Analysis of Clostridium Perfringens, C. Difficile and Pathogenic E. Coli Toxins Distribution in Feed, Gastrointestinal Tract and Milk of Healthy and Malnourished Cattle

Silage can become a source of pathogenic bacteria and their toxins, which can cause diseases and reduce the productivity of dairy cows, promoting their constant carriage and circulation within the farm. The purpose of this work was to identify relationships between the presence of toxin genes of clostridia and enterobacteria and the diversity of microbial communities in feed, gastrointestinal tract, and cattle milk, as well as to assess the possibility of circulation of pathogens and their toxins within the farm. As a result of a comprehensive analysis of the presence of clostridia and enterobacteria toxins on the farm, feed samples were examined, including the feed table and silage pit, feces and milk. Contamination with various toxins was found to be present in all samples examined. Shiga toxins of enterobacteria, C. perfringens epsilon toxin and C. difficile toxins – toxin A and binary toxin have been detected in the silage. The C. perfringens epsilon toxin and alpha toxin genes were identified in the feces of sick and healthy cows. This indicates the possibility of pathogens circulating within the farm, which can persist even in clinically healthy individuals. Significant differences in the content of important groups of microorganisms were revealed in feces. The proportion of lactobacilli that have a negative effect on metabolic processes in the rumen - the development of lactic acidosis, was 5 times higher in the feces of animals with disease, and the proportion of representatives of lactate-utilizing bacteria of the order Veillonellales-Selenomonadales in the group of healthy animals was 3 times higher, according to compared to emaciated animals. Moreover, it was demonstrated that silage may be an important reservoir of Enterobacteriaceae and Clostridia toxins, as it contained a set of genetic determinants of toxicity from both Clostridia and Enterobacteriaceae.