Researchers propose ethical checklist for ovum pick-up in mares

Assisted reproductive technologies can accelerate genetic improvement in selective horse breeding and address specific reproductive challenges. One of the most recent in domestic horse breeding is ultrasound-guided transvaginal follicular aspiration, known as OPU, combined with intracytoplasmic sperm injection, ICSI. Like other breeding methods, it raises ethical questions about animal welfare, staff safety and the integrity of professional and veterinary practice. An article published on 22 August 2026 in Theriogenology proposes a way to monitor those questions in daily practice.

The authors, from European institutions, developed an ethical self-assessment checklist organised in three dimensions: animal welfare ethics, professional ethics and procedural ethics. The instrument was built and tested through an iterative process with a panel of 14 experts in OPU procedures and applied ethics. Stated aims include reducing procedural risks and protecting animal welfare; the self-assessment approach, according to the abstract, enables professionals to highlight issues that might otherwise be overlooked in daily practice and to ensure procedures adhere to high ethical standards. The abstract does not describe the checklist items; the full text is needed to know them.

A survey published days later, on 27 August 2026, in the Equine Veterinary Journal measured how veterinarians and sport horse breeders perceive the ethics of OPU-ICSI. Three questionnaires drew 225 responses from breeders, 92 from veterinarians performing OPU and 112 from general equine practitioners. Among veterinarians not performing OPU, 58.8% rated the technique ethically challenging (scores of 4 or 5 on a 5-point scale), as did 55.2% of breeders not using it. Among those who practise it, the proportions fall to 35.2% of veterinarians and 19.6% of breeders.

Despite the divergence, mare welfare was the main theme across all groups, followed closely, among breeders, by concern over genetic diversity and overuse. The authors acknowledge the potential for motivational and response bias and conclude that the mare's experience during OPU needs to be better characterised to support evidence-based guidance for clinical and breeding practice.

To understand what is under discussion, it helps to look at the numbers from an established clinical programme, published in 2022 in Theriogenology. In 515 OPU-ICSI sessions performed in 2021 at a European university clinic, a mean of 25.9 follicles were aspirated per session, yielding 13.8 immature oocytes shipped to a specialised laboratory. One or more blastocysts were produced from 78% of procedures, with a mean of 2.12 per session, and the likelihood of pregnancy after transfer of 781 cryopreserved blastocysts was 77.7%. About 60% of transferred blastocysts yielded a foal, with no noticeable effect on gestation length or foal health. The authors record that serious complications after OPU are uncommon but exist, and some can be life-threatening for the mare, which is why owners should be informed.

The three papers describe an effective technique with known risks and a split in perceptions that tracks familiarity with the procedure. The self-assessment checklist proposed in 2026 is an attempt to give written form to concerns that, according to the survey, everyone involved says they hold. This summary neither evaluates the technique nor guides its indication; for decisions about breeding programmes, the full articles and the assessment of a veterinarian specialised in equine reproduction are the path.