bta-let-7a: Bta-let-7a is a microRNA (miRNA) that has been detected in extracellular vesicles (EVs) from ovarian follicles (OF) and uterine fluid (UF) samples [PMC9594899]. It is one of the miRNAs that have been associated with implantation in mice [PMC9594899]. Bta-let-7a is conserved in many species and has a high number of reads, with approximately 2.3 million reads [PMC4783934]. In Holstein cattle, bta-let-7a is one of the most abundant miRNAs, along with bta-miR-143, bta-let-7f, bta-let-7c, bta-miR-10b, bta-miR26a, and bta-miR29a [PMC5410099]. In the ovary, these same miRNAs are also highly abundant [PMC3164151]. In the testis, bta-miR143 and bta-miR378 are dominantly expressed miRNAs along with bta-miR1 and other let-family members such as let7f and let7b [PMC3164151]. The expression of the 3p arm of bta-let7a in dominant follicles was 27 reads while it was 34 reads in subordinate follicles [PMC4438052].