Mukkur T K, Walker K H, McDowell G H
CSIRO Division of Animal Health, McMaster Laboratory, Glebe NSW, Australia.
Comp Immunol Microbiol Infect Dis. 1998 Oct;21(4):327-36. doi: 10.1016/s0147-9571(97)00021-0.
Lambs sucking non-immunised ewes or ewes immunised 4-5 weeks before lambing with live attenuated, aromatic-dependent (aroA) Salmonella typhimurium (strain CS 332) were challenged orally at either 2, 4 or 7 days of age with virulent S. typhimurium (strain CS 94) at doses ranging from 10(9) to 10(13) colony forming units. No lambs displayed signs of clinical salmonellosis and all survived challenge but those sucking immunised ewes had organisms of the challenge strain in their faeces for much shorter periods of time than lambs of the control ewes. High titres of specific antibodies were measured in colostrum and milk of immunised ewes in comparison with very low titres measured in samples from control ewes; these differences were reflected by the titres of antibodies in the sera of corresponding lambs. At 2 days after lambing, the major antibody isotype in the colostrum of immunised ewes and sera of their lambs was IgM whereas at 7 days IgG1 was the predominant isotype. While it was clear that vaccination of pregnant ewes with the live attenuated vaccination conferred protection against experimentally-induced salmonellosis in their lambs, considerable protection was observed in control lambs in spite of there being very low titres of antibodies in the mammary secretion of their dams. The latter observation could be related to the presence of contain non-antibody potent bactericidal factors previously described in colostrum and milk.
用减毒活的、芳香族依赖型（aroA）鼠伤寒沙门氏菌（菌株CS 332）在产羔前4 - 5周免疫的母羊或未免疫的母羊所哺乳的羔羊，在2、4或7日龄时经口用剂量范围为10⁹至10¹³菌落形成单位的强毒鼠伤寒沙门氏菌（菌株CS 94）进行攻毒。没有羔羊表现出临床沙门氏菌病的症状，所有羔羊在攻毒后均存活，但那些吸吮免疫母羊乳汁的羔羊粪便中攻毒株的存在时间比对照母羊所产羔羊粪便中的攻毒株存在时间短得多。与对照母羊样本中测得的极低抗体滴度相比，免疫母羊的初乳和乳汁中测得高滴度的特异性抗体；相应羔羊血清中的抗体滴度也反映了这些差异。产羔后2天，免疫母羊初乳及其羔羊血清中的主要抗体同种型是IgM，而在7天时IgG₁是主要同种型。虽然很明显用减毒活疫苗对怀孕母羊进行免疫可为其羔羊提供针对实验性诱导的沙门氏菌病的保护，但在对照羔羊中也观察到了相当程度的保护，尽管其母羊乳腺分泌物中的抗体滴度非常低。后一观察结果可能与初乳和乳汁中先前描述过的含非抗体强效杀菌因子的存在有关。
