Canine semen cryopreservation, fundamentals
From collection to straw: why post-thaw motility alone is not enough.
Cryopreservation of canine semen enables long-term storage and international genetic exchange but comes with a well-documented drop in fertility relative to fresh semen. Sound protocols and honest quality metrics matter.
- Post-thaw progressive motility of at least 50% is a common minimum acceptance criterion for banking.
- Egg-yolk–based extenders with glycerol remain the most widely used freezing medium.
- Intrauterine deposition (surgical or transcervical) is required for acceptable fertility with frozen semen.
- Membrane integrity assessed by fluorescent staining correlates with fertility better than motility alone.
The workflow
Collection by manual stimulation, fractional evaluation of the ejaculate, extension in a validated medium, cooling curve, glycerol equilibration, freezing in vapor and storage in liquid nitrogen at -196°C.
Quality control
A responsible banking protocol documents pre-freeze and post-thaw motility, morphology, membrane integrity and, ideally, longevity at 37°C. Reports without post-thaw metrics should be considered incomplete.
Clinical caveats
Freezing does not fix a suboptimal ejaculate. Fertility work-up and any clinical procedure remain the responsibility of a licensed veterinarian.
References
- Linde-Forsberg C. Regulations and recommendations for international shipment of chilled and frozen canine semen. Theriogenology.
- Peña AI, Núñez-Martínez I. Canine sperm cryopreservation. Reprod Dom Anim.
Educational information only. Does not replace veterinary consultation. No diagnosis. No prescriptions. No emergency advice.