Hereditary obesity and hormone deficiencies in yellow dwarf mice

Daily injection of 0.05 USPU of ovine growth hormone had no effect on greater fat deposition in yellow dwarf ( Ayadwdw) mice of either sex as compared with nonyellow dwarf mice ( aadwdw). No differences between the accelerated growth rates of both genotypes during the injection period were noted nor were there any marked differences in the increase in tail length between the genotypes. Yellow dwarf mice continued gaining weight more rapidly than nonyellow dwarf mice after the end of the injection period. Analysis of the fat and water content of the carcasses indicates that the greater rate of weight gain of yellow dwarf mice is due almost entirely to increased fat deposition. The results of this experiment suggest that the obesity of yellow mice is not due to deficiencies of growth hormone or thyrotrophin.