Nontoxic Fescue Varieties Ready To Use; They Produce More Beef On Fewer Acres

By Craig A. Roberts, Justin Sexten

Cattle producers facing fewer grazing acres for herd expansion can boost beef production with better grass.

One answer is more cows on fewer acres, says Justin Sexten, University of Missouri beef nutritionist.

Sexten is part of an Alliance for Grassland Renewal that holds fescue schools across the state.

“How many of you think land taken out of grass for crops will return to grass?” No producer held up a hand at the school held at Columbia. “Pasture land is expensive, or not available,” Sexten said.

A main theme of the schools was to plant nontoxic novel-endophyte tall fescue to replace toxic Kentucky 31, the most widely grown grass in Missouri.

Producers saw results of 14 research studies that show calves grazed on novel fescue gained 0.7 pounds more per day on average compared to calves on toxic K-31.

“You can produce more beef on the land you own,” Sexten said. Better gains are one of many benefits.

During the cold winter, several producers learned the cost of losing cows to “fescue foot.” One farmer lost nine cows out of a herd of 39.

“It’s not only the lost cows, but also costs of replacement heifers,” Sexten said.

Craig Roberts, MU Extension agronomist, described fescue foot as the most visible of losses from toxic fescue.

The toxin, produced by a fungus growing between cell walls of infected fescue, is a vasoconstrictor. It cuts blood flow to animal extremities. That causes feet, tails and ears to freeze. A cow can survive without an ear or tail, but not without a foot.

Toxin also affects an extremity on bulls, causing sterility.  “When you see frost on a bull’s scrotum, you have a problem,” Sexten said.

There is more. The toxin prevents conceptions or causes abortions in pregnant cows. The toxin, ergovaline, resembles LSD and is similar to the toxin found in ergot, a fungus in seedheads of grasses and cereal grains.

Every speaker at the schools told how toxin causes unseen losses in cows grazing K-31.

Producers use the toxic grass because it requires little management. The toxin protects the grass from insects, leaf fungus, nematodes, droughts and overgrazing by cows.

The main reason farmers keep fescue is they don’t see many of the losses, Roberts said. In introducing the program, he told producers, “There is an answer: Renovate and reseed fescue with a new novel endophyte.”

Years ago, MU plant breeders developed endophyte-free fescues. However, without pest defenses of toxic endophyte, the fescues did not persist under heavy grazing.

Plant breeders found other fungi, also endophytes, that protect fescue but don’t poison cattle.

Endophyte in fescue is never seen by most farmers. The schools used a microscope to give views between fescue plant cells. Threadlike fungus is visible only under magnification.

Roberts said “endophyte” is Greek for “in the plant."

Endophyte fungi are found in nature. It happened that the one in the fescue variety that became K-31 was toxic.

“We have known alternatives for years. In extension we try to teach the hazards,” Roberts said. “We had little success.”

“With the Alliance we start over,” he added. “We bring together everyone working on toxic fescue.”  That includes MU, five seed companies, fescue testing labs, nonprofit groups, farmers, agribusinesses and USDA Natural Resources Conservation Service.

Mark Kennedy, retired grassland advisor with USDA, said keeping Missouri hills covered with grass prevents erosion. Some funds from FSA can be used to start grazing systems through the EQIP program.

Source:missouri.edu