Adipose Cellularity Studies in Commercial Broiler Chicks

The development of adipose depots in broiler chickens prior to sexual maturity occurred as a consequence of both adipocyte hyperplasia and hypertrophy. Prior to about 28 days of age, increases in fat deposition were primarily associated with differences in adipocyte number while at later ages adipocyte hypertrophy became the primary influence. The feeding of diets containing a low calorie-to-protein ratio reduced fat deposition by decreasing adipocyte hypertrophy. The differences in adiposity between two commercial broiler stocks were due primarily to differences in adipocyte number prior to 28 days of age. Results at older ages were inconclusive for differences among populations.