Kropyvka, Y., Bomko, V., & Kropyvka, S. (2021). The economic efficiency of the use of mixed ligand complexes of Zinc, Manganese and Cobalt in the rations of highlyproductive cows of the Ukrain-ian Red-Spotted Dairy breed. Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies. Series: Agricultural Sciences, 23(95), 82-86. https://doi.org/10.32718/nvlvet-a9512