Inflammatory diseases of the respiratory and gastrointestinal tracts are the actual problem of veterinary medicine. Innate or natural immunity plays the leading role in the initial reactions to microbial agents contaminating sterile mucous membranes of newborn animals. It is implemented through the activation of cellular and humoral factors of nonspecific resistance. Leukocyte concentration, leukogram, content of cationic proteins in neutrophils, blood serum lysozyme activity (BSLA) were studied in 20 red-motley calves in 1 hour after their birth on the days 2, 5-7 and 14-15 of life, together with an impact of these indices on the terms of appearance and clinical course of inflammatory diseases of the respiratory and gastrointestinal tracts, under conditions of a large dairy complex environment (Voronezhpishcheprodukt Co Ltd, Novousmansky district, Voronezh region) in 2014. Blood sampling was implemented in the morning before feeding from the jugular vein. Body temperature, pulse and respiratory rate, state of the visible mucous membranes, time of appearance and intensity of sucking reflex, the presence and nature of cough, dyspnea, nasal expiration, reaction to palpation of the larynx, trachea, intercostal spaces, the abdominal wall, percussion and auscultation of the chest were determined in calves. The markers of intestinal inflammation are soluble protein, erythrocytes (hemoglobin), leukocytes (leukocyte elastase), pH. They were identified in feces by dry-chemistry method during the same period and also selectively at the age of 1-1.5 months.