The results of tests of a new combined feed additive Bioprotektin-KD based on milk thistle extract with the addition of a complex of bacteria of the genus Lactobacillus and Bifidobacterium to restore intestinal microbiota of animals are presented. Preclinical studies on the effectiveness of the feed additive were conducted on mice with experimental antibiotic-associated dysbacteriosis. Studies on the intestinal microbiota of mice revealed varying degrees of effect of different doses of feed additive on the recovery of resident microflora. The results of pre-clinical studies have proven the harmlessness, non-toxicity and efficacy of the feed additive. Clinical trials of the additive were carried out on productive animals. Its effect on the productivity of black-motley breed cows in a livestock farm in the Belgorod region was studied. The use of the functional feed additive Bioprotectin-KD had a positive effect on the milk productivity of black-motley breed cows. Cows in the experimental groups that received the feed additive had increased their milk yield per lactation by 209.41-499.01 kg compared to the control animals, which was 4.01-8.78%. The quality indicators of milk have increased. The composition of the microflora of the experimental (feed supplement recipients) and control calves was studied. It was found that the quantitative composition of probiotic flora in the intestines of young calves of the control group remained practically unchanged throughout the experiment. The number of indigeneous microflora (lactobacilli and bifidobacteria) increased in the experimental animals. The content of lactic acid microorganisms in the experimental calves began to increase on day 6 of feed supplementation and reached physiological norm on day 30. The safety index of the product has been calculated. The use of the functional feed additive Bioprotektin-KD in conditions of a livestock complex has improved such production indicators as calf survival, average daily weight gain, and milk productivity of cows in the experimental groups of animals as compared to the control ones.
Use of biological nano zinc as a feed additive in quail nutrition: biosynthesis, antimicrobial activity and its effect on growth, feed utilisation, blood metabolites and intestinal microbiota
