December has been a busy month for calls and visits from cattle producers concerned about fescue foot among their herd.
According to Eldon Cole, livestock specialist with University of Missouri Extension, one visit involved a 60-acre pasture that had not been grazed since March.
"The farmer wondered what the risk of fescue foot and other related problems brought on by ergot alkaloids would be if pregnant heifers were allowed to graze it," said Cole.
The other call was a chronic fescue toxicity concern in a set of 100 or so cows. This herd did have fescue foot symptoms present in 15 to 20 percent of the cows, as well as in one herd bull. Symptom is the loss of all or part of the tail switch.
The owner also added there were 17 open cows out of his 60 spring calvers.
"The first situation was a precautionary concern. We know season long, fescue growth that contains the wild endophyte may produce high levels of toxins capable of causing constriction of blood flow to the tail and rear limbs," said Cole.
Samples of the fescue were collected and tested for ergovaline levels.
The test revealed an ergovaline level of 70 parts per billion (ppb). That is below the threshold level of 200 ppb that is used as a level of concern according to Cole.
"The farmer knows that dilution of the heifers' daily ration will add a safety factor when he turns the heifers in on the rank fescue. His supplement will consist of alfalfa and bermuda grass hay and a commodity mix. The supplement level will be about 50 percent of their daily dry matter intake," said Cole.
The herd that already has low conception rates, as well as definite cases of fescue foot is more complicated according to Cole.
"The owner has tried numerous ways to eliminate the fescue toxins. His herd has shown those symptoms for a while," said Cole.
There are many remedies suggested by researchers, veterinarians, extension specialists, neighbors, feed and pharmaceutical companies. Unfortunately, many of those are no help.
Renovating the toxic pastures with a forage that is not toxic, such as novel endophyte fescue, orchard grass, bermuda grass, crabgrass or interseeding legumes into the toxic fescue helps.
"Early December when the first cold weather hits southwest Missouri is when cattle producers need to watch for lameness. It is best to check them early in the day when they're just starting to move around," said Cole.
Affected animals will walk gingerly on their rear limbs. They may pick up a hoof and shake it or turn their head and lick the lower part of the leg.
As the blood flow lessens, due to the toxin, a break in the skin around the top of the hoof, near the dew claws, appears. Farmers often think the animal has a wire wrapped around their pastern or it is foot rot. In severe cases, the hoof may slough off.
"Fescue foot is unpredictable from herd-to-herd, year-to-year, pasture-to-pasture and animal-to-animal. Close observation and prompt action is a must this time of year," said Cole.
Fescue foot was first observed in Missouri in the 1950's and 1960's and was related to grazing fescue pastures that had been in the soil bank program.
For more information, contact any of the MU Extension livestock specialists in southwest Missouri: Eldon Cole in Lawrence County, (417) 466-3102; Andy McCorkill in Dallas County at (417) 345-7551; Dr. Randy Wiedmeier, in Ozark County at (417) 679-3525; or Dr. Patrick Davis in Cedar County at (417) 276-3313.