Skip to content
Search Library
thumbnail

Most mare owners know the dangers of fescue toxicity—prolonged gestation, scant milk production, difficult birth. Because of these risks, owners scour pastures to be sure tall fescue hasn’t gained a foothold. But endophyte-infected fescue can find its way onto the farm—and into the mouths of mares—in other ways.

When properly fertilized, tall fescue is well known for its hay yield, especially when grown in a grass-legume mixture. For best results, hay is harvested when the first seed heads begin to appear. So long as it is mowed, raked, and baled under proper conditions, fescue hay is palatable and appropriate for certain horses, especially mature, idle horses not in a breeding herd.

Despite its usefulness in some horse-feeding programs, hay made from endophyte-infected fescue poses the same danger to mares as infected pasture, as the endophyte does not become inactive once the hay is harvested or placed in storage. “When it comes to reproductive health of their mares, owners should be just as vigilant about fescue hay as they are about fescue pasture,” advised Kathleen Crandell, Ph.D., nutritionist with Kentucky Equine Research (KER).

Low-quality hay made from tall fescue is sometimes used as bedding for mares and young horses on large breeding farms. Free of dust and mold, the hay acts much like traditional straw. The one possible drawback: fescue toxicity. Once a mare has eaten whatever forage is allotted to her in the stall, she may begin to eat the fescue bedding, which can be infected with the endophyte. With this in mind, mares should be kept off of fescue bedding.

Becoming familiar with hay plants, especially the identification of leaves and seed heads of common plants, will help hay buyers distinguish fescue from innocuous grasses. Tall fescue has numerous dark green, ribbed leaves that roll lengthwise when dried as hay.

“The cost of achieving and maintaining pregnancy in mares is significant, so mare owners should go out of their way to avoid tall fescue, whether it’s in the field, in the bale, or on the stall floor,” said Crandell.

X

Subscribe to Equinews and get the latest equine nutrition and health news delivered to your inbox. Sign up for free now!