The effect of holstein bulls’kappa-casein gene genotype on the productive longevity of their female offspring in the republic of BashkortostanIdris Yumaguzin, Albina Aminova, Vladimir Kosilov and Tatiana SedykhBIO Web Conf., 36 (2021) 06007DOI: https://doi.org/10.1051/bioconf/20213606007