A comparison of the in vitro lipogenic rates and other physiologic parameters in two strains of lean and obese chickens.

Selection for abdominal fat pad size in mature hens has yielded two divergent strains of lean and obese chickens. The females in the obese line have been shown to have a greater amount of total body lipid by six weeks of age. Liver slices from 6- and 17-week old obese chickens incorporated significantly more 3H2O into extracted fractions of total lipid and saponified fatty acids. Palmitate esterification by abdominal fat pad slices from 12-week old pullets was the same for both strains when activity was expressed per unit weight of tissue. The twofold difference in size between the lean and obese fat pads at this age, however, indicates a significantly greater degree of total esterification in the obese birds. At 6-, 12-, and 17-weeks of age, the two lines exhibited similar concentrations of plasma glucose, total protein, and triglycerides.