Digestibility of nutrients in quails at different levels of energy in feed

Abstract
The relevance of the study is due to the limited existing research, mainly on Japanese quails, the lack of data on the dynamics of changes in nutrient use during the productive cycle of meat quails and the impact of energy levels. The aim of the study is to study the dynamics and relationship of feed nutrient digestibility with energy levels of pharaoh laying quails. The experiment was conducted by the method of groups. According to the scheme of the experiment at the age of 45 days, 150 quails were selected, from which, according to the principle of analogous groups, 5 groups were formed – control and 4 experimental, 30 heads (25 females and 5 males) in each. The level of metabolic energy in the feed of the control group was 13.4 MJ / kg, the 2nd group – 10.7 MJ, the 3rd group – 12.1 MJ, the 4th group – 14.7 MJ, the 5th group – 16.1 MJ Quails of all groups received loose complete feed, compiled according to special recipes. During the experiment, three series of physiological experiments were conducted to study the digestibility of nutrients. For this purpose, three laying hens at 116, 200 and 284 days of age were selected from each group according to the principle of analogues. Zootechnical analysis of samples was carried out according to generally accepted methods according to the Weende analysis scheme. It is established that the use of compound feeds with different content of metabolic energy affects the digestibility of nutrients. The highest levels of nutrient utilization were observed when feeding feed with a metabolic energy content of 1.34 MJ. The nature of the changes depends largely on the age of the quails. The absence of a noticeable difference in digestibility during 2-5 months of laying for feeding feeds with an energy content of 1.09 to 1.34 MJ is a prerequisite for the development of special feeding programs aimed at minimizing costs. The presence of insignificant influence of the level of energy nutrition of quails on the digestibility of protein (rs = - 0.34, P> 0.1) was noted. The age of quails is inversely related to protein digestibility (rs = - 0.57; P <0.05).