Givens M Daniel, Marley M Shonda D, Jones Craig A, Ensley Douglas T, Galik Patricia K, Zhang Yijing, Riddell Kay P, Joiner Kellye S, Brodersen Bruce W, Rodning Soren P
Animal Health Research, Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA.
J Am Vet Med Assoc. 2012 Aug 15;241(4):484-95. doi: 10.2460/javma.241.4.484.
To determine whether administration of 2 doses of a multivalent, modified-live virus vaccine prior to breeding of heifers would provide protection against abortion and fetal infection following exposure of pregnant heifers to cattle persistently infected (PI) with bovine viral diarrhea virus (BVDV) and cattle with acute bovine herpesvirus 1 (BHV1) infection.
Randomized controlled clinical trial.
33 crossbred beef heifers, 3 steers, 6 bulls, and 25 calves.
20 of 22 vaccinated and 10 of 11 unvaccinated heifers became pregnant and were commingled with 3 steers PI with BVDV type 1a, 1b, or 2 for 56 days beginning 102 days after the second vaccination (administered 30 days after the first vaccination). Eighty days following removal of BVDV-PI steers, heifers were commingled with 3 bulls with acute BHV1 infection for 14 days.
After BVDV exposure, 1 fetus (not evaluated) was aborted by a vaccinated heifer; BVDV was detected in 0 of 19 calves from vaccinated heifers and in all 4 fetuses (aborted after BHV1 exposure) and 6 calves from unvaccinated heifers. Bovine herpesvirus 1 was not detected in any fetus or calf and associated fetal membranes in either treatment group. Vaccinated heifers had longer gestation periods and calves with greater birth weights, weaning weights, average daily gains, and market value at weaning, compared with those for calves born to unvaccinated heifers.
Prebreeding administration of a modified-live virus vaccine to heifers resulted in fewer abortions and BVDV-PI offspring and improved growth and increased market value of weaned calves.
确定在小母牛配种前接种2剂多价、减毒活疫苗，是否能在怀孕小母牛接触持续感染牛病毒性腹泻病毒（BVDV）的牛以及感染急性牛疱疹病毒1型（BHV1）的牛后，预防流产和胎儿感染。
随机对照临床试验。
33头杂交肉用小母牛、3头公牛、6头公牛和25头小牛。
22头接种疫苗的小母牛中有20头以及11头未接种疫苗的小母牛中有10头怀孕，并在第二次接种疫苗（在第一次接种疫苗30天后进行）102天后，与3头持续感染1a、1b或2型BVDV的公牛混养56天。在移除感染BVDV的公牛80天后，小母牛与3头患有急性BHV1感染的公牛混养14天。
接触BVDV后，1头接种疫苗的小母牛流产1头胎儿（未评估）；接种疫苗的小母牛所生的19头小牛中未检测到BVDV，而未接种疫苗的小母牛所生的所有4头胎儿（在接触BHV1后流产）和6头小牛中均检测到BVDV。两个治疗组的任何胎儿、小牛及相关胎膜中均未检测到牛疱疹病毒1型。与未接种疫苗的小母牛所生的小牛相比，接种疫苗的小母牛妊娠期更长，所生小牛的出生体重、断奶体重、平均日增重和断奶时的市场价值更高。
在小母牛配种前接种减毒活疫苗可减少流产和感染BVDV的后代数量，并改善断奶小牛的生长情况，提高其市场价值。
