Protein-synthesizing, bile-forming, urea-forming and carbohydrate functions in cows with fatty degeneration of the liver

Abstract

In dairy farms of Ukraine, where highly productive dairy cows are kept, liver lesions are often diagnosed in the postpartum period. Postmortem studies of the liver of cows that were forcibly slaughtered showed that in mostly animals were diagnosed with fatty degeneration of the liver. The main causes of fatty hepatosis were violations of the structure of rations, imbalance of feeding on essential nutrients and biologically active substances, low content of easily digestible carbohydrates and high protein content. The study was performed on cows aged 4–5 years with productivity for the previous lactation of 5.600–7.500 L of milk, in a winter-stall period of keeping, 2–3 weeks after calving. According to clinical and biochemical blood tests, two groups of cows were formed – 50 clinically healthy and 50 cows with fatty liver disease. In cows diagnosed with fatty liver degeneration, the disease was manifested by decreased productivity and fatness, loss of appetite, oppression, hypotony of the rumen, reticulum and omasum. In some cows, there was pain at the liver area, increasing boundaries of hepatic dullness, jaundice of the visible mucous membranes and sclera. The blood serum of all cows with fatty liver disease established a decrease in albumin content, indicating impaired protein synthesis function of the liver. In some cows, the content of total protein in the serum increased due to globulin fractions, mainly gamma globulins. The ratio between the content of albumins and globulins decreased, which indicates the development in the blood of sick animals dysproteinemia. The development of fatty infiltration of the liver caused an increase in the concentration of bile acids in the serum of all sick cows. This is due to reduced conjugation and excretion of cholates by affected hepatocytes from the bile capillaries. The formation, absorption, conjugation, and excretion of bilirubin in the bile is disturbed, which causes the accumulation of total and conjugated bilirubin in the serum of sick animals. The cholesterol content in the blood of cows decreased, caused a violation of the esterification of its esters by hepatocytes. The established changes in the content of bile acids, total and conjugated bilirubin, and cholesterol in the blood of sick cows indicate a violation of bile secretion, bile production, and cholestasis development. In some cows with fatty liver degeneration, urea formation function and carbohydrate function are impaired, leading to a decrease in blood urea content and glucose.