For example, vaccination may increase circulating antibodies in the blood stream against certain mastitis pathogens to prevent or limit bacterial growth after invasion into a mammary quarter. The resulting enhanced immunity may also minimize pathogen damage to milk-producing tissues, modify the inflammatory response, promote tissue repair, and reduce the clinical expression of disease. A list of bacteria isolated from clinical cases of mastitis is shown in Figure 1.
Progress has been made in efforts to develop vaccines for preventing both contagious and environmental mastitis. There are commercial mastitis vaccines currently available for E. Far less information is available on streptococcal vaccines, and there are currently none commercially available. Table 1. Percentage of dairy operations that use vaccines to control mastitis, by herd size. The most success in vaccinating cows against mastitis has been realized with gram-negative common core vaccines, which means that the vaccine is meant to target a common portion of many gram-negative pathogens.
Bacterins killed or attenuated bacterial preparations formulated against coliforms e. This may be due to: 1 the trend for low somatic cell count SCC milk; 2 an increase in cow susceptibility to coliform mastitis; and 3 higher density housing, which increases exposure to environmental pathogens. Coliform mastitis may range in severity from subclinical infections to peracuteclinical cases.
A high proportion of clinical cases occurs within the first three months of lactation, mainly during the first two weeks after calving, causing marked losses in milk production, e. Therefore, it is important that the dairy farmer avoid the disease or minimize the risk of infection in the herd. How widespread is coliform vaccine use? An examination of the percentage of operations that administer mastitis vaccines by U. Table 2. Percentage of operations that administered mastitis vaccines by region.
Control of coliform mastitis has been made possible through the development of mutant gram-negative bacteria. Vaccines used to combat gram-negative pathogens focus on using the mutant gram-negative core antigen, which lacks the chains that protect the lipopolysaccharides of gram-negative pathogens. This characteristic is important because the antibodies produced by the vaccinated animals are specific to the exposed lipopolysaccharides of all gram-negative organisms whether they are of the genus Escherichia, Klebsiella , or Enterobacter.
Thus, such vaccines stimulate the production of antibodies against common core antigens in the bacterial cell wall that are cross-protective against a wide variety of gram-negative microorganisms. Three such vaccines are described below. Vaccination is a tool that can be used very effectively to help reduce the incidence of disease in a cow herd.
As with all tools, vaccinations must be administered correctly to get the full benefit. Proper timing, route of administration, dosage, and type of vaccine are paramount to preventing disease. Beef quality assurance guidelines should be followed whenever vaccines or medications are administered. Your veterinarian can help you develop a vaccination program specifically for your operation and geographic area.
The following protocols are suggested for a fall vaccination program. NOTE: In the fall, bred replacement heifers should be vaccinated using the same protocol as the mature cows.
John C. He earned his B. A vaccination program for a dairy cow can be much different than one for a pastured beef cow. Different types of vaccines are also available, with antiserums and modified live viral vaccines two of the most common. Table 5 outlines the recommended vaccination program for dairy herd bulls.
It is suggested that producers purchase only virgin bulls from reliable sources with known vaccination histories, and these bulls should have negative test results for persistent BVD virus infection, brucellosis, and tuberculosis depending on local and state requirements.
All herd additions should also undergo a minimum isolation period of 30 days and preferably 60 days. All bulls should have been designated as satisfactory potential breeders, utilizing the standard breeding soundness examination, prior to exposure to breeding females. It is important that the owner and veterinarian develop a vaccination program tailored to fit the needs of the herd, and that it is implemented within current or proposed management practices.
Vaccines, vaccine selection, and proper vaccine and equipment handling are only one component of a well-structured herd health program. If there is an absence of proper biosecurity inter-herd and biocontainment intra-herd practices, proper nutrition, and proper management of environmental conditions and other stress factors, any well-planned vaccination program may be ineffective.
Always include a veterinarian in preventative herd health decisions, and always read and adhere to product instructions and precautions. A guide to the best management practices to protect livestock from outside wildlife in relation to their fencing and water quality.
A description of the most common respiratory diseases horses may contract and ways to treat them including how to prevent spreading. Identification, treatment and prevention of the West Nile Virus in horses. A guide to executing effective purchase exams for horses and lists what these exams usually entail. By Dan N. Waldner, John Kirkpatrick, Terry W. Modified-live vaccines Killed inactivated vaccines Provide longer duration and more complete immunity Provide short-lived systemic immunity May produce better cellular and secretory immunity May provide limited cellular and secretory immunity Do not require multiple vaccinations for immunologic memory Often require revaccination to ensure immunologic memory Often do not require revaccinating or require fewer revaccinations during the life of an animal Require multiple vaccinations to maintain active immunity Rarely causes hypersensitivities, but may be virulent to certain individual animals or may cause animals to produce clinical signs of disease Can cause hypersensitivity reactions When used on pregnant animals some abortions may occur depending on the particular viral agent Cannot cause disease even in immunologically compromised animals.
Follow label directions Coliform mastitis Bacterin. Was this information helpful?
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