Equine Reproduction: A New Use for Colostrum

After watching a viral video of a still-wet newborn foal trapped in a pasture hole, animal lovers the world over were filled with joy to see a successful rescue. Knowledgeable horsemen around the world, however, were screaming, “Colostrum! It needs colostrum now!”

“The first milk produced by mares, called colostrum, contains life-saving proteins to fight infection in foals. It must be obtained within the first 12-24 hours of life, preferably earlier, to protect the foal against the barrage of bacteria they are exposed to after birth,” said Laura Petroski-Rose, B.V.M.S., staff veterinarian for Kentucky Equine Research.

Recently, Spanish veterinary researchers reported that colostrum is capable of far more, at least in donkeys.* Colostrum can be added to semen extenders to improve a multitude of semen characteristics after semen samples have been frozen and then thawed, a common practice in many assisted reproductive technologies.

Improved semen characteristics included total motility; specific motility measures (curvilinear velocity, straight-line velocity, linearity, straightness, etc.); sperm cell viability; and cell-membrane integrity.

“In conclusion, the extender containing jenny colostrum can be successfully used for donkey semen cryopreservation and could effectively improve donkey sperm qualities after freezing-thawing,” summarized the researchers.

While this study was conducted in jennies, not mares, any means of improving pregnancy, conception, and live birth rates in horses is welcome. Further research in this field is most certainly warranted.

“Proper stallion and mare nutrition also greatly influences fertility, even in breeding programs reliant on assisted reproduction. Omega-3 fatty acid supplementation with high-quality products such as EO-3 can improve fertility in both genders, and improve colostrum quality,” advised Petroski-Rose.

*Álvarez, C., V. Luño, N. González, et al. A preliminary study on the use of jenny colostrum to improve quality in extenders for freezing donkey semen. Cryobiology. In press.