Ethological and biological features of the organism of the black-and-white bulls when using natural feed additives in the dietsOksana Krasnova, Ekaterina Hardina, Sergei Hramov, Michail Kudrin and Nina KonikBIO Web Conf., 17 (2020) 00237DOI: https://doi.org/10.1051/bioconf/20201700237