Enhancement of sperm motility and viability by turmeric by-product dietary supplementation in roosters

•Turmeric by-product (TBP) improves sperm properties in domestic fowl.•Dietary TBP increases sperm motility and viability under a controlled temperature.•Computer-assisted sperm analysis enabled a thorough analysis of the effects of TBP.•TBP reduced ROS generation under heat stress.•Our results indicated that TBP may effectively improve rooster fertility.

Improving sperm motility and viability are major goals to improve efficiency in the poultry industry. In this study, the effects of supplemental dietary turmeric by-product (TBP) from commercial turmeric production on sperm motility, viability, and antioxidative status were examined in domestic fowl. Mature Rhode Island Red roosters were divided into two groups - controls (group C) without TBP administration and test subjects (group T) fed a basal diet supplemented with 0.8 g of TBP/day in a temperature-controlled rearing facility (Experiment 1) and 1.6 g/day under heat stress (Experiment 2) for 4 weeks. In Experiment 1, TBP dietary supplementation increased the sperm motility variables straight-line velocity, curvilinear velocity, and linearity based on a computer-assisted semen analysis, 2 weeks following TBP supplementation. In Experiment 2, using flow cytometry, sperm viability at 3 and 4 weeks following TBP supplementation was greater in Group T than C, and this increase was consistent with a reduction in reactive oxygen species (ROS) production at 2 and 4 weeks. The results of both experiments clearly demonstrate that dietary supplementation with TBP enhanced sperm motility in the controlled-temperature conditions as well as sperm viability, and reduced ROS generation when heat stress prevailed. Considering its potential application in a range of environments, TBP may serve as an economical and potent antioxidant to improve rooster fertility.