Dietary supplementation with a source of omega-3 fatty acids increases sperm number and the duration of ejaculation in boars

Development of nutritional strategies to increase the production of fertile sperm would further enhance the distribution of superior genetic material by AI. The objective was to determine the effects of a dietary source of omega-3 fatty acids in boars on semen characteristics and sexual behavior. Boars were fed daily 2.2 kg of a diet top-dressed with 0.3 kg of corn (controls; n = 12) or 0.3 kg of a supplement containing 31% omega-3 fatty acids (n = 12) for 16 weeks. Semen was collected weekly and for boars that received the supplement containing omega-3 fatty acids, total sperm per ejaculate averaged 84.3 ± 2.3 × 109 (mean ± S.E.M.) during Weeks 0–7, and increased (P = 0.02) to 95.6 ± 2.3 × 109 during Weeks 8–15. Control boars averaged 86.3 ± 2.3 × 109 sperm per ejaculate during Weeks 0–7 and 86.4 ± 2.3 × 109 during Weeks 8–15. Other semen characteristics were similar (P > 0.1) between groups. Duration of ejaculation was affected by treatment (343.9 s for controls and 388.8 s for boars fed omega-3 fatty acids; S.E.M. = 15.7; P = 0.05). In summary, semen characteristics and sexual behavior were altered in boars fed a supplement containing omega-3 fatty acids. Boar semen is typically diluted to create AI doses containing 3 × 109 sperm each; therefore, use of the supplement increased the number of potential AI doses by approximately three per ejaculate after the initial 7 week supplementation period.