It was found that the phytobiotic obtained from aspen bark in the form of a decoction and an aqueous solution of lactic acid applied to the daily rate of compound feed for broiler chickens had different effects on the digestive function of broiler chickens. It was experimentally confirmed that the phytobiotic did not have a positive effect on the digestibility of feed nutrients throughout the entire period of bird rearing. It was proven that lactic acid introduced into the broiler diet by applying to feed, separately and in combination with the phytobiotic, showed a stimulating effect on the digestibility of the organic part of the feed. The greatest difference in the digestibility of crude protein, crude fat and crude fiber in six-week-old broiler chickens compared to three-weekold ones was substantiated. The calculation of the energy balance in the bird's body showed that the highest intake of exchange energy of the diet in the broiler body was observed in the group with a complex additive of phytobiotic with prebiotic at the final stage of their growth. It was spent more on the formation of products, less on maintaining vital processes. It was confirmed that the phytobiotic alone reduced the level of exchange and productive energy of the diet at the age of three weeks of broilers with a subsequent increase by the end of growth. At the same time, the prebiotic as a feed additive exhibits a higher effect of using the energy of the feed of intensively growing poultry of the meat direction of productivity in comparison with one phytobiotic. It is recommended to use the phytoprebiotic feed additive in the diet of poultry of the meat direction of productivity, increasing the digestibility of nutrients of the diet and the productive energy of the feed.

Ovchinnikov Alexander A., Mokin Artem S.

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