An association between progressive motility (PM) and spermatozoa fertility competence has been suggested. However, the mechanism that underlies PM is not clear enough. We examined physiological characteristics and fatty acid composition of fresh spermatozoa with high and low PM. Additional analysis of fatty acid composition and structural characteristics was performed on spermatozoa samples with high and low progressively motile spermatozoa’s survival (PMSS), i.e., the ratio between the proportion of progressively motile spermatozoa after and before cryopreservation. Finally, a fertility field trial was conducted to examine the association between the number of PM spermatozoa within the insemination straw post thawing and conception rate. Analysis of fresh spermatozoa revealed a higher omega-6 to omega-3 ratio in ejaculates with low PM relative to those with high PM (p < 0.01). The proportion of polyunsaturated fatty acids was higher in low-PMSS fresh samples (p < 0.05) relative to their high-PMSS counterparts. Fresh samples with high-PMSS expressed a higher mitochondrial membrane potential (p < 0.05) and a higher proportion of viable cells that expressed reactive oxygen species (ROS; p < 0.05). Post-thawing evaluation revealed a reduced proportion of progressively motile sperm, with a prominent effect in samples with high PM relative to low PM, defined before freezing (p < 0.01). No differences in spermatozoa mitochondrial membrane potential or ROS level were found post-thawing. A fertility study revealed a positive correlation between the number of progressively motile spermatozoa within a standard insemination straw and conception rate (p < 0.05). Considering these, the bull PMSS is suggested to be taken into account at the time of straw preparation.

The proportion of spermatozoa with progressive motility is widely used to evaluate the quality of a single ejaculate. However, the cellular and physiological mechanisms underlying this trait remain unclear. The present study examined the association between the progressive motility of bovine spermatozoa, their quality and their fertilization competence in vitro, and subsequently the association with the developmental morphokinetics of the formed embryos. Fresh ejaculates were classified and divided into groups with high (HPM), medium (MPM), or low (LPM) progressive motility. Then, spermatozoa were evaluated for their morphology, plasma membrane integrity, mitochondrial membrane potential, oxidative status, and acrosome integrity. The findings revealed that spermatozoa from HPM ejaculates enhanced motility in association with higher mitochondrial membrane potential relative to the LPM group, suggesting higher metabolic potential. No differences were recorded in fertilization competence among groups; however, the developmental kinetics of the formed embryos, determined by a time-lapse system, differed; embryos derived from HPM spermatozoa cleaved earlier to the two-, three-, and four-cell stages than embryos derived from MPM spermatozoa, suggesting that HPM-derived embryos are of good quality. Our findings suggest that progressive motility is not only a motility characteristic; it also reflects cellular quality of spermatozoa and the formed embryo.