TY JOUR TI IMPROVEMENT OF CONDITIONS FOR SETTING UP THE INDIRECT ENZYME-RELATED IMMUNOASSAY METHOD FOR DIAGNOSTICS OF BOVINE ENZOOTIC LEUKEMIA KW FLK BLV KW leukemia virus KW antigen KW antibodies KW intact sheep serum KW enzyme immunoassay JO SCIENTIFIC NOTES KAZAN BAUMAN ACADEMY OF VETERINARY MEDICINE AU Usoltsev, K.V. AU Shangaraev, R.I. AU Gorbunova, M.E. AU Akhmadeev, R.M. AU Khaertynov, K.S. PY 2026 IS 262 PB Kazan state agrarian University