The influence of caprylic acid on counts of salmonellas and coliforms in chickens experimentally infected with Salmonella enteritidis

Medium-chain fatty acids are efficient antimicrobial agents. In our in vitro experiments, caprylic acid (C 8:0) was found the most effective fatty acid against salmonellas. The aim of this study was to evaluate the effect of caprylic acid on counts of salmonellas and coliforms in chickens experimentally infected with Salmonella enteritidis. Fourteen days old chickens were fed a commercially available diet. Treatment groups received a diet supplemented with 0.25 % and 0.5 % of caprylic acid. The feed of treated birds was infected with 5 ml of overnight-grown bacterial culture per one kilogram of feed. On the eighth day of the experiment, chickens were slaughtered and crop and cloaca contents sampled for microbiological analyses. Differences between control and treated samples were evaluated by the Student ́s t-test. Caprylic acid at both concentrations significantly decreased counts of salmonellas and coliforms in all samples, the effect of caprylic acid in the crop contents, however, was more pronounced. Antibacterial activity of caprylic acid was dose-dependent. It can be concluded that caprylic acid is able to reduce numbers of salmonellas in the gastrointestinal tract of chickens and has a potential to improve health status of infected animals.