title: Response of insulin, glucagon, and growth hormone to intravenous glucose challenge in cows fed high fat diets.
abstract: Effect of feeding high fat diets on peripheral plasma concentrations of immunoreactive insulin, glucagon, and growth hormone following intravenous glucose challenge (100 mg D-glucose/kg body weight) at 50 and 100 d of lactation in 16 multiparous Holstein cows was evaluated. The high fat diet contained 18.5% whole cottonseed on a dry matter basis as the source of extra dietary fat. Feeding the high fat diet had no apparent effect on energy balance. Basal plasma insulin and insulin:glucagon ratio were increased in cows fed the high fat diet relative to those of controls. Glucagon, insulin, and insulin:glucagon ratio response to glucose challenge were not affected by diet. Response of growth hormone to glucose challenge at 50 d of lactation was depressed in cows fed the high fat diet. Plasma glucose peaked at greater concentrations in cows fed the high fat diet. Feeding a high fat diet to dairy cows appears to increase basal insulin concentration and insulin:glucagon ratio, which has actions opposed to glucose synthesis. Thus, endocrine effects of a high fat diet appear to favor decreased milk production.
mesh_terms: D000818:Animals; D002417:Cattle / Q000097:blood*; D003369:Cottonseed Oil / Q000494:pharmacology; D004041:Dietary Fats / Q000494:pharmacology*; D005260:Female; D005934:Glucagon / Q000097:blood*; D005947:Glucose / Q000494:pharmacology*; D013006:Growth Hormone / Q000097:blood*; D007328:Insulin / Q000097:blood*; D007774:Lactation / Q000187:drug effects; D011247:Pregnancy
chemical_list: D003369:Cottonseed Oil; D004041:Dietary Fats; D007328:Insulin; D013006:Growth Hormone; D005934:Glucagon; D005947:Glucose