Osterberg J, Wallgren P
National Veterinary Institute, Uppsala, Sweden.
Vet Rec. 2008 May 3;162(18):580-6. doi: 10.1136/vr.162.18.580.
The epidemiology of a feed-associated Salmonella serotype (Salmonella Yoruba) was compared with that of a 'classical' serotype (Salmonella Typhimurium) by inoculating pigs aged 10 weeks with 0.65 x 10(3), 0.65 x 10(6) or 0.65 x 10(9) colony-forming units (cfu) of either serotype. The pigs were then monitored for eight weeks with respect to the faecal excretion of Salmonella species and the presence of serum antibodies. Only minor differences were observed between the two serotypes but the dose inoculated had significant effects. The pigs inoculated with 0.65 x 10(9) cfu shed Salmonella species in faeces constantly for four weeks, and intermittently during the subsequent four weeks; the pigs inoculated with 0.65 x 10(6) cfu shed Salmonella species intermittently for four weeks, but not for longer, and the pigs inoculated with 0.65 x 10(3) cfu generally did not excrete Salmonella species. The pigs inoculated with 0.65 x 10(9) cfu S Typhimurium seroconverted at a high titre within two weeks, the pigs inoculated with 0.65 x 10(6) cfu seroconverted later and with lower titres of antibodies, and the pigs inoculated with 0.65 x 10(3) cfu did not seroconvert. A similar pattern was observed with S Yoruba, but the responses were slower and at lower titres.
通过给10周龄的猪接种0.65×10³、0.65×10⁶或0.65×10⁹菌落形成单位（cfu）的两种血清型沙门氏菌（饲料相关的约鲁巴沙门氏菌血清型和“经典”血清型鼠伤寒沙门氏菌），比较了这两种血清型沙门氏菌的流行病学特征。然后对猪进行为期八周的监测，观察沙门氏菌属在粪便中的排泄情况以及血清抗体的存在情况。两种血清型之间仅观察到微小差异，但接种剂量有显著影响。接种0.65×10⁹ cfu的猪连续四周在粪便中排出沙门氏菌属，随后四周间歇性排出；接种0.65×10⁶ cfu的猪间歇性排出沙门氏菌属四周，但时间不长，接种0.65×10³ cfu的猪一般不排出沙门氏菌属。接种0.65×10⁹ cfu鼠伤寒沙门氏菌的猪在两周内血清转化为高滴度抗体，接种0.65×10⁶ cfu的猪血清转化较晚且抗体滴度较低，接种0.65×10³ cfu的猪未发生血清转化。约鲁巴沙门氏菌也观察到类似模式，但反应较慢且滴度较低。
