Analysis of the relative content of probiotic bacteria in the intestines of farm animals using genetic methods

Probiotics are microorganisms that have beneficial properties that can have beneficial effects on the host organism. Chickens, pigs, and cattle are the most common farm animals around the world. In this regard, maintaining the microbial balance of the gut is an important task for veterinary medicine. It was previously established that probiotic efficacy has been proven for representatives of the genera Lactobacillus and Bifidobacterium, and Akkermansia and Faecalibacterium are considered as probiotics of a new generation. The aim of the work is a comparative analysis of the gut microbiome of chickens, pigs and cattle for the presence and relative content of probiotic microorganisms in it. Initially, the prevalence of phylum Bacteroides , Firmicutes , and Actinobacteria in the faeces of all the farm animals studied was shown. The Firmicutes phylum turned out to be the most widespread phylum isolated from chicken fecal samples, while the Bacteroides phylum dominated the gut microbiome of cows and pigs. When analyzing the relative content of proteobacteria, it was found that the intestinal microbiome of cows is represented by bacteria of the classes Betaproteobacteria and Epsilonproteobacteria , and in pigs almost exclusively by the class Epsilonproteobacteria . In the samples obtained from pigs, piglets and chickens, the dominance of bacteria of the genus Lactobacillus over Bifidobacterium was established. The simultaneous presence of probiotic bacteria of a new generation, Faecalobacterium prausnitzii and Akkermansia muciniphila , was identified only in faecal samples obtained from cows, while the relative abundance of bacteria Akkermansia muciniphila was 50.0 times higher than the number of Faecalobacterium prausnitzii in the samples. The bacterium Faecalobacterium prausnitzii was identified in pig faeces, and Akkermansia muciniphila was identified in chicken faeces. It is noteworthy that the presence of new generation probiotics in the intestines was not detected in piglets aged 5-10 days.