Suckow Mark A, Haab Rudolph W, Miloscio Lawrence J, Guilloud Norman B
Laboratory Animal program, Purdue University, West lafayette, IN, USA.
J Am Assoc Lab Anim Sci. 2008 Jan;47(1):18-21.
Pasteurella multocida is a bacterial pathogen that can cause significant disease and subsequent effects on research activities involving rabbits. Although several vaccines have been tested under laboratory conditions, field trials of vaccines for the control of P. multocida in rabbits are few. We used a potassium thiocyanate extract (PTE) produced from P. multocida serotype D:3,12,15 to vaccinate Pasteurella-free rabbits at their introduction into a colony having endemic infection with P. multocida serotype A:3. Groups of 15 rabbits were vaccinated either SC or IN with 1.0 mg PTE once weekly for 3 wk. In addition a control group was sham-vaccinated IN with saline. After the last vaccine dose had been administered, rabbits were housed with the general colony of a facility with endemic pasteurellosis. Serum samples obtained before and 5 and 24 wk after the first dose of vaccine were evaluated by ELISA for anti-PTE IgG. Rabbits were euthanized if found in poor clinical condition, and all remaining rabbits were euthanized 24 wk after initial vaccination. Clinical disease typical of P. multocida infection was observed in 10 of 15 saline-vaccinated rabbits, 4 of 15 IN PTE-vaccinated rabbits, and 1 of 15 SC PTE-vaccinated rabbits. Bacterial culture of the nasopharynx at the time of necropsy was positive for P. multocida in 10 of 15 control rabbits, 5 of 15 IN PTE-vaccinated rabbits, and 1 of 15 SC PTE-vaccinated rabbits. Anti-PTE serum IgG activity had developed in both IN- and SC-vaccinated rabbits by 5 wk, with significantly lower activity by 24 wk after initial vaccination. IgG activity was significantly greater in rabbits vaccinated SC compared with controls or those vaccinated IN. In summary, PTE can be used to stimulate protective immunity to a heterologous strain of P. multocida, with stronger immunity generated by SC than IN vaccination.
多杀性巴氏杆菌是一种细菌病原体，可引发严重疾病，并对涉及兔子的研究活动产生后续影响。尽管已有几种疫苗在实验室条件下进行了测试，但针对兔子多杀性巴氏杆菌控制的疫苗田间试验却很少。我们使用从多杀性巴氏杆菌血清型D:3,12,15产生的硫氰酸钾提取物（PTE），在无巴氏杆菌的兔子引入感染多杀性巴氏杆菌血清型A:3的地方病群落时对其进行接种。将15只兔子分为一组，每周皮下或鼻内接种1.0 mg PTE，共接种3周。此外，设立一个对照组，鼻内用盐水进行假接种。在最后一剂疫苗接种后，将兔子与患有地方病性巴氏杆菌病的设施的普通群落饲养在一起。通过ELISA评估在第一剂疫苗接种前以及接种后5周和24周采集的血清样本中的抗PTE IgG。如果发现兔子临床状况不佳，则对其实施安乐死，所有剩余兔子在初次接种后24周实施安乐死。在15只接种盐水的兔子中有10只、15只鼻内接种PTE的兔子中有4只、15只皮下接种PTE的兔子中有1只观察到典型的多杀性巴氏杆菌感染临床疾病。尸检时，15只对照兔子中有10只、15只鼻内接种PTE的兔子中有5只、15只皮下接种PTE的兔子中有1只的鼻咽部细菌培养显示多杀性巴氏杆菌呈阳性。到5周时，皮下和鼻内接种的兔子均已产生抗PTE血清IgG活性，初次接种后24周时活性显著降低。与对照组或鼻内接种的兔子相比，皮下接种的兔子的IgG活性显著更高。总之，PTE可用于刺激对多杀性巴氏杆菌异源菌株的保护性免疫，皮下接种产生的免疫力比鼻内接种更强。
