Results of studies of the influence of phytopreparations on cows and calfs V.S. Kozyr, P.P. Antonenko, N.I. Suslova and R.V. Mylostyvyi E3S Web Conf., 282 (2021) 04003 Published online: 05 July 2021 DOI: 10.1051/e3sconf/202128204003