Stress and Dietary Factors Modify Boar Sperm for Processing

• Published in: Reproduction in domestic animals 2011-09, Vol.46 (s2), p.39-44
• Main Authors: Radomil, L, Pettitt, MJ, Merkies, KM, Hickey, KD, Buhr, MM
• Format: Article
• Language: English
• Subjects: Animals; artificial insemination; Artificial intelligence; boars; Body fluids; Breeding of animals; diet; Diet - veterinary; fatty acids; Hogs; hydrogen peroxide; ice; Insemination, Artificial - veterinary; lipid peroxidation; Male; membrane fluidity; mitogen-activated protein kinase; phosphorylation; semen; Semen Preservation - methods; Semen Preservation - veterinary; spermatozoa; Spermatozoa - physiology; Stress, Physiological; Swine - physiology; tyrosine; viability; vitamin E
• ISSN: 0936-6768; 1439-0531
• DOI: 10.1111/j.1439-0531.2011.01865.x

This paper reviews stresses boar sperm undergo during processing and presents preliminary results of dietary modification that minimize this damage. Processing for artificial insemination (AI) stresses boar sperm by osmotic effects; altering cell size, shape and membranes; intracellular ice formation; and production of reactive oxygen species (ROS). Sperm response to ROS is concentration‐dependent, with low levels activating the ERK pathway to stimulate tyrosine phosphorylation (Tyr‐P) and capacitation, but high concentrations or inappropriately timed onset of ROS pathways can harm sperm. Fresh boar sperm exposed to ROS increased intracellular hydrogen peroxide (H2O2) phospholipase and lipid peroxidation, maintained viability but lost motility and underwent acrosome reactions (AR). Direct incorporation of lipids ± the antioxidant Vitamin E improves the survival of liquid‐ and frozen‐stored semen. Boars fed dietary flaxseed for 8 weeks to increase n‐3 fatty acids displayed improved sperm morphology (p