Lord V R, Schurig G G, Cherwonogrodzky J W, Marcano M J, Melendez G E
Laboratorio de Brucelosis, indtituto de investigaciones Veterinarias, Maracay, Venezuela.
Am J Vet Res. 1998 Aug;59(8):1016-20.
To assess humoral and protective immunity in cattle vaccinated by 12 months with Brucella abortus vaccine strains RB51 and 19 under field conditions of high and low brucellosis prevalence.
450 seronegative female cattle: 330 three to eight months old (calves), and 120 ten to twelve months old (heifers).
Ranch A had high prevalence (39%) of brucellosis, and ranch B had low prevalence (2%), as determined by results of conventional serologic testing: agar gel immunodiffusion and the ring test. Seronegative cattle were vaccinated once or twice with 5 x 10(9) colony-forming units of B abortus strain RB51 or once with strain 19. After vaccinating 285 cattle with strain RB51 and 165 with strain 19, 74 (26%) and 30 (18%), respectively, were bred to seropositive bulls, then were kept within the infected herd of origin.
All cattle vaccinated with strain 19 seroconverted 30 days later. All 285 cattle vaccinated with strain RB51 had negative results for all serologic tests, including agar gel immunodiffusion. All RB51-vaccinated cattle that became pregnant had negative results for the ring test and for conventional serologic tests after their first calving.
Strain RB51 can be used as a live organism vaccine without inducing antibody titers that interfere with serodiagnosis, and induced 100% protection against field strain B abortus-induced abortion in cattle vaccinated at least 1 year before mating to an infected bull. Vaccination with strain 19 under similar conditions was less effective than vaccination with strain RB51.
在布鲁氏菌病高流行率和低流行率的野外条件下，评估用流产布鲁氏菌疫苗株RB51和19免疫12个月的牛的体液免疫和保护性免疫。
450头血清学阴性的母牛：330头3至8月龄（犊牛），120头10至12月龄（小母牛）。
根据传统血清学检测结果（琼脂凝胶免疫扩散试验和环状试验）确定，牧场A布鲁氏菌病流行率高（39%），牧场B流行率低（2%）。血清学阴性的牛用5×10⁹ 菌落形成单位的流产布鲁氏菌RB51株免疫一次或两次，或用19株免疫一次。在用RB51株免疫285头牛和用19株免疫165头牛后，分别将74头（26%）和30头（18%）与血清学阳性公牛配种，然后留在原感染牛群中。
所有用19株免疫的牛在30天后血清阳转。所有用RB51株免疫的285头牛所有血清学检测结果均为阴性，包括琼脂凝胶免疫扩散试验。所有怀孕的用RB51株免疫的牛在首次产犊后环状试验和传统血清学检测结果均为阴性。
RB51株可作为活生物体疫苗，不诱导干扰血清学诊断的抗体滴度，并在与感染公牛交配前至少1年免疫的牛中诱导100%抵抗野外流产布鲁氏菌菌株诱导流产的保护作用。在类似条件下用19株免疫不如用RB51株免疫有效。
