Stable bull fertility protein markers in seminal plasma.

Abstract Bull fertility is an important trait in breeding as the semen of one bull can, potentially, be used to perform thousands of inseminations. The high number of inseminations needed to obtain reliable measures from Non-Return Rates to oestrus creates difficulties in assessing fertility accurately. Improving molecular knowledge of seminal properties may provide ways to facilitate selection of bulls with good semen quality. In this study, liquid chromatography mass spectrometry (LC-MS/MS) was used to analyze the protein content from the seminal plasma of 20 bulls with Non-Return Rates between 35 and 60%, sampled across three seasons. Overall, 1343 proteins were identified and proteins with consistent correlation to fertility across multiple seasons found. From these, nine protein groups had a significant Pearson correlation (p Significance The ability of bull spermatozoa to fertilize oocytes is crucial for breeding efficiency. However, the reliability of this trait from field measures is relatively low and the prediction of fertility given by conventional methods to evaluate sperm quality is currently not very accurate. In this work, we identify sets of proteins in bull seminal plasma from repeated samples collected at different times of the year that correlate to fertility in a consistent way. We combined these individual proteins to build a molecular signature predictive of fertility. This study provides an overview of proteins linked to fertility in seminal plasma, thereby increasing knowledge of the bull seminal plasma proteome. Protein signatures from the latter, potentially related to fertility, may be of use to predict fertility for individual bulls.