Exogenous Progesterone for Offspring Sex Ratio Manipulation in Arabic Chickens (Gallus turcicus) Leading to Increasing Female Chicks Proportion

Abstract

Female birds of egg-laying hens are more valuable than males, because males bird have no commercial value. The opportunity to manipulate offspring sex ratio in poultry has been observed in female birds; hence, female birds have heterogametic ZW chromosomes. High progesterone concentration 2-5 h before ovulation is thought to affect the segregation of female sex chromosomes as the basis for determining the sex of offspring. This study aimed to investigate the effect of progesterone induction in Arabic hens, which was conducted 5 h before ovulation, along with the time of the first meiosis; therefore, segregation of sex chromosomes leading to an increase in female offspring. The study utilized on 60 Arabic hens divided into three treatment groups: Without injection (P₀), progesterone injection 1 mg/hen, (P₁), progesterone injection 2 mg/hen (P₂). The results showed that the percentage of female offspring at P₀ and P₁ was 54.74 and 53.33%, respectively, while P₂ hens resulted in 62.92% females, the highest female offspring rate than the other groups. Chi-square analysis of sex ratio showed that P₀ and P₁ hens had no significant effect (P>0.05) while P₂ hens being significant (P<0.05) from the expected sex ratio (50:50). Progesterone concentration of hens produced female offspring in the P₂ group was 7.15 ng/ml being highly significant (P<0.05) than that found in the hens produced male offspring (4.53 ng/ml). Progesterone 5 h preceding ovulation in the Arabic hens with a 2 mg/hen dose can increase the proportion of female offspring; therefore, an opportunity for sex ratio manipulation in Arabic chickens.