Dietary n-3 PUFAs improve fresh and post-thaw semen quality in Holstein bulls via alteration of sperm fatty acid composition.

The goal of this study was to investigate the effect of fish oil-supplemented diet on fresh and post-thaw semen quality and sperm lipid composition in bulls. Bulls were randomly assigned to two groups (n = 6). Six bulls were used as the control group and six received the fish oil (1.2% dry matter of total diet) for 11 weeks. Semen was individually collected from each bull and frozen biweekly. Semen volume, sperm concentration, viability, progressive motility, and fatty acid profile of sperm were measured in 1st, 3rd, 5th, 7th, 9th, and 11th week of experiment. Viability, progressive motility, and fatty acid profile of post-thaw sperm were also measured in 3rd, 5th, 9th, and 11th week of experiment. Data were analyzed with using Proc GLM or MIXED (for repeated measurement data) in SAS program. The fish oil-supplemented diet increased the semen volume and sperm concentration. The fish oil-supplemented diet also altered the viability, progressive motility, and fatty acid profile of fresh and post-thaw sperm. In conclusion, feeding a fish oil-enriched diet via alteration of fatty acid profile of sperm lipid could improve in vitro quality of fresh and post-thaw sperm in Holstein bulls.