EVALUATION OF THE LEVELS OF LEPTIN, BETA HYDROXYL BUTYRATE, GLUCOSE, CHOLESTEROL AND TRIGLYCERIDE IN SERUM OF HOLSTEIN COWS WITH SUB CLINICAL KETOSIS

Leptin hormone is secreted from the white adipocytes of adipose tissue and its levels increase with the increase in size of the adipose tissue.  One of the most important actions of this hormone is the regulation of body metabolism by consuming adipose tissue and production of energy. The objective of this study was determination of Leptin and BHB, glucose, cholesterol and triglyceride levels in healthy Holstein cows and cows with Sub clinical Ketosis and the determination of the prevalence of Sub clinical Ketosis, using BHB level in blood serum as the gold standard. In this survey 7 dairy farms were chosen in Shahriar, (Tehran province), Samples were taken from 100 cows at two periods: 1) last week of pregnancy (dry period), 2) The same cows at 2 months after parturition. Serum samples were harvested and leptin levels were measured using DBC ELISA kit,Canada, BHB levels  were measured using  RANBUT kits and glucose, cholesterol and triglyceride levels were measured by commercial  kits (ziest chem) and spectrophotometer. In this study, the prevalence of Sub clinical Ketosis, using the 1/2, 1/4, 1/7 mmol BHB, as the cut point was calculated as 18%, 14% and 4% respectively. Leptin levels decreased significantly after parturition in healthy cows and those affected by subclinical ketosis. There was a significant correlation between leptin and glucose (r=0.53) and BHB and glucose (r= -0.27) in pre parturient group of cows. In the group of cows 2 month after parturition, there was a significant correlation between leptin and glucose (r=0.65), BHB and triglyceride (r=0.97) and BHB and glucose (r= -0.64). In the group affected by subclinical ketosis, a significant correlation was observed between leptin and glucose (r=0.72), BHB and glucose (r=-0.38), BHB and triglyceride (r=0.85) and BHB and cholesterol (r=0.64).