For citations:

Chechenikhina O.S., Kazantseva E.S., Stepanova I.A., Smirnov M.N. PRODUCTIVE LONGEVITY OF BLACK-AND-WHITE COWS IN DIFFERENT ECOLOGICAL AREAS OF THE URAL ZONE. Bulletin of NSAU (Novosibirsk State Agrarian University). 2019;(3):120-126. (In Russ.) https://doi.org/10.31677/2072-6724-2019-52-3-120-126