Association of antioxidant defense system with semen attributes vis a vis fertility in exotic and indigenous chicken breeds.

The present study was designed to ascertain the association of antioxidant defense system with semen attributes and fertility in RIR (Rhode Island Red), PR (Punjab Red), RIR x local cross, Aseel and Kadaknath breeds. Based on sperm attributes, roosters of each breed were divided into two group i.e. G-I (exhibiting >50% sperm attributes) and G-II (exhibiting <50% sperm attributes). Motility, viability, membrane-, acrosome-, DNA-integrity and fertility differed significantly (p < 0.05) among the breeds, representing maximum in PR roosters and least in Aseel roosters. Values of sperm attributes and fertility rate were also significantly (p < 0.05) higher in G-I compared to G-II roosters in exotic as well as indigenous breeds. MDA content differed significantly (p < 0.05) in spermatozoa of five breeds. It indicated a least oxidant stress in PR and highest in Aseel. MDA concentration was significantly (P < 0.05) higher in G-II (28.36 ± 2.40-96.0 ± 6.4) than G-I (13.65 ± 1.81-52.22 ± 6.4) roosters in all breeds. Antioxidant enzyme activity varied significantly (p < 0.05) among the breeds and groups within the breeds. Significantly (p < 0.05) higher activity of four enzymes was evident in G-II as compared to G-I roosters irrespective of the breed. A moderate to strong negative correlation was perceived among LPO, SOD, GPX, catalase, GRE and sperm attributes/fertility rate. A moderate to strong positive correlation (0.21-0.92) among LPO and antioxidant enzymes revealed that with the increase in LPO, antioxidant enzymes increase too and vice versa in all breeds. Likewise, positive correlation between sperm attributes and fertility revealed that higher sperm attributes contribute to the high fertility of roosters. This is one of the first reports on complete set of antioxidant enzymes and oxidative stress in relation to sperm attributes and fertility in different five chicken breeds. A complete antioxidant enzyme system seems to modulate the oxidative stress, sperm attributes and fertility. It may be possible to use LPO as a fertility marker to select the roosters for breeding purpose in the chicken breeds.