Davis D S, Templeton J W, Ficht T A, Williams J D, Kopec J D, Adams L G
Department of Veterinary Pathology, College of Veterinary Medicine, Texas A&M University, College Station 77843.
J Wildl Dis. 1990 Jul;26(3):360-71. doi: 10.7589/0090-3558-26.3.360.
Two groups of six, non-brucellosis vaccinated, brucellosis seronegative pregnant American bison (Bison bison) were individually challenged with 1 x 10(7) colony forming units (CFU) of Brucella abortus strain 2308. Three days after challenge, each bison group was placed in a common paddock with six non-vaccinated, brucellosis susceptible, pregnant domestic heifers. In a parallel study, two groups of six susceptible, pregnant cattle were simultaneously challenged with the identical dose as the bison and each group was placed with six susceptible cattle in order to compare bison to cattle transmission to that observed in cattle to cattle transmission. Blood samples were collected from bison and cattle weekly for at least 1 mo prior to exposure to B. abortus and for 180 days post-exposure (PE). Sera from the bison and cattle were evaluated by the Card, rivanol precipitation, standard plate agglutination, standard tube agglutination, cold complement fixation tube, warm complement fixation tube, buffered acidified plate antigen, rapid screening, bovine conjugated enzyme linked immunosorbent assay, bison or bovine conjugated enzyme linked immunosorbent assay, and the hemolysis-in-gel techniques for the presence of antibodies to Brucella spp. At the termination of pregnancy by abortion or birth of a live-calf, quarter milk samples, vaginal swabs, and placenta were collected from the dam. Rectal swabs were collected from live calves, and mediastinal lymph nodes, abomasal contents and lung were taken at necropsy from aborted fetuses for culture of Brucella spp. These tissues and swabs were cultured on restrictive media for the isolation and identification of Brucella spp. Pathogenesis of brucellosis in bison was studied in an additional group of six pregnant bison which were challenged with 1 x 10(7) CFU of B. abortus strain 2308. One animal was euthanatized each week PE. Tissues were collected at necropsy and later examined bacteriologically and histologically. Lesions of brucellosis in bison did not significantly differ grossly or histologically from those in cattle. There were six abortions and two nonviable calves in the bison group, as compared to nine abortions in the 12 similarly inoculated cattle. As determined by bacterial isolations, transmission of B. abortus from bison to cattle (five of 12 susceptible cattle became infected) did not differ statistically from cattle to cattle transmission (six of 12 susceptible cattle became infected) under identical conditions. No single serologic test was constantly reliable to diagnosing B. abortus infected bison for 8 wk PE.(ABSTRACT TRUNCATED AT 400 WORDS)
选取两组，每组六头未接种布鲁氏菌病疫苗、布鲁氏菌病血清学阴性的怀孕美洲野牛（美洲野牛），分别用1×10⁷个流产布鲁氏菌2308菌株的菌落形成单位（CFU）进行个体攻毒。攻毒三天后，将每组美洲野牛与六头未接种疫苗、易感染布鲁氏菌病的怀孕家养小母牛放在同一个围栏中。在一项平行研究中，两组各六头易感染布鲁氏菌病的怀孕母牛同时用与美洲野牛相同剂量的菌液进行攻毒，并且每组与六头易感染的母牛放在一起，以便比较美洲野牛与牛之间的传播情况和牛与牛之间的传播情况。在接触流产布鲁氏菌之前至少1个月每周从美洲野牛和母牛采集血样，并在接触后（PE）180天内每周采集。通过卡片试验、利凡诺沉淀试验、标准平板凝集试验、标准试管凝集试验、冷补体结合试管试验、热补体结合试管试验、缓冲酸化平板抗原试验、快速筛查试验、牛缀合酶联免疫吸附试验、美洲野牛或牛缀合酶联免疫吸附试验以及凝胶溶血技术评估美洲野牛和母牛血清中布鲁氏菌属抗体的存在情况。当怀孕母牛因流产或产下活犊而终止妊娠时，从母体采集四分奶样、阴道拭子和胎盘。从活犊采集直肠拭子，对流产胎儿进行尸检时采集纵隔淋巴结、皱胃内容物和肺组织用于布鲁氏菌属培养。将这些组织和拭子接种在选择性培养基上以分离和鉴定布鲁氏菌属。在另一组六头怀孕美洲野牛中研究了美洲野牛布鲁氏菌病的发病机制，这些野牛用1×10⁷CFU的流产布鲁氏菌2308菌株进行攻毒。在攻毒后每周对一头动物实施安乐死。在尸检时采集组织，随后进行细菌学和组织学检查。美洲野牛布鲁氏菌病的病变在大体和组织学上与牛的病变没有显著差异。美洲野牛组有六次流产和两头未存活的犊牛，相比之下，12头同样接种的牛中有九次流产。通过细菌分离确定，在相同条件下，流产布鲁氏菌从美洲野牛传播到牛（12头易感染牛中有五头被感染）与牛与牛之间的传播（12头易感染牛中有六头被感染）在统计学上没有差异。在攻毒后8周内，没有一种血清学检测方法能始终可靠地诊断出感染流产布鲁氏菌的美洲野牛。（摘要截短至400字）
