Evaluation of the efficiency of using a preparation of humic nature as a feed ad-ditive in the diet of dairy cows of the holshtin breed

Abstract

Among a significant number of biologically active substances capable of increasing the level of nonspecific resistance, our attention was drawn to humic substances that positively affect the physiological and biochemical status of animals. The effect of biologically active substances, which includes potassium humate, is evaluated, which makes it possible to activate the metabolic processes in the animal's body, to promote the transformation of feed nutrients into available forms, and thereby play an essential role in solving one of the primary tasks – the rational use of feed. The effect of potassium humate in a dose of 4 g of the drug per 1 cow during the dry period per day was determined, contributing to an increase in the live weight of newborn calves by 22.4 %. Later, the calves of the experimental group exceeded the control group: after the 1st month of growing – by 28%, and after the 2nd month – by 23.9 %. Due to the feeding of potassium humate, the number of fertilized cows increased by 22 % compared to the control. The pattern of enrichment of rations with potassium humate is characterized, which allows an increase in cows' average daily milk yield by 20 % with a simultaneous reduction in protein consumption by 14.2 %, feed units by 13.9 %, and exchangeable energy by 13.5 %. The use of potassium humate in the diets of dry cows does not cause significant changes in protein metabolism and the levels of AST, ALT, and glucose, which is evidence of normal liver function, but it helps. Reduced cholesterol synthesis in cows that consumed potassium humate – up to 3.88 mmol/l against 4.72 in the control. The explanation of this phenomenon will require further research. It was possible to increase the overall efficiency of nutrition by 10–20 % during the experiment, thanks to the inclusion of potassium humate in the feed mixtures of nettles and dairy cows. The adaptogenic effect of humic preparations has also been proven, including in stressful situations.