Some aspects of dairy cows mineral nutrition in the Republic of Dagestan

The purpose of research is to study the mineral composition of forage plants in the plain zone of the Republic of Dagestan for the development of effective, environmentally friendly, mineral preparations, premixes, additives and licks briquettes that normalize metabolic processes in the body of animals. The selection and analysis of feeds that make up the diets of cows in different periods have been carried out. Samples of feed ration were examined for the content of macro- and microelements. The dry matter was determined by a conventional method. The content of macro- and microelements was determined on an atomic absorption spectrophotometer "Quantum 2A", inorganic phosphorus – by the vanadate-molybdenum method, iodine – by the kinetic thiocyanate-nitrate method. The obtained research results indicate that pasture vegetation, harvested feed and rations of dairy cows have a deficiency of a number of vital macro- and microelements. The article provides data on the content of macro- and microelements in pasture vegetation, harvested feed and rations of dairy cows at different periods of their keeping. It has been established that the content of mineral substances in them does not provide the physiological need of cows, which in the future may cause the development of macro- and microelementosis of alimentary origin. There was revealed a deficiency in the diet of cows in the autumn-winter period of keeping of Na, Mg, P, Fe, Mn, Zn, Cu, Co, Se and I, respectively, by 54.50; 6.28; 42.83; 43.59; 43.06; 50.10; 35.50; 71.0; 49.72; 75.64 %, with an excess of K and Ca, respectively, at 193.30 and 24.30; in the spring-summer peri-od Na – by 44.0; Mg is normal, P – 35.53; Fe – 33.63; Mn 13.58; Zn 31.27; Cu 24.21; Co 25.51; Se 30.10; I – 46.66 % with an excess content of K and Ca, respectively, by 241.68 and 122.80 %. It was found that in the diets of cows in the autumn-winter period of keeping the ratio of K:Na; Ca:P the average was, respectively, 27.8: 1; 3.45: 1, spring-summer, respectively – 25.99: 1; 5.48: 1 at a rate of 3-5: 1; 2: 1.