Prediction of male fertility using capacitation-associated proteins in spermatozoa

Infertility and subfertility account for huge economic losses in the animal industry; indeed, 50% of animal breeding failure is associated with male infertility. Approximately 70% of cattle and 90% of pig livestock are currently produced by artificial insemination. Therefore, breeding-male selection is extremely important for the genetic benefits of progeny. Although conventional semen analysis provides an initial measure of male fertility, its clinical value is questionable. Proteomics approaches recently identified candidate protein markers in spermatozoa for evaluating male fertility. Fertility-related proteins in capacitated boar spermatozoa were shown to predict boar fertility more precisely then those detected in ejaculated spermatozoa, which motivated the development of more accurate and sensitive tools for the assessment of male fertility in relation to sperm function and fertilization. Although protein markers in spermatozoa are capable of discriminating fertile and infertile males, clinical trials are required to validate their predictive utility. This review outlines recent findings regarding the capacitation-related proteome of spermatozoa, and discusses how these proteins may be utilized to better understand the fertility of domestic animals.