Efficiency of using larch bark extract as a feed additive for calves

Abstract

Relevance. In recent years, the search and synthesis of new more effective plant extracts have been intensively conducted, which also require extensive scientific and industrial tests. These include the search for local resources and the simplest methods of biotechnology and harvesting plant extracts, including feed additives. In this regard, the study of the use of a plant extract based on larch bark is of great importance and is an urgent area of research. The aim of the work is to determine the effectiveness of the use of larch bark extract as a feed additive to increase the natural resistance and intensity of growth of live weight of cattle calves.Methods. For the study, we used: larch bark extract and raido remedy in a dosage of 5 g per calfʼs head for 10 days. Hematological studies were carried out on a Beckman Coulter LH-500 analyzer using the Culture method. The activity of blood serum was determined by the methods of V.G. Dorofeichuk, O.V. Smirnova and G.A. Kuzmina.Results. Studies have found that in order to stimulate the intensity of growth of live weight of cattle in the early dairy period of cultivation, it is recommended to use a plant extract from the bark of larch, which allows to increase the intensity of growth and get an additional increase in live weight by 9.0% compared with calves of the control group. The use of the extract stimulates the formation of nonspecific resistance, which is manifested in an increase in phagocytic (by 8.5%), bactericidal (by 8.9%), lysozyme (by 6.6%) activity of the blood serum of calves compared with the control group