Relationships Between Seminal Plasma Proteins and Boar Fertility – 1

North Carolina State University Swine Reproduction Research from 1998-2000. With regard to evaluation of male fertility, the swine industry is faced with two problems. First, at the present time, there are no accurate tests for boar fertility that can be completed within a reasonable time frame. Available microscopic and biochemical tests for semen quality are primarily indicators of sperm viability and poor estimates of fertilizational competence. These tests can be used to identify extremely infertile males, but are not sensitive enough to discriminate between fertility of boars within normal ranges of motility (> 60%) and morphology (> 70%). Individual boar performance records can be used to determine fertility of boars, but to be useful, require large numbers (> 100) of homospermic matings from sows on the same farm that are bred by a single technician – a situation that doesnt occur often in practical production situations. Second, there is significant variation in fertility among boars that appear to have a normal complement of spermatozoa. In other species, protein markers are present in seminal plasma that exhibit either a strong positive or negative relationship with male fertility. The relationship between these proteins and fertility has been examined most extensively in dairy bulls. In dairy bulls, there are proteins that are prevalent in semen from bulls of above average fertility and different proteins that are abundant in seminal fluids from bulls of below average fertility. Boars also exhibit unique, individual differences in the profile of their seminal plasma proteins. Whether or not these proteins can be used as an estimate of the fertility of boar semen is not known and the rationale for pursuing the present study.