Hypoglycemia and reduced feed intake in broiler chickens treated with metformin

The bi-guanide metformin is used to treat noninsulin dependent diabetes in obese patients. In addition to having antihyperglycemic effects, metformin is also anorectic and reduces BW. These studies were performed to determine if metformin possesses similar properties in chickens. Metformin-HCl was administered to 14-day-old broiler chickens at either 300 or 600 mg/kg per day in the drinking water for 10 d while monitoring BW and feed intake. No changes in water intake were observed, while feed intake and daily gains were only significantly reduced by the 600 mg/kg dose. After oral administration of a single dose of 300 mg/kg metformin-HCl, feed intake was significantly reduced by 4 h and remained suppressed for greater than 24 h relative to controls. Plasma hormones and metabolites (glucose, lactate, insulin, glucagon, uric acid, nonesterified fatty acid, and triglycerides) were monitored at 1, 2, 3, 6, and 24 h posttreatment. Significant and acute decreases in blood glucose, insulin, and triglycerides were observed at 3 h posttreatment as compared to controls. Opposing acute increases in glucagon and NEFA levels were also observed at 3 h followed by an increase in uric add 6 h posttreatment. These observations suggest that metformin induces metabolic changes in birds, similar to that observed in mammals and may act in a common manner. Metformin-HCl may be useful in glucose metabolism studies by inducing hypoglycemia, a condition rarely observed in birds.