TY JOUR TI OPPORTUNISTIC INFECTIONS IN ANIMALS: SPREAD CAUSES AND PREVENTIVE MEASURES KW opportunistic infections KW antimicrobial drugs KW antibiotic resistance KW immunomodulators KW vaccination KW factory farming JO Bulletin of KSAU AU Gerunov, T.V. AU Gerunova, L.K. AU Pleshakova, V.I. AU Konev, A.V. PY 2022 IS 0 PB Krasnoyarsk State Agrarian University