Nielsen B, Baggesen D, Bager F, Haugegaard J, Lind P
Danish Veterinary Laboratory, Copenhagen V, Denmark. bn/svs.dk
Vet Microbiol. 1995 Dec;47(3-4):205-18. doi: 10.1016/0378-1135(95)00113-1.
A total of 43 pigs, inoculated with Salmonella typhimurium (O:1,4,5,12) and un-inoculated controls were followed weekly by blood and faecal samplings for up to 18 weeks post inoculation (p.i.). Three pigs, inoculated with S. infantis (O:6,7) were followed similarly for 9 weeks. All inoculated pigs, except one, were positive for Salmonella by traditional faecal culture on at least one occasion during the first week of infection, whereafter shedding of bacteria rapidly declined to < 10% of the pigs from week 7. All control pigs remained Salmonella negative by culture of faecal samples. When examined serologically in an indirect ELISA using mixed purified LPS from S. typhimurium and S. choleraesuis (O:6,7), all but one S. typhimurium infected pig and all S. infantis infected pigs produced significantly increased optical densities (OD) in the ELISA as compared to the control groups. The maximum anti-LPS response was observed at day 22, when 86% of the S. typhimurium inoculated pigs had seroconverted, while the frequency of seropositive pigs peaked at days 30 (92%) and 37 p.i. (92%). Large variations were found among pigs concerning time of seroconversion (between 6 and 37 days p.i.), maximum OD-level attained (between 8 and 130% of a reference serum) and persistence of reaction. At the time of necropsy, 18 weeks p.i., 67% of the S. typhimurium inoculated pigs were found seropositive, while 100% of the S. infantis inoculated pigs were found seropositive at necropsy, 9 weeks p.i. Salmonella in internal organs were detected at necropsy in 4/22 of the S. typhimurium inoculated pigs with persistent anti-LPS reaction and all 3 S. infantis inoculated pigs but in none of the antibody-negative pigs. The ELISA is therefore suitable for screening for the presence of infection with S. typhimurium or S. infantis on a herd basis. Its suitability for other serotypes of Salmonella will require further testing.
总共43头接种鼠伤寒沙门氏菌（O:1,4,5,12）的猪和未接种的对照猪，在接种后（p.i.）每周进行血液和粪便采样，持续18周。3头接种婴儿沙门氏菌（O:6,7）的猪以类似方式跟踪9周。除1头猪外，所有接种猪在感染第一周内至少有一次通过传统粪便培养沙门氏菌呈阳性，此后细菌排出量从第7周开始迅速下降至<10%的猪。所有对照猪粪便样本培养沙门氏菌均为阴性。当使用来自鼠伤寒沙门氏菌和猪霍乱沙门氏菌（O:6,7）的混合纯化脂多糖在间接ELISA中进行血清学检测时，除1头感染鼠伤寒沙门氏菌的猪外，所有感染鼠伤寒沙门氏菌的猪和所有感染婴儿沙门氏菌的猪与对照组相比，ELISA中的光密度（OD）显著增加。在第22天观察到最大抗脂多糖反应，此时86%接种鼠伤寒沙门氏菌的猪已血清转化，而血清阳性猪的频率在接种后第30天（92%）和第37天（92%）达到峰值。猪之间在血清转化时间（接种后6至37天之间）、达到的最大OD水平（参考血清的8%至130%之间）和反应持续时间方面存在很大差异。在接种后18周尸检时，67%接种鼠伤寒沙门氏菌的猪血清呈阳性，而在接种后9周尸检时，100%接种婴儿沙门氏菌的猪血清呈阳性。在尸检时，在4/22有持续抗脂多糖反应的接种鼠伤寒沙门氏菌的猪和所有3头接种婴儿沙门氏菌的猪的内脏中检测到沙门氏菌，但抗体阴性的猪中未检测到。因此，ELISA适用于在群体基础上筛查鼠伤寒沙门氏菌或婴儿沙门氏菌感染的存在。其对其他沙门氏菌血清型的适用性需要进一步测试。
