Effects of porcine reproductive and respiratory syndrome vaccination in breeding-age animals.
Little is known about the safety and efficacy of extra-label use of the modified live porcine reproductive-and-respiratory syndrome (PRRS) virus vaccine in gestating sows. Our purpose was to determine the impact of vaccination on reproductive performance in 54 herds in Ontario, Manitoba (Canada) and the mid-western United States that were PRRS-positive, PRRS-negative, or concurrently affected by an outbreak of PRRS when initially vaccinated. Majority-vaccinated herds vaccinated > or =50% but <100% of sows at one time, and limit-vaccinated herds vaccinated <50% of sows at one time. Most majority-vaccinated herds did not vaccinate sows in late gestation, and none vaccinated during the initial PRRS outbreak. Numbers of pigs born alive and weaned decreased when pregnant sows were vaccinated. The effect of vaccination on productivity in the gestation following vaccination depended on the vaccination protocol.
Dewey
Catherine E
CE
Department of Population Medicine, Ontario Veterinary College, University of Guelph, Clinical Research Buliding, Guelph, Ont., Canada N1G 2W1. cdewey@ovcnet.uoguelph.ca
Wilson
Sophie
S
Buck
Peter
P
Leyenaar
JoAnna K
JK
D000818:Animals; D005260:Female; D015146:Midwestern United States / Q000453:epidemiology; D009864:Ontario / Q000453:epidemiology; D019318:Porcine Reproductive and Respiratory Syndrome / Q000453:epidemiology* / Q000517:prevention & control*; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology*; D011247:Pregnancy; D013552:Swine; D014611:Vaccination / Q000662:veterinary*; D014765:Viral Vaccines
D014765:Viral Vaccines