Effect of dietary n-3 fatty acid and rooibos (Aspalathus linearis) supplementation on semen quality, sperm fatty acids and reproductive performance of aged male broiler breeders.

The purpose of this study was to assess the effects of dietary fish oil (FO) and rooibos supplementation on semen quality, fatty acids composition and reproductive performance of aged male broiler breeders. Seventy-two 47-week-old Ross broiler breeder roosters were randomly assigned to a 2 × 3 factorial arrangements to include two FO concentrations (0% and 2%) and 3 rooibos concentrations (0%, 1.5% and 3%) for 13 weeks consecutive. The different diets affected semen parameters significantly (p < 0.05), except for the semen concentration and abnormality of the sperm. The sperm of the FO and 3% rooibos-treated group showed better motility and viability when compared to the other groups (p < 0.05). The susceptibility of semen to lipid peroxidation was increased in roosters fed the rooibos-free diets (p < 0.05), but it was reduced (p < 0.05) when the diet was supplemented with 1.5% and 3% rooibos. In addition, at 64 weeks, the highest concentration of testosterone was observed in the roosters fed a diet that included 2% FO and 3% rooibos (p < 0.05); however, the difference in testosterone levels between Week 52 and Week 64 was not significant (p > 0.05). The fertility rate of collected eggs from the FO and 3% rooibos group was higher (p < 0.05) than that of the other groups at the end of the experiment. In conclusion, dietary inclusion of FO along with rooibos improved seminal quality and reproduction performance in aged roosters.