The ability of donkey sperm to induce oocyte activation and mule embryo development after ICSI.

Members of the Equus genus exhibit a fascinating capacity for hybridization, giving rise to healthy offspring. Mules, resulting from the mating of a mare with a jack, represent the most prevalent equid hybrid, serving diverse roles in our society. While in vitro embryo production, particularly through Intracytoplasmic Sperm Injection (ICSI), has rapidly gained significance in domestic horses, the in vitro production in other equids remains largely unexplored.

Characteristics of follicular dynamics and reproductive hormone profiles during oestrous cycles of jennies over an entire year.

Although donkeys have been domesticated for over 6,000 years, limited information is available concerning their reproductive physiology, especially under intensive rearing conditions. The aims of this experiment were to study follicular dynamics and reproductive hormone variation in jennies during the inter-ovulatory interval in different seasons. A total of 12 continuous cycles of six Dezhou Black (DB) donkey jennies were examined in four different seasons.

Practical protocols for timed artificial insemination of jennies using cooled or frozen donkey semen.

Background: With the expansion of the donkey industry, timed artificial insemination (TAI) is becoming increasingly important in the reproductive management of jennies, however, TAI has not been widely investigated in donkeys.

Objectives: To develop efficient TAI protocols for cooled or frozen semen in jennies, based around ovulation induction with a GnRH analogue.

Study Design: Experimental exploratory study.

Oral misoprostol does not hasten oviductal transport of day-5 horse embryos.

In horses, prostaglandin E (PGE) is produced by embryos around Day 5 post-ovulation; PGE functions directly at the oviduct promoting embryo transport into the uterus. Non-surgical collection of horse embryos for cryopreservation is recommended at Day 6.5-7 post-ovulation.

Horse ooplasm supports in vitro preimplantation development of zebra ICSI and SCNT embryos without compromising YAP1 and SOX2 expression pattern.

Several equids have gone extinct and many extant equids are currently considered vulnerable to critically endangered. This work aimed to evaluate whether domestic horse oocytes support preimplantation development of zebra embryos obtained by intracytoplasmic sperm injection (ICSI, zebroid) and cloning, and to study the Hippo signaling pathway during the lineage specification of trophectoderm cells and inner cell mass cells. We first showed that zebra and horse sperm cells induce porcine oocyte activation and recruit maternal SMARCA4 during pronuclear formation.

Chemotactic selection of frozen-thawed stallion sperm improves sperm quality and heterologous binding to oocytes.

The successful use of assisted reproduction techniques (ART) depends in part on the sperm physiological status. Several sperm selection procedures have been applied to improve quality of sperm population when using the ART. There has previously been development of a Sperm Selection Assay (SSA) for humans which is based on the attraction of capacitated sperm by chemotaxis towards progesterone (P), resulting in an enriched sperm population with an optimal physiological status similar to capacitated spermatozoa, with these cells having very little DNA fragmentation and optimal concentrations of reactive oxygen species (ROS).

Reactive oxygen species are involved in the signaling of equine sperm chemotaxis.

Sperm chemotaxis may facilitate the finding of the oocyte. Only capacitated spermatozoa can orient their movement by chemotaxis, which as well as capacitation, is regulated in part by the cAMP-PKA pathway. Reactive oxygen species (ROS) are produced during sperm capacitation which is closely related to chemotaxis.

Superovulation, embryo recovery, and pregnancy rates from seasonally anovulatory donor mares treated with recombinant equine FSH (reFSH).

The effectiveness of different treatments with recombinant equine FSH to stimulate follicular growth, multiple ovulations and embryo production in seasonally anovulatory mares was evaluated. During mid-winter season (July-August in Argentina, South America) forty light breed donor mares, presenting follicles <10 mm in diameter and no CL at ultrasound examination (deep-anestrus), were randomly assigned (n = 10/group) to one of the following treatments: Group 1: twice daily intramuscular (IM) injections of 0.65 mg reFSH (AspenBio Pharma, CO), Group 2: once daily IM injection of 1.

Effect of the Interval From Prostaglandin F2alpha Treatment to Ovulation on Reproductive Efficiency Rates in a Commercial Equine Embryo Transfer Program.

In the present study, 2.228 cycles of 180 Polo Argentino donor mares from an embryo transfer program in Argentina were examined to evaluate the effects of: (1) Interval from Prostaglandin F2alpha analog treatment to ovulation (ITO) on embryo recovery rate (ERR); (2) ITO on number of embryos per flushing (EPF); (3) ITO on multiple ovulation (MO) rate; (4) ITO from donor mare on pregnancy rate (PR) in recipient mares. Mares were inseminated with fresh semen from 31 fertile stallions in the induced estrus.