Effect of Exposure to Seminal Plasma Through Natural Mating in Cattle on Conceptus Length and Gene Expression

Abstract

A growing body of evidence suggests that paternal factors have an impact on offspring development. These studies have been mainly carried out in mice, where seminal plasma (SP) has been shown to regulate endometrial gene expression and impact embryo development and subsequent offspring health. In cattle, infusion of SP into the uterus also induces changes in endometrial gene expression, however, evidence for an effect of SP on early embryo development is lacking. In addition, during natural mating, the bull ejaculates in the vagina; hence, it is not clear whether any SP reaches the uterus in this species. Thus, the aim of the present study was to determine whether SP exposure leads to improved early embryo survival and developmental rates in cattle. To this end, Day 7 in vitro produced blastocysts were transferred to heifers (12-15 per heifer) previously mated to vasectomized bulls (n = 13 heifers) or left unmated (n = 12 heifers; control). At Day 14, heifers were slaughtered, and conceptuses were recovered to assess size, morphology and expression of candidate genes involved in different developmental pathways. Additionally, CL volume at Day 7, and weight and volume of CL at Day 14 were recorded. No effect of SP on CL volume and weight not on conceptus recovery rate was observed. However, filamentous conceptuses recovered from SP-exposed heifers were longer in comparison to the control group and differed in expression of CALM1, CITED1, DLD, HNRNPDL, PTGS2, and TGFB3. In conclusion, data indicate that female exposure to SP during natural mating can affect conceptus development in cattle. This is probably achieved through modulation of the female reproductive environment at the time of mating.

Mating to Intact, but Not Vasectomized, Males Elicits Changes in the Endometrial Transcriptome: Insights From the Bovine Model

“…Indeed, recently it has been shown that infusion of SP into the vagina, but not into the uterus, modifies endometrial levels of epidermal growth factor (Badrakh et al, 2020), which highlights the importance of considering the ejaculate deposition site in natural conception in these studies. We recently reported a modest increase in conceptus length in embryos that developed from Day 7 to Day 14 in the uterus of heifers mated to a vasectomized bull in comparison to unmated heifers (Mateo-Otero et al, 2020). However, exposure of heifers to vasectomized bulls prior to AI failed to increase pregnancy rates (Pfeiffer et al, 2012).…”

Preimplantation Endometrial Transcriptomics in Natural Conception Cycle of the Rhesus Monkey

“…A plausible explanation for the observed differentiation towards immunotolerance in the secretory phase endometrium of mated and proven fecund group of animals could be due to the presence of seminal plasma inducing the observed genomic expression. In fact, evidence based on a series of elegant experiments is now available across various mammalian species to indicate that seminal plasma exerts substantial modifying action on endometrium towards receptivity, ovo-implantation, immunotolerance, embryo development, and establishment of pregnancy [38,52,[57][58][59][60][61][62]. To our knowledge, this is the first report supporting the notion that seminal plasma could induce at the genomic expression level a process bias for immunotolerance to non-self antigens in the secretory phase endometrium of natural conception cycle in the rhesus macaque.…”

Sperm exposure to accessory gland secretions alters the transcriptomic response of the endometrium in cattle

“…In fact, SP infusion into the vagina, but not into the uterus, can modify endometrial epidermal growth factor concentrations in repeat breeder cows 31 . We recently reported a modest increase in Day 14 conceptus length following transfer of bovine embryos on Day 7 into the uterus of heifers mated to a vasectomized bull in comparison to unmated heifers 32 . In addition, data from our group have shown that mating to intact or vasectomised bulls induces a higher expression of interleukin 1 A (IL1A) and tumor necrosis factor alpha (TNFA) in the vagina than in the oviduct, whereas this difference is not observed in unmated heifers 33 .…”