Rye, wheat and barley contaminated with ergot can be fed to cattle if producers are cautious.
“Current recommendations indicate that ergot may be present in a beef cow’s diet at levels up to 0.1 percent of its daily dry matter intake,” said Bryan Doig, livestock agrologist with Saskatchewan Agriculture in North Battleford.
“For example, a 1,200 pound cow eats about 2.1 percent of her body weight each day. This means the cow consumes about 25 lb. of dry matter in a 24 hour period.
“Multiplying 25 lb. by 0.1 percent yields 0.4 ounces, or about 12 grams of ergot. It takes about 10 intact ergot bodies to weigh one gram. A 1,200 pound cow therefore could safely consume up to 12 grams of ergot in a 24 hour period.”
Read Also
Saskatchewan agriculture sector receives federal funding
PrairiesCan funding will assist in the continued growth of Saskatchewan’s ag research and manufacturing sectors.
To reduce or control problems associated with ergot-contaminated grain, it may be diluted with clean grain to reduce the total percentage of ergot, said Doig.
However, grain affected by ergot should never be fed to pregnant or lactating animals.
Various feeding trials indicate ergot levels from 0.1 to 0.5 percent of the total diet reduce feed consumption and rates of gain in feeder cattle. Weight loss in all classes of cattle was also noted.
Clinical signs of ergot poisoning in cows often begin with swelling and pain in the extremities, especially the hind legs. Sensation is eventually lost in the affected areas and dry gangrene can develop.
The affected part, most commonly the hoofs, teats, ears or tails, may slough or fall off.
Cattle can show gangrenous and neurological forms of ergotism. Symptoms of the latter include nervousness, depression and convulsions. It can cause death, but only if significant quantities of ergot are eaten.
The neurological symptoms usually disappear three to 10 days after the contaminated feed is removed. Gangrenous effects are more serious.
Recovery is likely from the neurologic signs of chronic ergotism, which is caused by the cumulative effect of eating unsafe levels of ergot on a continual basis over time, once the source of ergot is removed.
Recovery from gangrene and the vascular effects is less likely.
Ergot poisoning may be a factor in reduced lactation and in abortion among large animals. The poisonous ergot alkaloids are not transferred in milk of cows that consume ergot, however.
Doig said all classes of livestock are susceptible to ergot poisoning. Pregnant and breeding animals are more sensitive to it, while horses, swine, sheep, poultry and cattle, especially feeder cattle, tolerate slightly higher levels. Dairy cows should not be fed rations with ergot.
Horses generally develop symptoms of convulsive ergotism similar to cattle.
Swine usually don’t show signs of convulsive or gangrenous ergotism, but they eat less and show a lower rate of gain. Affected sows have a high incidence of abortion and newborn pigs have a high mortality rate due to reduced lactation by the sows.
Pigs fed grain contaminated with ergot may develop lesions in the gut.
Sheep generally show signs of breathing difficulty, excessive salivation, diarrhea and bleeding in the digestive system.
Poultry can develop comb gangrene. Beaks, toenails and toes may become dark and necrotic. Nervousness, depressed growth, poor feathering, lack of co-ordination and an inability to stand are also common characteristics of ergotism in poultry.
“Ergot bodies contain nearly 40 types of poisonous alkaloids,” Doig said.
“Not only may the concentrations of these alkaloids vary among strains of the fungus, animals differ in their tolerance of the poisons.
“So, if ergotized grain is fed to animals, watch for symptoms of ergotism and if any are observed, proceed with caution.”
