Characteristics of alfalfa green mass of different harvests mowed in the budding phase

Purpose. To investigate and analyze the content of the essential nutrients, different carbohydrate fractions and nutritional value of green mass and prepared alfalfa hay of different harvests Methods. There were used Keldal’s method to determine crude protein content, Henneberg and Stoman’s method to determine crude gluten content, extraction method to determine crude fat content, the method of dry ashing to determine crude ash content, to investigate the content of the essential nutrients and nutritional value of alfalfa green mass of different harvests and the hay produced from it. The polarimetric method was been used to determine the content of starch and sugar and study the composition of the carbohydrate-lignin complex of alfalfa green mass and hay. Indices of neutral-detergent and acid-detergent gluten were determined according to the detergent analysis scheme. Results. Alfalfa green mass has its specific characteristics, but weather conditions have a significant effect on the content and ratio of structural carbohydrates. As a rule, the first harvesting is conducted in the budding phase in the first decade of May, the second one in the second decade of June, and the third one in the second decade of July. The latter tends to increase sugar content and the amount of easily soluble carbohydrates, and the content of hemicellulose reduces by 20—40 %. The fourth harvesting is carried out in the second decade of August and its green mass has fewer easily soluble carbohydrates, especially starch and the highest content of cellulose and lignin. Crude protein content in it is 18.97 % less and the index of crude and neutral detergent gluten content is higher on average by 20 %. Indices of non-nitrogen-extractive substances and nonstructural carbohydrates are, on the contrary, lower by 3—7 and 5—10 %, respectively. As for inorganic substances and lipids, their content is practically the same. Nutritional value is expressed in feed units on the same level in alfalfa green mass of the first three harvests and the fourth one is lower by 3—5 %. The exchange energy is also the lowest in the green mass of the fourth harvest on average by 3.7 %. Drying of alfalfa green mass in accordance with the technology provides high quality, nutrient-rich hay in which crude protein content is lower, compared with the green mass recalculated into absolute dry matter, and indicators that characterize structural carbohydrates are, on the contrary, higher.