Smith B P, Habasha F G, Reina-Guierra M, Hardy A J
Am J Vet Res. 1980 Dec;41(12):1947-51.
Fifty-six normal colostrum-fed Holstein-Friesian and Holstein-Friesian X Angus crossbred calves ranging in age from 3 to 9 weeks were divided into 4 vaccinated groups and 1 nonvaccinated (control) group. Group I consisted of 10 calves vaccinated 2 or 3 times subcutaneously with formalin-killed Salmonella dublin-S typhimurium bacterin with added adjuvant. Group II consisted of 4 calves vaccinated orally with formalin-killed S typhimurium daily for 21 days. Group III consisted of 17 calves given colostrum from dams which had been vaccinated twice subcutaneously with a formalin-killed S dublin-S typhimurium bacterin with added adjuvant. Group IV consisted of 8 calves orally given small doses of live virulent S typhimurium twice. Seventeen calves served as nonvaccinated controls. One to 2 weeks after the final vaccine dose (or at 3-weeks of age for group III), all calves were orally challenge exposed with virulent S typhimurium. Oral challenge dose levels ranged from 1.5 X 10(9) viable organisms to 1.5 X 10(11) viable organisms. Mortality following oral challenge exposure was 11 of 17 controls, 6 of 10 group I calves (ns), 2 of 4 group II calves (ns), 11 of 17 group III calves (ns), and 1 of 8 group IV calves (p = 0.001). Twenty calves, 4 from group I, 8 from group III, and 8 from the control group, given 1.5 X 10(11) challenge organisms (the largest challenge, inoculum) died, whereas only 1 of 6 calves in group IV given this dose died. Group II calves were not given the 1.5 X 10(11) challenge dose. Under the conditions of this experiment, bacterins given parenterally or orally to calves or given parenterally to the dams of calves did not decrease morbidity and mortality, whereas small numbers of live organisms given orally to calves were effective in lessening morbidity and mortality following oral challenge exposure with virulent S typhimurium.
56头年龄在3至9周的正常初乳喂养的荷斯坦 - 弗里生奶牛犊以及荷斯坦 - 弗里生×安格斯杂交犊牛被分为4个接种疫苗组和1个未接种疫苗（对照）组。第一组由10头犊牛组成，皮下接种2次或3次添加佐剂的福尔马林灭活都柏林沙门氏菌 - 鼠伤寒沙门氏菌菌苗。第二组由4头犊牛组成，每天口服福尔马林灭活的鼠伤寒沙门氏菌，持续21天。第三组由17头犊牛组成，这些犊牛食用的初乳来自皮下接种过2次添加佐剂的福尔马林灭活都柏林沙门氏菌 - 鼠伤寒沙门氏菌菌苗的母牛。第四组由8头犊牛组成，口服2次小剂量的活的强毒鼠伤寒沙门氏菌。17头犊牛作为未接种疫苗的对照。在最后一剂疫苗接种后1至2周（或第三组在3周龄时），所有犊牛口服强毒鼠伤寒沙门氏菌进行攻毒。口服攻毒剂量水平从1.5×10⁹个活菌到1.5×10¹¹个活菌不等。口服攻毒后的死亡率在17头对照组中为11头，第一组10头犊牛中有6头（无显著差异），第二组4头犊牛中有2头（无显著差异），第三组17头犊牛中有11头（无显著差异），第四组8头犊牛中有1头（p = 0.001）。20头犊牛，第一组4头、第三组8头和对照组8头，接受1.5×10¹¹个攻毒菌（最大的攻毒接种量）死亡，而第四组接受此剂量的6头犊牛中只有1头死亡。第二组犊牛未接受1.5×10¹¹的攻毒剂量。在本实验条件下，给犊牛经皮下或口服接种菌苗或给犊牛的母牛经皮下接种菌苗，均不能降低发病率和死亡率，而给犊牛口服少量活的菌体能有效降低口服强毒鼠伤寒沙门氏菌攻毒后的发病率和死亡率。
