Bob Douglas, PhD, owner of BET Labs in Kentucky, specializes in working with veterinarians and farm owners to assist in reproductive problems of mares and stallions. He works with Northern and Southern Hemisphere breeders, and said his clients who maintain mares in Kentucky have suffered losses in all ages of foals.

Southern Hemisphere foals will start being born about Aug. 1 in Kentucky, and some breeders lost half or more of this year’s foals thus far (which would have been about six to eight months gestation).

One thing Douglas and veterinarians have been cautioning breeders about is that some of these mares which lost early fetuses might show heat, but won’t have a breedable follicle. “Just because a mare is teasing in heat doesn’t mean she’ll be bred successfully,” said Douglas. “You have to get rid all luteinized structures, both CLs (corpus luteums) and luteinized follicles.” Glossary of Terms

Douglas explained that with a rise in luteinizing hormone (LH), developing follicles fill with blood and the wall of the follicle gets luteinized and acts as a CL (inhibiting progression of a breedable follicle and return to estrus)