Hazards Could be Hidden in Hay

Just 24 hours after Betsy Bueno of Santa Rosa, Calif., began feeding her horses a new batch of hay, one colicked and began to show neurologic signs. Within days, two of her 12 horses required euthanasia and seven were showing similar clinical signs.

"I thought they had gotten some poisonous hemlock outside," Bueno said. But her veterinarian asked to look at her hay.

In the jumble of green material comprising a bale, it can be difficult for a horse owner to spot a dangerous plant, especially in its dried form.

Sharon Gwaltney-Brant, DVM, PhD, Dipl. ABVT, ABT, vice president and medical director of the American Society for the Prevention of Cruelty to Animals' Animal Poison Control Center, recommends testing hay for toxic plants, even if hay is purchased from a familiar source.

"Don't send just one flake," she said. "Compile several small samples from several bales."

Gwaltney-Brant agreed that Bueno's horses did exhibit classical signs of hemlock poisoning, and said she, too, would suspect hay as the likely source.

Although dried hemlock is less toxic than its green counterpart, it still can cause colic, respiratory distress, and muscle tremors in horses that ingest it.

Bueno has learned to inspect bales carefully.

"If you see something that doesn't look right, don't feed it," she said.

About the Author

Pat Raia

Pat Raia is a veteran journalist who enjoys covering equine welfare, industry, and news. In her spare time, she enjoys riding her Tennessee Walking Horse, Sonny.

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