Effect of Eimeria maxima infection upon the invasion of Salmonella serovar typhimurium through the intestine of chicken.

Abstract

Two experiments were conducted to examine invasion of salmonella through the intestine of chickens infected with Eimeria maxima. In experiment 1, 1.6-4.0×105 Salmonella serovar typhimurium (S. typhimurium) were injected into the small-intestinal loop established in E. maxima-infected and -uninfected chickens under anesthesia, and cardiac blood, spleen and liver were examined for the presence of S. typhimurium. The organism was more frequently recovered from these samples, particularly from spleen 10 days after coccidial inoculation, than from the samples of uninfected birds given only S. typhimurium into small-intestinal loop. When S. typhimurium was injected into small-intestinal loop or ligated cecum of intact chickens, more samples were positive for S. typhimurium from small-intestinal loop than those from ligated cecal group. Significant difference was seen in the spleen samples. In experiment 2, number of S. typhimurium in cardiac blood, spleen and liver was counted after injection of 1.8-8.4×107 S. typhimurium into small-intestinal loop of chickens 10 days after E. maxima inoculation. The counts in spleen were approximately 102 CFU/g 3 hr after the injection and were higher than those in liver and blood of both E. maxima infected and uninfected birds. In liver, the counts in E. maxima infected birds 30 min after the injection were significantly higher than those in uninfected birds. In cardiac blood, a few S. typhimurium were recovered from E. maxima infected birds, whereas no organism was found from uninfected birds until 2 hr after the injection. It is concluded that in chickens salmonella penetrated more readily through small intestine than ceca, and E. maxima infection enhanced the penetration.