Mastitis in dairy cattle
Mastitis is a persistent, inflammatory reaction of the udder tissue in cows. This potentially fatal mammary gland infection is the most common disease in dairy cattle in the United States. It is also the most costly to the dairy industry.[1] Milk from cows suffering from mastitis has an increased somatic cell count.
Definition
Mastitis occurs when red blood cells (leucocytes), are released into the pertunity gland, usually in response an invasion of bacteria of the teat canal. Milk-secreting tissue, and various ducts throughout the mammary gland are damaged due to toxins by the bacteria. Mastitis can also occur as a result of chemical, mechanical, or thermal injury.
Identification
This disease can be identified by abnormalities in the udder such as swelling, heat, redness or pain. Other indications of mastitis may be abnormalities in milk such as a watery appearance, flakes, clots, or pus.[1]
Mastitis-causing bacteria
Bacteria that are known to cause mastitis include:
- Pseudomonas aeruginosa
- Staphylococcus aureus
- Staphylococcus epidermidis
- Streptococcus agalactiae[2]
- Brucella melitensis
- Corynebacterium bovis
- Mycoplasma (various species)
- Escherichia coli, (E. coli)
- Klebsiella pneumoniae
- Klebsiella oxytoca
- Enterobacter aerogenes[3]
- Pasteurella spp.[4]
- Arcanobacterium pyogenes[5]
- Proteus spp.[6]
- Prototheca zopfii (achlorophyllic algae)
- Prototheca wickerhamii (achlorophyllic algae)[6]
Types of mastitis
- Contagious mastitis
- Environmental mastitis
Transmission and prevention
Mastitis is most often transmitted by contact with the milking machine, and through contaminated hands or materials.
Effects on milk composition
Mastitis can cause a decline in potassium and lactoferrin. It also results in decreased casein, the major protein in milk. As most calcium in milk is associated with casein, the disruption of casein synthesis contributes to lowered calcium in milk. The milk protein continues to undergo further deterioration during processing and storage.[7]
Industry costs
This disease costs the US dairy industry about 1.7 to 2 billion USD each year.[7]
Treatment
Treatment is possible with long-acting antibiotics, but milk from such cows is not marketable until drug residues have left the cow's system. Antibiotics may be systemic (injected into the body), or they may be forced upwards into the teat through the teat canal.
Control
Practices such as good nutrition, proper milking hygiene, and the culling of chronically infected cows can help
See also
References
- ^ a b Department of Animal Science. "Mastitis in Dairy Cows" (PDF). MacDonald Campus of McGill University. Retrieved 4 February 2010.
- ^ "Teat Disinfection Facts". NMC. Retrieved 4 February 2010.
- ^ "A Practical Look at Environmental Mastitis". .nmconline.org/. Retrieved 4 February 2010.
- ^ "Mastitis Pathogen Notes: Pasteurella species". nmconline.org. Retrieved 4 February 2010.
- ^ "Mastitis Pathogen Notes: Arcanobacterium pyogenes". nmconline.org. Retrieved 4 February 2010.
- ^ a b "Mastitis Pathogen Notes: Proteus species". nmconline.org. Retrieved 4 February 2010.
- ^ a b Jones, G. M. "Understanding the Basics of Mastitis". Virginia Cooperative Extension. Retrieved 4 February 2010.
{{cite web}}
: Unknown parameter|coauthors=
ignored (|author=
suggested) (help)
Further reading
- Harmon, R. J. 1994. Physiology of mastitis and factors affecting somatic cell counts. J. Dairy Sci. 77:2103-2112.
- Jones, G. M., R. E. Pearson, G. A. Clabaugh, and C. W. Heald. 1984. Relationships between somatic cell counts and milk production. J. Dairy Sci. 67:1823-1831.
- Myllys, V., and H. Rautala. 1995. Characterization of clinical mastitis in primiparous heifers. J. Dairy Sci. 78:538-545.
- National Mastitis Council. 1996. Current Concepts of Bovine Mastitis, 4th ed., Arlington, VA.
- Fox LK et al. Survey of intramammary infections in dairy heifers at breeding age and first parturition. J Dairy Sci. 78; 1619–1628, 1995.
- Hallberg JW et al. The visual appearance and somatic cell count of mammary secretions collected from primigravid heifers during gestation and early postpartum. J Dairy Sci. 78; 1629-1636.
- Hogan JS et al. Efficacy of an Escherichia coli J5 bacterin administered to primigravid heifers. J Dairy Sci. 82; 939-943, 1999.
- Nickerson SC. Mastitis and its control in heifers and dry cows. International Symposium on Bovine Mastitis. Indianapolis, IN, September, 1990. pp 82–91.
- Nickerson SC et al. Mastitis in dairy heifers: Initial studies on prevalence and control. J Dairy Sci. 78;1607–1618, 1995.
- Nickerson SC et al. Efficacy of s Staphylococcus aureus bacterin in dairy herifers. An update. Proceeding of the Nat Mastitis Council Meeting. 295-6, 1998.
- Sears PM and Wilson DJ. Heifer mastitis. Bov Practitioner 28; 56-58, 1994.