The former group showed the same symptoms of septicaemia as pigs infected with Salmonella alone, whereas the latter thrived without any visible symptoms of enteritis or systemic disease. PR4 counts were lower in the colon (P < 0·001) of di-associated pigs (Fig. 1a). The differences between EcN counts in the gut of mono-associated (EcN) and di-associated pigs (EcN+LT2) were not significant (Fig. 1b). Both EcN as
well as PR4 reduced Salmonella counts in the ileum (P < 0·01), and also PR4 in the colon (P < 0·05). S. Typhimurium bacteria were present in blood and all organs examined from animals infected with LT2 (Fig. 2). In contrast, neither PR4 nor EcN bacteria were found in blood click here 24 h after oral administration. EcN also interfered with translocation of S. Typhimurium into mesenteric lymph nodes (P < 0·01) (Fig. 2): S. Typhimurium was absent in blood, liver and lungs of EcN-di-associated
pigs. In contrast, all PR4-di-associated pigs suffered from septicaemia. The concentrations of IL-8, TNF-α and IL-10 learn more were measured in plasma, ileum and colon lavages of germ-free pigs, gnotobiotic pigs mono-associated with LT2 strain of S. Typhimurium, gnotobiotic pigs di-associated with EcN and LT2 and gnotobiotic pigs di-associated with PR4 and LT2. No inflammatory cytokines were found in samples from germ-free pigs (Fig. 3a–c). Plasma cytokines. IL-8 was not found in any plasma sample (Fig. 3a). LT2 induced significant IL-10 and TNF-α responses in circulation. There was no significant difference between the levels of both cytokines in plasma samples from pigs infected with LT2 alone and those from pigs associated with PR4 and LT2. Bacteraemia in piglets infected with Salmonella (Fig. 2) was
correlated highly with plasma IL-10 (r = 0·909, Fig. 4a) and TNF-α (r = 0·769, Fig. 4b) levels. A marked decrease was observed Thymidine kinase in pigs di-associated with EcN and LT2 compared to LT2 alone: IL-10 was absent in their plasma and TNF-α levels were significantly lower (Fig. 3a). Ileum cytokines. IL-8 was present in all samples infected with Salmonella, but there were no significant differences between the groups (Fig. 3b). IL-10 was not found at all. TNF-α levels were lower (P < 0·01) in pigs di-associated with EcN and LT2 than in the pigs infected with LT2 alone. In contrast, TNF-α levels in the ileum of pigs associated with PR4 and LT2 were similar to these in the pigs infected with S. Typhimurium alone. Colon cytokines. IL-8 was detected in all samples infected with Salmonella while IL-10 was not found in any sample, as in the ileum (Fig. 3c). The pre-association of pigs with commensal bacteria decreased dramatically (P < 0·01) the levels of IL-8 in Salmonella-infected pigs.