Evaluation of semen quality in roosters of different age during hot climatic condition.

The present experiment was conducted to evaluate the semen quality of roosters of different ages during hot climatic condition. Semen from roosters (n=8/age group) of 23, 42 and 65 weeks of age was collected and evaluated for different physical parameters. The sperm membrane integrity was evaluated by hypo-osmotic swelling test, whereas sperm DNA fragmentation was assessed by Sperm Chromatin Dispersion (SCD) test. The seminal plasma cortisol level was assessed by EIA. The shed average Temperature Humidity Index (THI) during the experiment period was 79.32. Semen volume and sperm DNA fragmentation were significantly different (P≤0.05) between the age groups tested. Roosters of 42 weeks age had higher semen volume and lower sperm DNA fragmentation during study period. None of the other parameters were influenced by the age of the birds. The results indicated that semen quality was affected by the age of the birds. The extreme heat condition also appears to exert a negative influence on the sperm chromatin in roosters.