/full/10.1080/10454446.2012.715575?scroll=top&needAccess=true|journal=Journal of Food Products Marketing|language=en|volume=21|issue=2|pages=213–230|doi=10.1080/10454446.2012.715575|year=2014}}</ref> In a study conducted by Okin in 2017, he suggests that if a quarter of all animal protein used in the food of American pets was human-grade, it would be equivalent to the energy needs of 5 million Americans.<ref name=":12" /> Okin uses an estimate of 33% of an animal's energy needs is derived from animal products; however, this is conservative in that many diets now have more than 33% of their diet in animal protein alone.<ref name=":12" /> Lowering protein levels in feline diets may help to improve the sustainability of both the human and pet food system by decreasing pressure on livestock agriculture and ultimately improving environmental effects.<ref name=":11" /> ==Nutrient chart== {| class="wikitable" style="text-align: center; width: 100%; font-size:85%;" |+ {{anchor|CFNP}} [[Association of American Feed Control Officials]] (AAFCO) Cat Food Nutrient Profiles&nbsp;{{efn|name=a}}&nbsp;<ref name="CFNPNP">{{cite web|author=David A. Dzanis, [[D.V.M.]], [[Ph.D.]], [[DACVN]] [[Division of Animal Feeds]], [[Center for Veterinary Medicine]] |date=November 1997 |url=http://www.fda.gov/cvm/petfood.htm |accessdate=2005-01-20 |title=SELECTING NUTRITIOUS PET FOODS |work=INFORMATION FOR CONSUMERS |publisher=[[Food and Drug Administration]] - [[Center for Veterinary Medicine]] |deadurl=yes |archiveurl=https://web.archive.org/web/20060625233223/http://www.fda.gov/cvm/petfood.htm |archivedate=June 25, 2006 }}</ref> <br />with Role of Vitamins & Minerals&nbsp;<ref name="CFNPFD" /> |- ! [[Nutrient]] !! Units<br>(Dry Matter Basis) !! Growth and<br>reproduction<br>minimum !! Adult<br>maintenance<br>minimum !! Maximum !! Functions !! Signs of deficiency/Excess |- | style="text-align:left" | [[Protein]] || [[%]] || 30.0 || 26.0 || || || |- | [[Arginine]] || [[%]] || 1.25 || 1.04 || || || * Deficiency ** [[Hyperammonemia]]  ** Symptoms include [[lethargy]], vomiting, [[ataxia]], [[hyperesthesia]] and can be serious enough to induce death and [[coma]]<ref name=":0">Bauer, J. (1998). Nutritional Uniqueness of Cats. ''Veterinary Quarterly,20''(Sup1), 78-79.</ref> |- | [[Histidine]] || [[%]] || 0.31 || 0.31 || || || |- | [[Isoleucine]] || [[%]] || 0.52 || 0.52 || || || |- | [[Leucine]] || [[%]] || 1.25 || 1.25 || || || |- | [[Lysine]] || [[%]] || 1.20 || 0.83 || || || |- | [[Methionine]] + [[cystine]] || [[%]] || 1.10 || 1.10 || || || |- | [[Methionine]] || [[%]] || 0.62 || 0.62 || 1.50 || || |- | [[Phenylalanine]] + [[tyrosine]] || [[%]] || 0.88 || 0.88 || || || |- | [[Phenylalanine]] || [[%]] || 0.42 || 0.42 || || || |- | [[Threonine]] || [[%]] || 0.73 || 0.73 || || || |- | [[Tryptophan]] || [[%]] || 0.25 || 0.16 || || || |- | [[Valine]] || [[%]] || 0.62 || 0.62 || || || |- | style="text-align:left" | [[Fat]] {{efn|name=b}} || [[%]] || 9.0 || 9.0 || || || |- | [[Linoleic acid]] || [[%]] || 0.5 || 0.5 || || || |- | [[Arachidonic acid]] || [[%]] || 0.02 || 0.02 || || * Liver health<ref name=":012">{{cite journal | last1 = Bauer | first1 = J.E. | year = 2006 | title = Metabolic basis for the essential nature of fatty acids and the unique dietary fatty acid requirements of cats | url = | journal = Journal of the American Veterinary Medical Association | volume = 229 | issue = 11| pages = 1729–1732 | doi=10.2460/javma.229.11.1729}}</ref> * Kidney health<ref name=":012" /> * Adrenal gland health<ref name=":012" /> * Skin health<ref name=":012" /> | * Deficiency ** Lack of inflammatory response<ref name=":72">Chamberlin, A., Mitsuhashi, Y., Bigley, K., & Bauer, J. (2011). Unexpected depletion of plasma arachidonate and total protein in cats fed a low arachidonic acid diet due to peroxidation. ''The British Journal of Nutrition,'' ''106''(S1), S131-4.