عنوان مقاله [English]
Objective: Assessment of liver functions in adult Holstein cows during transition period in a dairy farm.
Design: Descriptive survey.
Animals: Six multiparous Holstein cows (2-6 calvings) Procedure: Six multiparous Holstein cows were studied from 3 weeks pre-partum to 2 weeks post-partum (beginning to end of pre- and post-partum transition periods). During the last 3 weeks of gestation the cows were fed a diet according to the conditions of pre-partum transition period. During the first 2 weeks post-partum the forage portion of the diet was offered ad libitum according to the diet which was to be fed after week 3, but the concentrate portion was increased one kg per day. The post parturient diet had less protein concentration and more fiber concentration than the recommended values. Blood samples were obtained 2 times during pre-partum and 2 times during post-partum weeks. To assess liver functions during periparturient transition period, the concentrations of glucose, total protein, albumin, globulins (?, ?, and ‘y), blood urea nitrogen, ceruloplasmin, cholesterol, triglycerides, total lipids, lipoproteins (HDL cholesterol, LDL-cholesterol, and VLDL-cholesterol), and the activity of AST and arginase were measured in sera. Statistical analysis: The results were compared between preand post-parturient transition periods using paired t test. Results: Among the biochemical parameters pertaining to liver functions, only glucose, cholesterol and LDL cholesterol showed significant difference (P<0.05) between pre- and post-partum transition periods. The concentration of glucose was lower and those of cholesterol and LDL cholesterol were higher during post-partum transition period. Conclusion: It appears that under manage mental conditions of dairy farms in the area in which the study was conducted, it is possible to provide rations suitable for transition period and to maintain good liver functions. J.Fac.Vet.Med. Univ. Tehran. 60,2:181-186,2005.