Nutritional value of the feed mass depending on the seeding rate and mowing regime of perennial legumes

The purpose of the study is to establish the optimal seeding rate and mowing mode for perennial leguminous grasses, providing high quality indicators of forage mass in the Krasnoyarsk Region. The study investigated the content of crude and digestible protein, fat, fiber, sugar, carotene in dry matter of hybrid alfalfa, meadow clover, sandy sainfoin and yellow sweet clover at different seeding rates and mowing modes. The sugar-protein ratio of perennial legumes was determined. Yellow sweet clover was sown with rates of 14 kg/ha, 18, 22 and 26 kg/ha, sandy sainfoin - with seeding rates of 60 kg/ha, 70, 80 and 90 kg/ha, hybrid alfalfa - with seeding rates of 5 kg/ha, 10, 15 and 20 kg/ha, meadow clover - with seeding rates of 5 kg/ha, 10 and 15 kg/ha. The control is the seeding rates recommended for the forest-steppe zone of the Krasnoyarsk Region: for hybrid alfalfa - 15 kg/ha, for yellow sweet clover - 22, for sandy sainfoin - 70, for meadow clover - 15 kg/ha. The studies were carried out in 2018-2020 in the phase of flowering and fruiting of herbs. Field experiments were started in 2017, for yellow sweet clover - in 2017 and 2019 at the Educational research and production complex "Borsky" (UNPK "Borsky") of the Krasnoyarsk State Agrarian University, located in the forest-steppe zone. The experiments were carried out according to the methods of the All-Russian Williams Fodder Research Institute, selection of forage grasses in Siberia and state variety testing. The nutritional value of perennial legumes was determined in the research and testing center for quality control of agricultural raw materials and food products of the Krasnoyarsk State Agrarian University. A decrease in the content of protein, fat, sugar and an increase in the content of fiber in the dry matter of perennial legumes from flowering to fruiting was revealed. The sugar-protein ratio was closer to the zootechnical norm in all studied types of grasses when mown in the flowering phase. The best sugar-protein ratio in alfalfa was at a seeding rate of 15 kg/ha - 0.5: 1.0; for sandy sainfoin at a seeding rate of 70 kg/ha - 0.7: 1.0; in clover in bloom at all seeding rates 0.4: 1.0, in sweet clover in bloom at all seeding rates - 0.5: 1.0.