Adapting lipidomic sample processing methods for boars housed in commercial settings

Fertility prediction in commercial boars would be valuable to the swine industry as the inclusion of subfertile boars results in a loss of efficiency and negative economic consequences for the farm. Emergent technology in mass spectrometry known as multiple reaction monitoring (MRM) profiling can distinguish between different fertility phenotypes across species, making it a valuable approach for fertility biomarker discovery and has yet to be used in boars. In addition, samples for lipid analysis are processed in liquid nitrogen or dry ice and are not commonly available at commercial boar studs. Therefore, the objective of this study was to determine if lipid sample processing at room temperature using methanol could be used in samples sourced from commercial boars. We observed that room temperature sample processing did not compromise the total number of lipids detected in the boar's ejaculate using MRM profiling. Results were comparable to other studies where semen samples were frozen in liquid nitrogen and noted that boars have a distinct ejaculate lipidome (cellular fat composition) profile based on major plasma membrane lipids. These results indicate that this method of sample processing for MRM profiling can be used in commercial settings for future fertility marker discovery work.