Numerous studies have shown that improvements in the sperm and semen quality of males of many species can be achieved with appropriate dietary supplements added to feed or fodder. Particularly promising seems to be the inclusion of omega polyunsaturated fatty acids in the diets of males. Among other things, it has been shown that linseed oil ethyl esters (EELO can be an excellent source of omega 3 polyunsaturated fatty acids in animal diets. These compounds are more durable and resistant to oxidation, epoxidation and resinification processes, and do not exhibit toxic properties in living organisms. At present, there is a lack of data in the literature on the enrichment of boar diets with EELO. The purpose of this study was to analyze the effects of the addition of EELO to boar diets on the properties of sperm in fresh semen. The study was conducted during the summer on semen collected from 12 boars of the line 990. Linseed oil ethyl esters were administered in each feeding at a rate of 3.0% (45 mL each) in basal diets for each boar on a daily basis for 16 weeks. Ejaculates were collected manually by the gloved-hand technique, at one-week intervals for eight-week periods, from the eighth week onwards after the start of feeding. Eight ejaculates were collected from each boar, totaling 96 samples. The addition of EELO to the diets of boars caused an increase in sperm viability (p < 0.001), semen volume (310 mL versus 216 mL, p < 0.001) and sperm concentration (331 versus 216 million per mL, p < 0.001). Furthermore, in the experimental animals, there was a decrease in the percentage of spermatozoa exhibiting DNA fragmentation. The experimental boars also showed an increase in the percentage of gametes without apoptosis and capacitation and an increase in the percentage of viable spermatozoa not showing lipid peroxidation membranes. Consequently, EELO nutritional supplementation resulted in the improved quality of the fresh semen of boars.
Keywords: boar semen; linseed oil ethyl esters; sperm quality.