</ref> ** Improper blood clotting<ref name=":72"/> ** Malfunction of reproductive and gastrointestinal systems<ref name=":4">Morris, J. (2004). Do cats need arachidonic acid in the diet for reproduction? ''Journal of Animal Physiology and Animal Nutrition,88''(3‐4), 131-137.</ref> ** Thickening of skin<ref name=":4" /> |- | style="text-align:left" colspan="7" | [[dietary minerals|Minerals]] |- | [[Calcium]] || [[%]] || 1.0 || 0.6 || || style="text-align: left;" | *Formation of bones and teeth *Blood coagulation *Nerve impulse transmission *Muscle contraction *Cell signaling | style="text-align: left;" | *Deficiency **Nutritional secondary hyperparathyroidism **loss of bone mineral content, which can lead to collapse and curvature of lumbar vertebrae and pelvic bones **bone pain, which can progress to pathological fractures *Excess **Depressed food intake **Decreased growth **Increased bone mineral density **Increased need for magnesium |- | [[Phosphorus]] || [[%]] || 0.8 || 0.5 || || style="text-align: left;" | *Skeletal structure *DNA and RNA structure *Energy metabolism *Locomotion *Acid-base balance | style="text-align: left;" | *Deficiency **Hemolytic anemia **Locomotor disturbances **Metabolic acidosis |- | [[Potassium]] || [[%]] || 0.6 || 0.6 || || style="text-align: left;" | *Acid-base balance *Nerve-impulse transmission *Enzymatic reactions *Transport functions | style="text-align: left;" | *Deficiency **Anorexia **Retarded growth **Neurological disorders, including ataxia and severe muscle weakness |- | [[Sodium]] || [[%]] || 0.2 || 0.2 || || style="text-align: left;" | *Acid-base balance *Regulation of osmotic pressure *Nerve impulse generation and transmission | style="text-align: left;" | *Deficiency **Anorexia **Impaired growth **Excessive thirst and drinking **Excessive urination |- | [[Chlorine]] / [[Chloride]] || [[%]] || 0.3 || 0.3 || || style="text-align: left;" | *Acid-base balance *Osmolarity of extracellular fluids | style="text-align: left;" | *Deficiency **Increased sodium concentration in renal fluid **Excess potassium excretion |- | [[Magnesium]]&nbsp;{{efn|name=c}} || [[%]] || 0.08 || 0.04 || || style="text-align: left;" | *Enzyme functions *Muscle and nerve-cell membrane stability *Hormone secretion and function *Mineral structure of bones and teeth | style="text-align: left;" | *Deficiency **Poor growth **Overextension of the carpal joints **Muscle twitching **Convulsions *Excess **Urinary tract stone formation in the presence of high pH |- | [[Iron]]&nbsp;{{efn|name=d}} || [[kg#SI multiples|mg]]/kg || 80.0 || 80.0 || || style="text-align: left;" | *Hemoglobin and myoglobin synthesis *Energy metabolism | style="text-align: left;" | *Deficiency **Poor growth **Pale mucous membranes **Lethargy **Weakness **Diarrhea *Excess **Vomiting and diarrhea |- | [[Copper]] (extruded food)&nbsp;{{efn|name=e}} || [[kg#SI multiples|mg]]/kg || 15.0 || 5.0 || || rowspan="2" style="text-align: left;" | *Connective tissue formation *Iron metabolism *Blood cell formation *Melanin pigment formation *Myelin formation *Defense against oxidative damage | rowspan="2" style="text-align: left;" | *Deficiency **Reduced weight gain **Longer time to conceive |- | [[Copper]] (canned food)&nbsp;{{efn|name=e}} || [[kg#SI multiples|mg]]/kg || 5.0 || 5.0 || |- | [[Manganese]] || [[kg#SI multiples|mg]]/kg || 7.5 || 7.5 || || style="text-align: left;" | *Enzyme functions *Bone development *Neurological function | style="text-align: left;" | No studies of deficiency in cats |- | [[Zinc]] || [[kg#SI multiples|mg]]/kg || 75.0 || 75.0 || 2000.0 || style="text-align: left;" | *Enzyme reactions *Cell replication *Protein and carbohydrate metabolism *Skin