Fescue Foot Is Right On Schedule Says Livestock Specialist

MT. VERNON, MO.
   Year-in and year-out, fescue foot occurs in late November and early December somewhere in southwest Missouri. That was the case again in 2010 according to Eldon Cole, a livestock specialist with University of Missouri.
   “It wasn’t a big surprise as weather conditions had been favorable for fescue problems from the dry late summer, a wet, good growing period in September and seasonally cold weather around Thanksgiving,” said Cole.
   Fescue foot has been showing up since the 1950’s when it seemed associated with rank fescue growth on fields that came out of the soil bank program.
   “For years, farmers knew the problem could develop under those conditions, but researchers were unable to pinpoint the exact cause,” said Cole. “It was known something caused lameness primarily in the rear hooves or lower legs.”
   Left unattended, a break in the skin from the top of the hoof up to the hock could develop. In time, the area below the skin break could slough off.
   In addition to the hoof problems, animals with fescue foot would draw up and waste away. The only successful treatments were a quick diagnosis of the problem, removal from the pasture where the problem occurred, and quickly feeding a high quality, non-fescue ration in a small area where water was easily accessible.
   “Little by little, researchers found that there was a fungus in the fescue plant that produced a toxin that caused a constriction of the blood vessels in the animal,” said Cole.
   The loss of blood flow to the extremities contributed to the lameness and ultimately frostbite in the areas far from the animal’s heart, like the rear limbs and tail switch.
   The culprit toxin was identified as one of the ergot alkaloids with ergovaline the most prevalent one found in toxic fescue.
   The perplexing problem is fescue foot problems do not surface in the same pastures every year.
   “We feel the weather, fertility and management practices influence fescue foot outbreaks. There apparently are also animal differences because in a herd of 30 cows, only 3 or 4 may develop the lameness even though they are all grazing the same pasture,” said Cole.
   Research into fescue toxicosis problems including fescue foot, do not seem to be high on the priority list.
   “From a cattle owner’s perspective, they need to be observant of their cattle for early signs of lameness. Checking them early in the morning as they arise and start moving around is best,” said Cole.
   Any cattle that show slowness or reluctance to get up and lameness in the rear feet should be pulled off that pasture according to Cole. Antibiotic treatment will not be effective, other than reducing infection risks.
   “Some cows do not show lameness but may still lose their tail switches later in the winter. Hoof growth, especially the rear toes, may occur in a few months in some animals,” said Cole. The novel endophyte fescues and fungus free varieties do not show toxicity problems. Δ