Relationship between Insulin to Glucagon Ratio and Metabolic Parameters in Primiparous and Multiparous Dairy Cows in Transitional Period

In order to investigate the relationship between insulin to glucagon ratio and metabolic factors in transitional period of dairy cows, 28 cows heifers with body condition score of 3.25 3.75 were selected. Dairy cows received close up diet, from 21 days prepartum until parturition and lactation diet according to nutritional requirements after parturition. Blood was sampled at 10 days before and 20 days after parturition. BCS was assessed again 20 days after parturition. Serum levels of insulin, glucagon, glucose, NEFA, BHBA, triglyceride, cholesterol and albumin were measured. Insulin, glucagon, insulin to glucagon ratio, cholesterol and albumin levels were not significant between pre and postpartum in primiparous and multiparous cows. Glucose, triglyceride and BCS were decreased at 20 days postpartum than 10 days before partum but NEFA and BHBA were increased in both groups. Serum levels of all parameters were not significantly different between primiparous and multiparous cows. No significant correlation between insulin to glucagon ratio and blood metabolites before and after parturition in primiparous and multiparous cows was observed. It seems that insulin to glucagon ratio decreases as a physiologic response in a transitional period for adaptation to increasing demands of glucose, but is not related to NEFA and BHBA. Therefore, although insulin to glucagon ratio decreased, supplying nutrient requirements of dairy cows can decrease negative energy balance.