Experiences with transvaginal Ovum Pick-Up (OPU) in sows

Area of Science:

• Veterinary Science
• Reproductive Biology
• Animal Science

Background:

• Transvaginal ultrasound-guided Ovum Pick-Up (OPU) is established in other species but faces challenges in sows.
• Efficient OPU in sows is crucial for in vitro embryo production, gene editing, cloning, and cryopreservation.

Purpose of the Study:

• To improve transvaginal OPU techniques and equipment for sows.
• To assess the feasibility and outcomes of OPU in both anesthetized and non-anesthetized sows.

Main Methods:

• Conducted OPU on Landrace x Large White hybrid sows under general anesthesia (n=3) and in non-sedated, physically restrained sows (n=6).
• Collected cumulus-oocyte complexes and performed post-mortem examinations.
• Monitored salivary cortisol levels in non-sedated sows to assess stress response.

Main Results:

• Recovered an average of 6.6 ± 5.6 oocytes per session in anesthetized sows and 7.7 ± 8.9 in non-sedated sows.
• No major pathological lesions were found in repeated OPU sessions.
• Non-sedated sows showed a short-term increase in salivary cortisol, returning to baseline within 1 hour.

Conclusions:

• The described transvaginal OPU technique and equipment can retrieve a considerable number of oocytes from valuable sows.
• Further research is required to optimize oocyte quality, assess developmental competence, and ensure sow welfare for sustainable OPU.
• One sow inseminated post-experiment successfully delivered 16 piglets, indicating potential reproductive capacity of OPU-derived oocytes.