b'Current options for owners who want to control their mares heat cycles for breeding or performance reasonsWHATS NEW INESTRUSMANIPULATIONCHRISTA LEST-LASSERRE, MAY our mare comes equipped with theBreeding centers must predict estrus accurately for well-signals and structures necessary totimed mating or insemination, says Aurich. With the help reproduce. But nature doesnt alwaysof induction of estrus and ovulation, breeding processes are have the most convenient timing. much easier and, overall, fertility (conception rate) is much improved, she says.Like that time all the shipped semen went bad waiting forLikewise, success of assisted reproduction techniques such Ruby to ovulate. Or that embarrassing moment Ellie stoppedas intracytoplasmic sperm injection and embryo transfer in the middle of a dressage test and winked her vulva at arequire careful control of the estrous cycle to eliminate the flashy Hanoverian stallion. Oh estrus.complication of finding a recipient mare at the right stage of estrus, says Marco Antonio Alvarenga, PhD, of the Depart-All About Estrus ment of Animal Reproduction and Veterinary Radiology at In the five to seven days before ovulating, mares go throughSao Paulo State University, in Botucatu, Brazil.estrus, says Christine Aurich, DVM, PhD, head of the GrafIn performance mares owners might prefer to delay estrus Lehndorff Institute for Equine Science, in Neustadt, Germany.to avoid its undesirable behavior aspects, says Robyn Eller-During this time, the uterus is preparing to accept a pregnan- brock, DVM, PhD, Dipl. ACT, assistant professor of therio-cy, and because semen can live several days inside the maresgenology in the University of Georgias College of Veterinary reproductive tract, she becomes readyboth physiologicallyMedicine, in Athens. Manipulation is necessary in mares and behaviorallyto receive a stallion. that become difficult to work with when in heat, she says.SHELLEY PAULSON24May 2020The Horse|TheHorse.com'