Aim: Ethylene glycol (EG) has been employed as a cryoprotectant for many years in mammalian semen cryopreservation but not assessed for birds except for its recently illustrated beneficial effects on commercial chicken lines. The Indian red jungle fowl is facing trouble in its native range due to human encroachment. Therefore, the present study was designed to elucidate the cryoprotective effect of different EG concentrations (5%, 10%, 15%, and 20%) on frozen Indian red jungle fowl semen. Materials and Methods: Semen was collected from 20 cocks, and qualifying ejaculates (>70% motility) were pooled and diluted (15) with red fowl extender. EG was added to the four samples and 20% glycerol in control at 4°C. Samples were equilibrated and cryopreserved in LN2. Semen quality and biochemical activity were assessed at various stages of cryopreservation. Results: Sperm motility, viability, plasma membrane and acrosomal integrity, chromatin integrity, and mitochondrial activity were recorded highest (p < 0.05) with 20% EG at the post-equilibration and post-thaw stages. Lipid peroxidation was recorded lowest (p < 0.05) with 20% EG compared with other concentrations and control at the post-equilibration and post-thaw stages. Conclusions: It is concluded that 20% EG exhibits cryoprotective properties in terms of regulating morphological and biochemical traits of frozen Indian red jungle fowl sperm.
Keywords: avian; cryopreservation; ethylene glycol; semen.