function *Wound healing | style="text-align: left;" | *Deficiency **Skin lesions **Growth retardation **Testicular damage |- | [[Iodine]] || [[kg#SI multiples|mg]]/kg || 0.35 || 0.35 || || style="text-align: left;" | *Thyroid hormone synthesis *Cell differentiation *Growth and development of puppies *Regulation of metabolic rate | style="text-align: left;" | *Deficiency **Enlargement of thyroid glands *Excess **Excessive tearing, salivation, and nasal discharge **Dandruff |- | [[Selenium]] || [[kg#SI multiples|mg]]/kg || 0.1 || 0.1 || || style="text-align: left;" | *Defense against oxidative damage *Immune response | style="text-align: left;" | No studies of deficiency in cats |- | style="text-align:left" colspan="7" | [[Vitamins]] |- | [[Vitamin A]] || [[International units|IU]]/kg || 9000.0 || 5000.0 || 750000.0 || style="text-align: left;" | *Vision *Growth *Immune function *Fetal development *Cellular differentiation *Transmembrane protein transfer | style="text-align: left;" | *Deficiency **Conjunctivitis **Cataracts, retinal degeneration, and other eye problems **Weight loss **Muscle weakness **Reproductive and developmental disorders *Excess **Skeletal lesions in kittens, particularly outgrowths of the cervical vertebrae **Osteoporosis |- | [[Vitamin D]] || [[International units|IU]]/kg || 750.0 || 500.0 || 10000.0 || style="text-align: left;" | *Maintenance of mineral status *Skeletal structure *Muscle contraction *Blood clotting *Nerve conduction *Cell signaling *Phosphorus balance | style="text-align: left;" | *Deficiency **Rickets **Abnormalities in skeletal development **Progressive paralysis **Ataxia **Lack of grooming **Reduction in body weight and food intake *Excess **Anorexia **Vomiting **Lethargy **Calcification of soft tissues |- | [[Vitamin E]]&nbsp;{{efn|name=f}} || [[International units|IU]]/kg || 30.0 || 30.0 || || style="text-align: left;" | *Defense against oxidative damage via free radical scavenging | style="text-align: left;" | *Deficiency **Anorexia **Depression **Pain sensitivity in abdomen **Fat tissue pathology |- | [[Vitamin K]]&nbsp;{{efn|name=g}} || [[kg#SI multiples|mg]]/kg || 0.1 || 0.1 || || style="text-align: left;" | *Activation of clotting factors, bone proteins, and other proteins | style="text-align: left;" | *Deficiency **Prolonged blood clotting times **Hemorrhaging |- | [[Vitamin B1]] / [[Thiamine]]&nbsp;{{efn|name=h}} || [[kg#SI multiples|mg]]/kg || 5.0 || 5.0 || || style="text-align: left;" | *Energy and carbohydrate metabolism *Activation of ion channels in neural tissue | style="text-align: left;" | *Deficiency **Neurological impairments including altered reflexes and convulsive seizures **Heart-rate disorders **Pathological changes in the central nervous system **Severe learning deficits |- | [[Riboflavin]] || [[kg#SI multiples|mg]]/kg || 4.0 || 4.0 || || style="text-align: left;" | *Enzyme functions | style="text-align: left;" | *Deficiency **Cataracts **Fatty livers **Testicular atrophy |- | [[Pantothenic acid]] || [[kg#SI multiples|mg]]/kg || 5.0 || 5.0 || || style="text-align: left;" | *Energy metabolism | style="text-align: left;" | *Deficiency **Stunted growth **Fatty changes in liver **Small bowel lesions |- | [[Niacin]] || [[kg#SI multiples|mg]]/kg || 60.0 || 60.0 || || style="text-align: left;" | *Enzyme functions | style="text-align: left;" | *Deficiency **Anorexia **Weight loss **Elevated body temperature **Fiery red tongue, with ulceration and congestion |- | [[Vitamin B6]] / [[Pyridoxine]] || [[kg#SI multiples|mg]]/kg || 4.0 || 4.0 || || style="text-align: left;" | *Glucose generation *Red blood cell function *Niacin synthesis *Nervous system function *Immune response *Hormone regulation *Gene activation | style="text-align: left;" | *Deficiency **Stunted growth **Convulsive seizures **Kidney lesions |- | [[Folic Acid]] || [[kg#SI multiples|mg]]/kg || 0.8 || 0.8 || || style="text-align: left;" | *Amino acid and nucleotide metabolism *Mitochondrial protein synthesis | style="text-align: left;" | *Deficiency **Decreased growth rate **increased iron levels in blood |- | [[Biotin]]&nbsp;{{efn|name=i}} || [[kg#SI multiples|mg]]/kg || 0.07 || 0.07 || || * Supports both pregnancy and lactation<ref>NRC. 1986. Nutrient Requirements of Cats. National Academy of Sciences-National Research Council, Washington, D.C.