An investigation of the efficacy of a polyvalent mastitis vaccine using different vaccination regimens under field conditions in the United Kingdom

Bradley, A.J.; Breen, J.E.; Payne, B.; White, V.; Green, M.J.

Abstract

Vaccination can play a useful role in mastitis control programs, although there is a relative dearth of large, well-controlled field efficacy studies. This paper presents the findings on the use of a commercially available vaccine (Startvac, Hipra UK Ltd., Nottingham, UK) on commercial units under UK field conditions. In total, 3,130 cows were recruited from 7 farms and were randomly allocated, within farm, to 1 of 3 groups. The first group received the vaccine following the label regimen, the second group was vaccinated every 90 d following an initial vaccination course, and the third group was left unvaccinated to act as controls. Vaccine efficacy was assessed in the first 120 d of lactation. Data were available for analysis from 1,696 lactations in 1,549 cows. In total, 779 cases of clinical mastitis occurred in the 3 study groups, and we detected no significant difference in the incidence or prevalence of clinical or subclinical mastitis between any of the 3 groups. Mastitis vaccination following the label regimen was associated with a significant reduction in the severity of clinical cases. Cows in this group were at significantly decreased odds of developing clinical mastitis presenting with more than just milk changes [odds ratio: 0.58; 95% confidence interval (CI): 0.35–0.98]. Similarly, each additional vaccination resulted in a cow being at decreased odds of developing clinical mastitis presenting with more than just milk changes (odds ratio: 0.87; 95% CI: 0.77–0.98). Although no cows were culled because of severe mastitis in either of the vaccinated groups, we detected no significant difference in the mastitis-related culling rate between groups. Analysis of milk production data demonstrated that, on average, cows on the label regimen produced a higher volume of milk (231 L; 95% CI: 104.1–357.4) and more milk solids (12.36 kg; 95% CI: 3.12–21.60) than unvaccinated cows in the first 120 d of lactation. Conservative analysis suggested that a return on investment of 2.57:1 could be expected under UK conditions based on increased milk yield alone.

Citation

Bradley, A., Breen, J., Payne, B., White, V., & Green, M. (2015). An investigation of the efficacy of a polyvalent mastitis vaccine using different vaccination regimens under field conditions in the United Kingdom. Journal of Dairy Science, 98(3), https://doi.org/10.3168/jds.2014-8332

• Journal Article Type: Article
• Acceptance Date: Oct 9, 2014
• Online Publication Date: Dec 18, 2014
• Publication Date: Mar 1, 2015
• Deposit Date: Oct 20, 2016
• Publicly Available Date: Oct 20, 2016
• Journal: Journal of Dairy Science
• Print ISSN: 0022-0302
• Electronic ISSN: 1525-3198
• Publisher: American Dairy Science Association
• Peer Reviewed: Peer Reviewed
• Volume: 98
• Issue: 3
• DOI: https://doi.org/10.3168/jds.2014-8332
• Keywords: vaccination; mastitis; milk production; coliform; Escherichia coli
• Public URL: https://nottingham-repository.worktribe.com/output/984498
• Publisher URL: http://www.sciencedirect.com/science/article/pii/S0022030214008741
• Contract Date: Oct 20, 2016