Activity of blood plasma enzymes and the productive quality of animals depending on the level of protein and energy in the ration of lactating ewes

We studied the milk production, the condition of nutritional status, the intensity of growth and development of suckling lambs and the activity of individual enzymes in the blood plasma  with optimization of the level of protein and energy in rations of lactating ewes of Ascanian meat and wool breed in the Foothills of the Carpathians. It is known, that the geochemical zone of the Carpathian region is characterized by specific protein composition and energy value of feeds. Therefore, studies aimed at adjusting the rations of pregnant and lactating ewes of the Askanian breed in this zone according to the level of protein and energy in the winter-stall period and their influence on the productive qualities and course of metabolism in animals, have an important scientific and practical significance. The study was carried out on 2 groups of lactating ewes-analogues (10 heads each) of Askanian meat and wool breed with crossbred wool in the  «Hrusyatychi» Farm of the Institute of Agriculture of the Carpathian region of the National Academy of Sciences, during the stall period. The duration of the experiment is 90 days. The diet of the ewes of the control group consisted of 1.6 kg of hay meadow, 0.5 kg of whole grain of oats and 0.5 kg of compound feed according to the prescription K80-6-89, the research group's ewes received experimental mixed feeds, in which the part of the grain base was replaced with pea bran, sunflower and canola rapeseed meal and linseed meal. The diet of the control and experimental groups differed insignificantly. The diet of the control group of ewes contained 21.7 MJ of exchange energy, 187 g of digestible protein, 2.29 kg of dry matter, and in the diet of the experimental group, respectively, 22.1 MJ of exchange energy, 188 g of digestible protein and 2.26 kg of dry matter . In one kilogram of dry matter, the fodder of the sheep of the control group contained 9.5 MJ of exchange energy, and the experimental group animals – 9.8 MJ. It was found, that adjusting the level of protein and energy in the standard feed for lactating ewes in the zone of the Carpathians by introducing into it of local high-protein supplements   provides maintaining the weights for the lactation period;  increase  the average daily milk yield after suckling lambs by 23.8%;  increase the average daily growth of suckling lambs by 6.7–13.9%; physiological level of activity of alanineaminotransferase, aspartateaminotransferase and lactatedehydrogenase in blood plasma.