Development of a Methodology for Determining the Nutritional Value of Pasture Feed Considering the Fractions of Easily Digestible Carbohydrates in the Desert Zone of Southern Kazakhstan

Due to the absence of easily digestible carbohydrates (sugar and starch, which are of great importance in animal nutrition) in the existing methods of assessing the nutritional value of feed, the need to include them in the methods for improving the overall nutritional value is a particularly urgent matter in feed manufacture for desert livestock industries. The study was carried out in the distant pastures of the Kyzylkum sandy desert and the ephemeral pastures of the foothill desert of southern Kazakhstan. The purpose of the study was to evaluate the sugar and starch content in the composition of the main forage plants and herbage to improve the methodology for determining the nutritional value of feed, considering the fractions of easily digestible carbohydrates. A total of 105 samples representing 58 different species of forage plants were analyzed for carbohydrates. As a result of the study, the content of carbohydrates in the composition of the herbage of various types of desert pastures and individual types of feed was determined. The authors established that the pasture feeds of most of the studied types of desert pastures had an average of 25 g/kg of sugar and 12 g/kg of starch in their composition at natural humidity. As the study data showed, due to the low content of easily digestible carbohydrates in the herbage of desert pastures, the provision of sheep with sugar remains at a low level, which undoubtedly affects the productivity of sheep and, in general, the efficiency indicators of animal husbandry in the region. The results of the study are of practical importance in the organization of cattle breeding in Kazakhstan and countries with similar conditions for the sheep industry.