When pregnancy loss was detected early enough, 57.3% of mares delivered a live foal the following spring. | Photo: iStock

No breeder wants a mare to lose a fetus or foal. But researchers have learned that when pregnancy loss is detected early enough, some mares can be rebred successfully in the same breeding season with decent foaling rates.

In a study of 82 Thoroughbred mares rebred after early pregnancy loss, 57.3% delivered a live foal the following spring, said Yasuo Nambo, DVM, PhD, of the Obihiro University of Agriculture and Veterinary Medicine, in Hokkaido, Japan.

“The observed foaling rate of the mares following rebreeding in the same reproductive season after pregnancy loss was lower than the foaling rates of 69–79% that have been reported in previous studies on Thoroughbred mares,” the researchers noted. “However, it was still relatively good considering that all of the mares had experienced pregnancy loss