Effects of Reducing Endogenous Estrogen on Semen Quality in Aged Male Broiler Breeder

The semen quality of the roosters is affected by different factors. One of this factors is aging that it has an adverse effects on the reproductive performance. Manipulations to increase semen quality in aged birds will only be useful if sperm fertilizing capacity is not adversely affected. Therefore, this study was conducted to investigate the effect of reduced endogenous estrogen using aromatase inhibitor in a farm of commercial broiler breeder roosters. Letrozole (Ltz) orally fed to aged ROSS 308 breeder roosters (n= 18) that were 55 weeks of age. The birds were randomly classified into three groups (n = 6 birds per group) that received different doses of aromatase inhibitor, Ltz: 0(Ltz-0), 0.03(Ltz-0.03), 0.015(Ltz- 0.015) mg Ltz/kg body weight for short-time (3 weeks). At the end of the trial, date collected and seminal traits were evaluated. The results indicated that all of parameters except semen volume including total and forward motility, plasma membrane integrity, live sperm, sperm abnormality, MDA production and spermconcentration in collected volume were significantly affected by Ltz treatment and in the Ltz-0.03 group were greater compared control group (<.0001). Overall, these data suggest that reducing endogenous estrogens could improve several reproductive performance in aged commercial broiler breeder roosters.

Keywords:

Aromatase Inhibition , Aged Roosters , Semen Traits , Fertility