</ref> * Carbohydrate, protein and fat metabolism<ref name=":3">Camporeale, G. and J. Zempleni. 2006. Biotin. ''In''Bowman, B.A. and Russell, R.M. (Editors) “Present Knowledge in Nutrition”, ninth edition, International Life Science Institute, Washington, D.C. Pp. 250-259.</ref> * Maintenance of blood glucose<ref name=":3" /> | * Deficiency ** Weight loss<ref name=":1">{{Cite journal|last=Carey, C., and Morris, J.|first=|date=1977|title=Biotin Deficiency in the Cat and the Effect on Hepatic Propionyl CoA Carboxylase|url=https://www.researchgate.net/profile/James_Morris4/publication/22320632_Biotin_deficiency_in_the_cat_and_the_effect_of_hepatic_propionyl_CoA_carboxylase/links/543bea950cf204cab1db521d.pdf|journal=Journal of Nutrition|volume=107|pages=330–334|via=|doi=10.1093/jn/107.2.330}}</ref> ** Secretions from the nose, mouth (saliva) and eyes begin to dry out<ref name=":1" /> ** Alopecia<ref name=":2">{{Cite journal|last=Pastoot, F., Van Herck, H., Van 'T Klooster, A., and Beynen, A.|first=|date=1991|title=Biotin Deficiency in Cats as Induced by Feeding a Purified Diet Containing Egg White|url=http://jn.nutrition.org/content/121/11_Suppl/S73.extract#|journal=American Institute of Nutrition|volume=121|pages=S73- S74|via=}}</ref> ** Dermatitis around the mouth<ref name=":2" /> * |- | [[Vitamin B12]] || [[kg#SI multiples|mg]]/kg || 0.02 || 0.02 || || style="text-align: left;" | *Enzyme functions | style="text-align: left;" | *Deficiency **Weight loss **Vomiting **Diarrhea **Intestinal disorders |- | [[Choline]] {{efn|name=j}} || [[kg#SI multiples|mg]]/kg || 2400.0 || 2400.0 || || || * Deficiency ** Fatty liver in kittens <ref name="SRM">Schaeffer, Rogers, & Morris. (1982). The choline requirement of the growing kitten in the presence of just adequate dietary methionine. ''Nutrition Research,2''(3), 289-299.</ref> ** Lower motivation to eat in kittens <ref name="SRM" /> ** Decreased growth rate in kittens <ref name="SRM" /> |- | [[Taurine]] (extruded food) || [[%]] || 0.10 || 0.10 || || * Vision<ref name="taurine">{{cite journal|access-date=2017-11-27|title=Immunologic Consequences of Taurine Deficiency in Cats|journal=Journal of Leukocyte Biology|volume=47|pages=321–331| url=https://www.ncbi.nlm.nih.gov/pubmed/2319206 |doi=10.1007/978-1-4615-3436-5_28|first1=Georgia|last1=Schuller-Lewis |first2=Pankaj D.|last2=Mehta|date=April 1990 |first3=Raul|last3=Rudelli |first4=John|last4=Sturman|pmid=2319206}}</ref> * Digestion<ref name="taurine"/> * Heart muscle function<ref name="taurine"/> * Normal pregnancy<ref name="taurine"/> * Fetal development<ref name="taurine"/> * Immunity<ref name="taurine"/> | * Deficiency ** Cardiovascular and reproductive problems<ref name="taurine"/> ** Developmental problems in the central nervous system<ref name="taurine"/> ** Retinal degeneration <ref name="taurine"/> |- | [[Taurine]] (canned food) || [[%]] || 0.20 || 0.20 || || * Vision<ref name="taurine" /> * Digestion<ref name="taurine" /> * Heart muscle function<ref name="taurine" /> * Normal pregnancy<ref name="taurine" /> * Fetal development<ref name="taurine" /> * Immunity<ref name="taurine" /> | * Deficiency ** Cardiovascular and reproductive problems<ref name="taurine" /> ** Developmental problems in the central