[Amino acid bioconversion in the feed for broilers under different breeding rates].

Two experiments were carried out under productional conditions with a total of 69 520 broiler birds (four-line hybrids, crosses of White Plymouth Rock x Cornish ) --one in the spring and one in the summer. The birds were grown in a poultry house at density of 16.6 per sq. m. of floor area and in cage at the rate of 23.6 per sq. m. (an enclosure on the same premise). On another premise the birds were kept at 23.6 and 16.6 per sq. m., respectively. Every 15 days the amino acids and the protein were determined in the white meat, and each feed batch was checked as regards its crude protein and amino acid content. It was found that the bioconversion of the amino acids of the feed into amino acids of the white meat was acted upon by a constellation of biotic and abiotic ecologic factors. Dicisive was the effect of the biotic factors. It is stated that the present approach to optimize only the elements of the microclimate at higher rates of broiler raising is insufficient. It is necessary to study the biotic ecologic factors in detail as the base of optimization of the homotypic and heterotypic reactions.