Abstract Prediction of bull fertility is critical for the sustainability of both dairy and beef cattle production. Even though bulls produce ample amounts of sperm with normal parameters, some bulls may still suffer from subpar fertility. This causes major economic losses in the cattle industry because using artificial insemination, semen from one single bull can be used to inseminate hundreds of thousands of cows. Although there are several traditional methods to estimate bull fertility, such methods are not sufficient to explain and accurately predict the subfertility of individual bulls. Since fertility is a complex trait influenced by a number of factors including genetics, epigenetics, and environment, there is an urgent need for a comprehensive methodological approach to clarify uncertainty in male subfertility. The present review focuses on molecular and functional signatures of bull sperm associated with fertility. Potential roles of functional genomics (proteome, small noncoding RNAs, lipidome, metabolome) on determining male fertility and its potential as a fertility biomarker are discussed. This review provides a better understanding of the molecular signatures of viable and fertile sperm cells and their potential to be used as fertility biomarkers. This information will help uncover the underlying reasons for idiopathic subfertility.

ABSTRACT The objective of the present study was to develop a methodology to obtain the enriched fraction of ram seminal vesicle protein 14 (RSVP14). The study was developed using Morada Nova rams, from which semen samples were collected weekly. Seminal plasma proteins were precipitated with cold ethanol, and then 6.15 mg/mL of total proteins were subjected to liquid gelatin affinity chromatography using a Gelatin-Sepharose matrix coupled to an automated chromatographic system. Proteins were eluted into four fractions (A, B, C, and D), in which A and B contained non-gelatin-binding proteins, and C and D fractions contained gelatin-binding proteins. Gels were analyzed by Quantity One software, in which five protein bands were detected in fraction D, with molecular weights between 12 and 30 kDa. The gelatin-binding proteins (fraction D) were loaded into a HiTrap™ Heparin HP affinity column. Two chromatographic fractions were separated (D1 and D2), in which D1 contained non-heparin-binding proteins, and D2 contained heparin-binding proteins. Proteins from the last two peaks were subjected to 12.5% SDS-PAGE and Western Blot. Two bands with molecular weight of 14 and 24 kDa, contained in fraction D1, were excised from gel and subjected to tandem mass spectrometry, identifying the proteins RSVP14 and RSVP24. Thus, the chromatographic methods of the present study are efficient to capture the enriched fraction of RSVP14.