December 2005
Feeding Facts
Fescue Toxicity

Fescue continues to be a predominate pasture grass in Alabama. Fescue is easily established, persistent; tolerant of poor soil conditions, drought resistant, and its productivity under a wide range of temperatures allows cattle producers to provide abundant amounts of forage almost year-round.

There are, however, drawbacks when utilizing fescue grazing and hay. One is forage quality. While fescue will out produce other grasses, it will not provide the overall nutrient quality that other grasses will provide.

The real drawback to fescue is toxicity. Often referred to as "summer slump," fescue toxicity is one of the most frustrating aspects of beef production. The primary cause of the toxicity is a fungus (Neotyphodium coenophialum) that is the same as the fungus that causes ergot in cereal grains. In cattle, death loss is rare, but there are physiological problems that typically translate into impaired performance.

Animals grazing endophyte-infected grass usually show a combination of the following signs: reduced weight gains, reduced feed intake, intolerance to high temperatures, more time spent in the shade or in the water, rough hair coats, elevated body temperatures, faster respiration rates, reduced reproductive performance and hormonal imbalances. During winter months restricted blood flow to extremities, causing gangrene to occur in the foot, ears, and/or tail switch is often referred to as fescue foot. The primary cause of these symptoms is constricting blood vessels preventing cattle from properly regulating temperature and hormonal centers in the brain.

The endophyte is totally contained in the plant, and can be transmitted only through the seed. The endophytic fungus over winters within the plant, and fungus growth occurs in the spring as tiller growth resumes on the plant. Since the primary means of transmission is the seed source itself, this explains why a large percentage of fescue pastures are infected.

Research conducted at Kentucky, Georgia and Auburn proves that grazing poorly managed, high endophyte fescue will adversely affect overall performance of cattle. Research has proven that cattle consuming infected fescue will have lower average daily gains, and higher body temperatures. Research in feedlots also implies that calves coming into the yard off of fescue based forages will eat less, gain less, and have more sickness throughout the feeding program. The same type results were also proven in studies utilizing fescue hay cut after seed heads were present.

While fescue toxicity has been a real concern, new products along with other management practices have been implemented over the past several years to help reduce the problems from grazing fescue. While early improved varieties lacked insect resistance and disease resistance along with stand persistency, new varieties are being introduced that are showing much more favorable results. Just remember that when an infected crop is to be replaced, it must be destroyed by tillage and/or herbicides.

Another area that is gaining more attention is in nutritional management. Several products are now available to help reduce the overall problems associated with infected fescue. Research has again proven that cattle consuming high levels of the trace minerals zinc, copper, manganese and cobalt provided in a form that is easily absorbed show significant performance improvement over cattle consuming lower levels of these minerals. Certain products that have the ability to bind to the toxin also show great potential in reducing the amount of toxin entering the blood stream. Incorporation of products that support proper rumen function, improved fiber digestion, and nutrient utilization, will also help overall performance of the cow even when she is stressed.

A final area in nutritional management that will show favorable results is the incorporation of antioxidants such as selenium and vitamin E into the diet of cattle. While this will not totally end problems with fescue toxicity, it will greatly reduce problems associated with fescue grazing.

Your local cooperative has several products available to improve the nutritional program of your cattle. Your store will carry a variety of Sweetlix Minerals that contain elevated trace minerals as well as chelated minerals that can be provided to your cattle on a daily basis. Crystalyx is also available through your local store and they also carry a line of products that will provide a complete trace mineral program as well as products that will increase fiber digestion. Sweetlix Minerals and Crystalyx Supplement Tubs will also provide needed antioxidants as you manage your fescue grazing.

In conclusion, fescue has many favorable characteristics that make it excellent forage. A pasture and a nutritional management plan should be implemented to help curb the effects of feeding infected fescue. Your local cooperative store has the products and knowledge to assist you in implementing such a plan. I can also be reached at This email address is being protected from spambots. You need JavaScript enabled to view it. and I will also be happy to assist you in any way to implement such a management plan.

Jimmy Hughes is AFC’s animal nutritionist.