Formation of local protection of the respiratory tract in Holstein calves

Abstract

The processes of formation of the local protection of the respiratory tract in nasal secretion samples of Holstein calves frombirth to 6 months of age that were born from clinically healthy cows were examined. Only clinically healthy animals were involvedin the experiment. Nasal secretion samples were collected with the help of a sterile foam tampon with a fixing thread in order toassess local immunity in animals at the age of 1, 5, 10, 30, 60, 90, 120, 150, and 180 days. Total protein, mucin, lysozyme activity, andalkaline phosphatase (ALP) were determined using commercially available methods. The amounts of immunoglobulins were studiedusing disk electrophoresis in polyacrylamide gel with commercial marker proteins. Studies have shown that the primary potential oflocal protection of the respiratory tract is formed during intrauterine development. The main factors of primary potential are mucin,lysozyme, alkaline phosphatase, and secretory immunoglobulins of classes A (SIgA) and M (SIgM), which provide safety of adaptationin newborns to the new conditions of existence. There is a decrease in mucin level by 47.3% (P < 0.001), in SIgA by a factor of 6.7 (P 0.05) at the age of 60 days and mucinlevel increases by 56.7% (P < 0.001) between 2 and 6 months