Chemical Composition of Plants as a Factor in Assessing the Nutritional Value of Forest Pastures of the North-Western Caspian Sea

Abstract

The article presents the results of an assessment of the chemical composition and nutritional value of the most common vegetation of various life forms (trees, semi-shrubs, perennial grasses) in the forest pastures of the semi-desert zone of the Northwestern Caspian Sea. The research was carried out on forested pasture areas of the Neftekumsky district of the Stavropol Territory. The basis of the research was the laboratory-field method. The twig-leaf and herbaceous phytomass of forest pastures, in accordance with its chemical indicators of organic matter content, meets zootechnical requirements. The maximum protein content is observed in spring in the woody greenery of Ulmus pumila (at the level of 18.19%) and decreases in autumn (17.4%). In addition, it was found that the twig-leaf mass of Ulmus pumila has a relatively high feed value (0.68 f.u., 8.5 Mj, digestible protein 62.67 g/kg) than herbaceous species and is a large reserve in forest pastures during drought or absence of herbaceous vegetation before the establishment of snow cover. As a result of the research, it was also found that during the dry period (summer) in the grass-grass and grass-grass phytocenoses, there is a low protein content (less than 10%) and a high fiber content (34.0–35.13%). The nutritional value of plants in general on man–made forest pastures is 0.25–0.68 fodder units, while 1 kg of feed contains 31.0–78.48 g of digestible protein. The fat content in the analyzed plants in the territory under consideration is small (1.10–4.23%), and the content of nitrogen-free extractives is quite high (30.44–65.2%) regardless of the season of the year. According to the content of macronutrients, a deficiency of phosphorus (P) was detected according to the norms. Accordingly, with constant grazing of animals in these areas, it is necessary to additionally include feed additives containing this element in the diet for the prevention of deficiency and diseases.