First Cut: A dose of toxicosis

Even the name — fescue toxicosis — sounds like life support is eminent.

Though it’s been known about for years, fescue toxicosis continues to haunt the livestock industry in a manner similar to human type 2 diabetes: The afflicted still function, but often not at peak performance.

It’s estimated that tall fescue resides on about 35 million acres of pasture and hay land in the U.S. Much of that acreage is in the lower Midwest and South, the so-called Fescue Belt. A lot of those acres are also Kentucky 31, a variety that’s been around for north of 80 years and one that contains toxic ergot alkaloids. That’s not new information for the majority of Hay & Forage Grower readers.

In his article that begins on page 24, Glen Aiken states that fescue toxicosis is estimated to cost the beef industry over $1 billion annually. Add in losses to the dairy, sheep and horse industries. Over many years, millions of research dollars have been spent to find answers to the problem. Solutions do exist, some easier and less costly than others. Aiken, a USDA-ARS research scientist in the heart of fescue country, discusses novel endophyte varieties and pasture conversion in this issue and will address strategies to manage around the problem in our next edition.

Fescue toxicosis is a complex problem; so is eradicating 35 million acres of endophyte-infected tall fescue. I was talking to one well-known commercial Angus producer this winter who sells breeding stock throughout the Fescue Belt and beyond. Many of his pastures were infected tall fescue, but he preferred to manage around the issue by doing things such as offering supplemental feeds like soybean hulls.

“I don’t know where these cattle are going once they leave our place,” said the producer. “If they aren’t exposed to infected fescue here and get shipped to a farm that has it, they’ll go downhill in a hurry.”

Effectively, this producer was willing to accept a low level of toxicity in his own cattle to maintain the farm’s reputation for selling animals that are adaptive to a range of conditions. This demonstrates the complexity of the issue, but it also shows that the problem can be effectively dealt with even when pastures are endophyte infected.

On a different Angus ranch I visited last June, hundreds of acres had been sprayed several weeks earlier with Chaparral herbicide to suppress tall fescue seedheads. Seedheads contain a high concentration of ergot alkaloids. While the practice reduces overall biomass yields, operators of this large ranch felt the trade-off was worth the expense and effort to maintain animal health.

It’s unrealistic to think that 35 million acres of infected fescue are going to be destroyed and reseeded to novel endophyte varieties. That said, at least some acres on many farms probably should undergo such a transition and be targeted for summer grazing when the risk and effects of toxicosis are the greatest; read Aiken’s plan for success.

Science has provided many answers. For infected acres, there are strategies to help alleviate the negative effects of grazing such pastures. Dilution, whether it is supplemental feeds, interseeded legume species or other grass alternatives, is always a solution. One billion dollars is a lot of money to leave on the table.

Not a subscriber? Click to get the print magazine.