Clinical and biochemical assessment of a probiotic feed supplement application on calves

Abstract

The intensification of animal husbandry prompts producers to use modern technologies that are safe for humans and promote the welfare and health of animals. Despite the long time spent studying the effectiveness of probiotics, questions regarding the optimal composition and period of rational use of probiotic feed additives (PFA) for young animals, in particular as alternative to the use of antibiotics remain relevant. The purpose of the study was to evaluate the effect of a probiotic feed additive on clinical and biochemical parameters in healthy calves (Black-and-white breed, 1 day to 1 year of age) from different physiological groups and preventive efficiency. The use of PFA (Bacillus subtilis and Bacillus licheniformis) at all stages of growing calves had a positive effect on growth indicators, increased live weight of animals and average daily weight gain, allowing for more efficient use of feed, mitigation of the production stress and obtaining greater profits from intensive animal breeding, sales of ecological products, and the reduction of costs for veterinary services. Thus, it is advised to feed PFA in the neonatal period for the formation of intestinal microbiocenosis; at the age of 1-2 months: in order to correct the immune reactivity; at the age of 3 months - to improve the processes of rumen formation. The PFA, additionally supplemented with Sacharomyces serevisiae, can correct the immune reactivity of 1-2 months old calves; improved the processes of rumen formation at the age of 3 months; and prepared heifers for mating at the age of 12 months. The obtained results experimentally substantiated the use of probiotics within the framework of the WHO Global Action Plan on Anti­microbial Resistance - it has been proven that the prevention of diarrhoea and/or bronchopneumonia as a result of the use of probiotics, even in one calf, allowed avoiding at least 4-6 days of antibacterial therapy that reduced the risks of formation of antibiotic-resistant bacterial clones, in particular zoonotic agents.