Effect of In Ovo Injection of Anastrozole on Sex Ratio and Quality of Broiler Chicks

Broiler breeders prefer male chicks because of economic benefits to female chicks.  One of the ways to achieve this goal is to manipulate sex using aromatase inhibitors. Therefore, current research was conducted to investigate the effect of in ovo injection of different levels of anastrozole (an aromatase inhibitor) on the sex ratio and quality of broiler chicks. This research was carried out with 480 eggs of Ross 308 as a completely randomized design with six treatments include, four replicates and 20 eggs per replicate. Experimental treatments include: 1. Non-injected control: with No injections 2-Control two  (Sham control(: Corn oil solvent + DMSO 3- Injection 30 μl of letrozole at a concentration of 1 mg/ml 4-anastrozole 30 μl injection at a concentration of 0.25 mg/ml 5- Injection of 30 μl anastrozole at a concentration of 0.5 mg/ml 6- Injection of 30 μL anastrozole at a concentration of 0.75 mg/ml. Hatching, sexual differentiation, chick quality, fetal mortality and economic traits were evaluated in this study. The results showed that in ovo injection anastrozole ovi-position did not have a significant effect on the sex and quality of broiler chicks. The percentage of hatching eggs in the anastrozole injection was decreased in comparison with the three control treatments, and also the mortality rate in the first incubation period was increased. In ovo injection of anastrozole compared to three treatments significantly increased carcass weight, average weight of seven days and growth rate, and a significant decrease was observed in the mean conversion factor, although it had no significant effect on the mean of initial weights. Overall, it can be concluded from the findings of this study that in ovo injection of anastrozole increased, carcass weight and weight of chicks at seven days and reduced the percentage of hatchability, but did not affect sex differentiation and quality of broiler chicks.