BIOCHEMICAL BLOOD PARAMETERS OF PREGNANT COWS INFECTED WITH BLV

The aim of the study is to investigate metabolic disorders in pregnant cows infected with bovine leukosis virus (BLV) and to determine their relationship with lymphocytic leukocytosis. The object of the study was the blood of BLV-infected cows (n = 8) and leukemia-free (n = 5) pregnant cows (2–9 years old, gestation period 2–7 months) of dairy productivity from a livestock farm in the Amur Region. In BLV-infected cows, the number of leukocytes ((17.2 ± 2.66) ∙ 109/l) and lymphocytes ((10.5 ± 2.88) ∙ 109/l) exceeded normal physiological parameters. Protein metabolism was characterized by low albumin levels ((26.8 ± 2.57) %) and high beta-globulin levels ((31.2 ± 1.12) %). Hypoalbuminemia and a sharp selective increase in beta-globulin levels are characteristic of beta-globulin plasmacytomas. There was a positive relationship between the lymphocyte count and beta-globulin levels (r = 0.1, p < 0.001). Mineral metabolism was characterized by low calcium levels ((2.1 ± 0.10) mmol/l), magnesium ((0.6 ± 0.05) mmol/l) and high phosphorus levels ((3.1 ± 0.21) mmol/l). Phosphorus concentration was associated with the number of leukocytes (r = 0.2, p < 0.001), lymphocytes (r = 0.3, p < 0.05). Calcium concentration was associated with the number of leukocytes (r = –0.1, p < 0.001) and lymphocytes (r = –0.1, p < 0.05). Carbohydrate metabolism was characterized by hypoglycemia ((0.4 ± 0.04) mmol/l) and a relationship with the number of leukocytes (r = –0.4, p < 0.001) and lymphocytes (r = –0.1, p < 0.01), which confirmed the increased use of glucose by the leukemic process. The level of alanine aminotransferases (ALT) exceeded the norm and was (39.7 ± 7.02) U/l. There were positive relationships between lymphocytic leukocytosis and the level of aspartate aminotransferases (AST): AST – r = 0.2, p < 0.001; ALT – r = 0.8, p < 0.001. In pregnant cows free from BLV, the number of leukocytes ((11.4 ± 1.00) ∙ 109/l) and lymphocytes ((5.2 ± 0.80) ∙ 109/l) was within the normal range, but the level of phosphorus was increased ((2.9 ± 0.27) mmol/l) and the level of calcium was decreased ((2.2 ± 0.12) mmol/l). Increased levels of alanine aminotransferases, bilirubin, phosphorus, dysproteinemia, hypoalbuminemia, hypoglycemia, hypocalcemia characterized the metabolism of BLV-infected pregnant cows and indicated damage to hepatocytes and dystrophic liver damage.