Background and Aim
A reproducible subset of mares develops clinically relevant discomfort during and after ovum pick-up (OPU), despite the use of standardized procedural, sedative, and analgesic protocols.
Through a collaboration between the UC Davis Veterinary Genetics Laboratory (VGL) and the Veterinary Assisted Reproduction Laboratory (VetART), we aim to determine the percentage of mares that experience OPU-associated pain and identify genetic variants affecting nociception or analgesic disposition that may contribute to this susceptibility.
By combining genetic findings with clinical variables, we aim to identify mares that may require individualized or intensified pain-management protocols to optimize animal welfare.
Who Should Submit Samples?
We invite participation from veterinarians and practices performing OPU in more than 20 mares per year. We are particularly interested in practices where mares receive similar procedural, sedative, and analgesic protocols, but a subset of mares experiences unexpected pain during or after OPU while most mares remain comfortable.
Our primary interest is in mares for which the OPU procedure appeared to proceed normally and without an identifiable complication, but the mare nevertheless showed clinically relevant pain or discomfort. Relevant indicators may include:
- Inadequate response to the routine medication dose, requiring additional sedation or analgesia because of discomfort during ovarian manipulation or follicular aspiration.
- Sudden movement, repeated weight shifting, kicking, pawing, repeated straining, or interruption of the procedure during ovarian manipulation.
- Colic or pain-related behavior after an otherwise uneventful procedure, including kicking at the abdomen, persistent restlessness, repeated lying down or rolling, or reluctance to move.
- Markedly reduced appetite or failure to eat during the first 12 to 24 hours after OPU.
- Requirement for veterinary intervention or additional analgesic treatment after OPU.
We need samples from both groups: mares that show unexpected pain and mares that undergo OPU without pain or complications. Mares with an uneventful recovery are essential controls and are equally important to the study.
Whenever possible, please submit both affected and unaffected mares from the same practice so they can be compared under similar procedural and clinical conditions.
Participate in the OPU Pain Study
Veterinarians participating in the study can submit information about the mare, OPU procedure, medications, clinical observations, and submitted samples using the online form. The form also provides sample-preparation instructions, shipping information, and international import-permit requirements.
Complete the Sample Submission Form