Testicular and epididymal sperm reserve evaluations in three Jordanian goat breeds

The study aimed to determine the effect of goat breed (Shami, Mountain Black and Hybrid) on testicular and epididymal sperm reserves. The study was conducted at Mutah University Animal Farm, Jordan in March 2016. The study area lies between Latitude of 31 degrees 27 N, Longitude of 35 degrees 74 W, and an altitude of 960m. Average temperature and relative humidity recorded during the study were 14.6 degrees C and 59.0%, respectively. Hybrid had the heaviest (P=0.04) right tail epididymal weight (6.36 +/- 0.3g), the highest (P=0.03) epididymosomatic index (0.60 +/- 0.1g/kg), and the widest (P=0.02) testicular width (0.32 +/- 0.03cm/kg) relative to body weight. Epididymal sperm concentrations in the right testicular side were the highest (P=0.04) in Hybrid (0.530 +/- 0.15x10(9) sperm/ml) compared to Shami (0.386 +/- 0.04x10(9) sperm/ml) and Mountain Black (0.322 +/- 0.10x10(9) sperm/ml). Total testicular-epididymal sperm concentrations in both testes were the highest (P=0.04) in Hybrid (0.810 +/- 0.20x10 sperm/ml) compared to Shami (0.764 +/- 0.09x10(9) sperm/ml) and Mountain Black (0.716 +/- 0.12x10(9) sperm/ml). Furthermore, Hybrid had the highest (P=0.05) epididymal body sperm concentrations (0.252 +/- 0.05x10(9) sperm/ml) in both testes compared to Mountain Black and Shami. Taken together, the outcomes of this work highlighted the testicular and epididymal sperm traits in bucks of three breeds native to the semiarid region of Jordan. Hybrid displayed greater testicular traits than Shami and Mountain Black.