Poester Fernando P, Gonçalves Vítor S P, Paixão Tatiane A, Santos Renato L, Olsen Steven C, Schurig Gerhardt G, Lage Andrey P
Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte - MG, Brazil.
Vaccine. 2006 Jun 19;24(25):5327-34. doi: 10.1016/j.vaccine.2006.04.020. Epub 2006 Apr 27.
With the goal of providing an additional tool for controlling bovine brucellosis in Brazil and evaluating the full calf dose in adult cattle, the efficacy of the rough Brucella abortus strain RB51 vaccine was tested in heifers. Thirty-three females of approximately 24 months of age were divided in two groups: one group (n=20) received the RB51 vaccine and the other group (n=13) were used as non-vaccinated control. Animals in the vaccinated group were split in two sub-groups. One sub-group (n=12) was vaccinated subcutaneously with 1.5x10(10) colony forming units (CFU) of RB51 at Day 0 of the experiment and the other sub-group (n=8) was vaccinated subcutaneously with 1.6x10(10) CFU of RB51 at 60 days of gestation (Day 260 of the experiment). All cattle were challenged between 6 and 7 months of pregnancy with 3x10(8) CFU of the virulent strain 2308 of B. abortus by the conjunctival route. Vaccination with RB51 vaccine did not result in the production of any antibodies against the O-side chain of lipopolysaccharide (LPS), as measured by conventional serological tests (rose bengal plate agglutination test (RBPAT), standard tube agglutination test (STAT), and 2-mercaptoethanol test (2ME)). A total of 25% cumulative incidence of abortions was found in the vaccinated group, whereas in the control group the cumulative incidence was 62%. B. abortus RB51 was not isolated from any sample, and no abortions were produced by RB51 vaccination of females at 60 days of pregnancy. The results indicate that vaccination with RB51 prevented 59.4% of abortions, 58.6% of cow infections, and 61.0% of fetal infections. The relative risk (RR) revealed that non-vaccinated animals have 2.462 (95% CI 1.029-5.889) times higher risk of aborting than RB51-vaccinated animals.
为了提供一种控制巴西牛布鲁氏菌病的额外工具，并评估成年牛的全犊剂量，在小母牛中测试了粗糙型布鲁氏菌RB51疫苗的效力。将33头约24月龄的雌性牛分为两组：一组（n = 20）接种RB51疫苗，另一组（n = 13）用作未接种疫苗的对照。接种疫苗组的动物再分为两个亚组。一个亚组（n = 12）在实验第0天皮下接种1.5×10¹⁰菌落形成单位（CFU）的RB51，另一个亚组（n = 8）在妊娠60天（实验第260天）皮下接种1.6×10¹⁰CFU的RB51。所有牛在妊娠6至7个月时通过结膜途径用3×10⁸CFU的布鲁氏菌强毒株2308进行攻毒。通过常规血清学检测（玫瑰红平板凝集试验（RBPAT）、标准试管凝集试验（STAT）和2-巯基乙醇试验（2ME））测定，接种RB51疫苗未产生任何针对脂多糖（LPS）O侧链的抗体。接种疫苗组的流产累积发生率为25%，而对照组的累积发生率为62%。未从任何样本中分离出布鲁氏菌RB51，在妊娠60天给雌性牛接种RB51也未导致流产。结果表明，接种RB51可预防59.4%的流产、58.6%的母牛感染和61.0%的胎儿感染。相对风险（RR）显示，未接种疫苗的动物流产风险比接种RB51疫苗的动物高2.462倍（95%可信区间1.029 - 5.889）。
