Effects of neonatal androgenization on growth and carcass composition in female mice

Sixty female mice were injected neonatally with testosterone propionate. This led to an increase in body weight at 56 days (P less than 0.01) and a reduction in carcass fat (P less than 0.005). Food conversion ratio from 28 to 49 days was lower in the treated group than in the controls (P less than 0.01). The data indicate that treated females can reach values similar to those of males. Histological studies revealed a lack of luteal tissue in treated females at 56 days. This effect might be due to a modification in the nervous control of ovarian activity. Growth hormone secretion was higher in treated females than in controls (P less than 0.05). These results suggest that androgenization of females to achieve the performance characteristics of intact males could have important implications in meat production.