nervous system<ref name="taurine" /> ** Retinal degeneration<ref name="taurine" /> |- ! [[Nutrient]] !! Units<br>(Dry Matter Basis) !! Growth and<br>Reproduction<br>Minimum !! Adult<br>Maintenance<br>Minimum !! Maximum !! Functions !! Signs of Deficiency/Excess |- | style="font-size:105%; text-align: left;" colspan="7" |{{resize|95%|{{center|'''NOTES'''}}}} {{notelist|notes= * {{efn|name=a| Presumes an [[energy density]] of 4.0 [[calorie|kcal]]/[[gram (unit)|g]] ME, based on the ''modified'' [[Atwater system|''Atwater'']] values of 3.5, 8.5, and 3.5 [[calorie|kcal]]/[[gram (unit)|g]] for [[protein]], [[fat]], and [[carbohydrate]] (nitrogen-free extract, NFE), respectively. Rations greater than 4.5 [[calorie|kcal]]/[[gram (unit)|g]] should be corrected for [[energy density]]; rations less than 4.0 [[calorie|kcal]]/[[gram (unit)|g]] should ''not'' be corrected for energy.}} * {{efn|name=b| Although a true requirement for [[fat]] per se has not been established, the minimum level was based on recognition of [[fat]] as a source of [[essential fatty acids]], as a carrier of [[fat-soluble vitamins]], to enhance palatability, and to supply an adequate [[caloric density]].}} * {{efn|name=c| If the mean [[urine pH]] of cats fed [[ad libitum]] is not below 6.4, the risk of [[struvite urolithiasis]] increases as the [[magnesium]] content of the diet increases.}} * {{efn|name=d| Because of very poor [[bioavailability]], [[iron]] from [[carbonate]] or [[oxide]] sources that are added to the diet should not be considered as components in meeting the minimum nutrient level.}} * {{efn|name=e| Because of very poor [[bioavailability]], [[copper]] from [[oxide]] sources that are added to the diet should not be considered as components in meeting the minimum nutrient level.}} * {{efn|name=f| Add 10 [[International units|IU]] [[vitamin E]] above minimum level per [[gram (unit)|gram]] of [[fish oil]] per kilogram of diet.}} * {{efn|name=g| [[Vitamin K]] does not need to be added unless diet contains greater than 25 [[percent]] fish on a dry matter basis.}} * {{efn|name=h| Because processing may destroy up to 90 [[percent]] of the [[thiamine]] in the diet, allowance in formulation should be made to ensure the minimum nutrient level is met after processing.}} * {{efn|name=i| [[Biotin]] does not need to be added unless diet contains [[antimicrobial]] or [[antivitamin]] compounds.}} * {{efn|name=j| [[Methionine]] may substitute [[choline]] as [[methyl donor]] at a rate of 3.75 parts for 1 part [[choline]] by weight when [[methionine]] exceeds 0.62 [[percent]].}} }} |} ==See also== * [[:Category:Cat food brands|Cat food brands]] * [[Pet food]] * [[Dental health diets for cats]] * [[Senior cat diet]] ==References== {{Reflist|2|liststyle=|refs=http://www.petsmart.com/cat/food-and-health/food/}} ==Further Information== {{Commons category}} * [https://bestcatadvisor.com/cat-food-advisor-choosing-best-cat-food/ Guide to Choose the Best Cat Food] *[https://www.vegsoc.org/factsvegetariancats Vegetarian Society UK on Vegetarian diet for cats] *[http://www.goodguide.com/categories/334088-cat-food-reviews-and-ratings Scientifically Reviewed & Rated Cat Foods at GoodGuide.com] *[http://www.alternet.org/story/18767?page=entire The Cat That Ate Tofu] Alternet article on vegan cat food *{{cite journal |author=Buffington CA |title=Dry foods and risk of disease in cats |journal=Can. Vet. J. |volume=49 |issue=6 |pages=561–3 |date=June 2008 |pmid=18624064 |pmc=2387258 }} – disputes the claim that dry food is harmful *[https://web.archive.org/web/20081017172555/http://www.api4animals.org/facts.php?p=359&more=1 Get The Facts - What's Really In Pet Food] from [[Animal Protection Institute]] {{Domestic cat}} {{DEFAULTSORT:Cat Food}} [[Category:Cats as pets]] [[Category:Pet foods]]'