Abstract
Immunocompetent cells in the blood, colostrum (milk) of cows and in the blood of newborn calves obtained from these animals give grounds to assert that newborn calves acquire cellular immune protection due to the intake of colostrum. With the colostrum of cows, not only nonspecific, but also specific immunocompetent cells enter the newborn’s body. The creation of colostral immunity is determined by the presence of a sufficient number of protective factors in colostrum and increased permeability of the intestinal histohematogenous barrier, which is capable of passing large immunoglobulin bodies and lymphocytes unchanged in the first 24-36 hours of life. A large number of specific immunocompetent cells found in colostrum is directly related to their increased content in the blood of these animals. The strength of the immune response depends on the preservation of immunological memory cells in the blood of revaccinated animals, some of which are represented in the pool of brucellin-reactive T-lymphocytes.