Abstract
1. A study was conducted to identify the specificity of insulin–glucose interactions in newly hatched broiler chicks.
2. Plasma insulin concentrations in fed chicks at one day post-hatch were lower than those at later ages and tended to increase up to d 7, while the concentrations from 1 to 7 d of age were lower than those in chickens of 10 to 28 d of age.
3. Plasma glucose concentrations were lowered for 60 min by injection of insulin at 10 and 40 µg/kg body weight (BW) in both 1- and 21-d-old chicks, showing that the hypoglycaemic effect of exogenous insulin is of larger magnitude but shorter duration in 1-d-old chicks.
4. The decrease in plasma glucose concentration at 60 min after insulin injection (10 and 40 µg/kg BW) was larger in 1- to 7-d-old chicks than in 14- to 21-d-old chickens.
5. These results indicate that newly hatched broiler chicks are under the control of specific insulin–glucose interactions characterised by low plasma insulin concentrations with high sensitivity to insulin.
Acknowledgements
The authors gratefully appreciate Dr J. McMurtry, USDA, MD, USA for providing anti-chicken insulin antiserum.