Liver Steatosis Following Supplementation with Fat in Dairy Cow Diets

Abstract

Lubojacka V., A. Pechova, R. Dvofiak, P. Drastich, V. Kummer, J. Poul: Liver Steatosis Following Supplementation with Fat in Dairy Cow Diets. Acta Vet Brno 2005, 74: 217224. The aim of the present investigation was to determine the influence of increased intake of fats (calciferous salts of fatty acids) in the early lactation period on the development of liver steatosis. Twenty dairy cows in the study were divided into an experimental group (E; n = 10) and a control group (C; n = 10). Balanced diets of energy content, crude protein and minerals (except calcium) were fed to the two groups of dairy cows. The differences were in the fat content (3.7% and 6.99% dietary dry matter in the control and experimental groups, respectively), fibre (14.4% and 15.6% dietary dry matter in the control and experimental groups, respectively) and calcium (0.83% and 1.3% dietary dry matter in the control and experimental groups, respectively). The source of fats in the diet fed to the experimental group was treated rape cake (calciferous salts of fatty acids). The two diets were introduced on the day of calving. Blood samples were collected in weeks 2 and 4 post partum, and liver biopsies were performed in week 4 post partum. The histological examination of liver samples showed a significantly higher lipid infiltration (69.03 ± 8.42 vs. 23.83 ± 5.16%; p < 0.01) and significantly lower liver glycogen concentrations (25.74 ± 2.74% vs. 53.15 ± 1.74%; p < 0.01). Two weeks post partum, the experimental group had significantly higher blood serum concentrations of betahydroxybutyrate - BHB (1.04 ± 0.58 vs. 0.54 ± 0.18 mmol·l-1; p < 0.05), non-esterified fatty acids - NEFA (0.96 ± 0.57 vs. 0.39 ± 0.24 mmol·l -1 ; p < 0.05), total cholesterol (3.54 ± 1.29 vs. 2.51 ± 0.44 mmol·l -1 ; p < 0.05), total bilirubin (8.61 ± 3.73 vs. 5.29 ± 1.07 µmol·l-1; p < 0.05), lactate dehydrogenase - LDH (49.79 ± 12.43 vs. 37.20 ± 5.48 µkat·l -1 ; p < 0.05), significantly lower concentrations of total protein (78.77 ± 5.01 vs. 88.72 ± 7.05 g·l -1 ; p < 0.01) and urea (4.09 ± 0.92 vs. 4.99 ± 0.61 mmol·l -1 ; p < 0.05). In week 4 post partum, the experimental group had significantly higher concentrations of NEFA (0.62 ± 0.48 vs. 0.25 ± 0.1 mmol·l -1 ; p < 0.05), total cholesterol (4.70 ± 0.77 vs. 3.03 ± 0.49 mmol·l -1 ; p < 0.01), LDH (45.97 ± 10.70 vs. 36.14 ± 3.97 µkat·l -1 ; p < 0.05) and significantly lower concentration of urea (4.43 ± 1.01 vs. 5.88 ± 1.08 mmol·l -1 ; p < 0.01). Our investigations suggest that increased intake of fats (6.99% dietary dry matter) in the early lactation period has a substantial effect on the development of liver steatosis. Fatty liver, liver biopsy, blood, glycogen, triacylglycerol