08/05/2020
Weather conditions this summer have been favorable for a certain kind of poisoning that can affect cattle on pasture. Cool, damp spring weather followed by warmer temperatures favors grasses becoming infected with ergot bodies. Ergot bodies result from infection of the grain by a fungus called Claviceps purpurea. This fungus grows well in warm weather and infects many different species of grasses throughout the nation. The ergot bodies contain several toxic chemicals produced by the fungus, called ergot alkaloids.
In cattle, these ergot alkaloids can lead to compromised blood flow in the extremities of grazing cattle like the ears, tail and feet. Severe cases result in gangrene, or sloughing off of hooves and the distal parts of ears and tails. Initially, animals may appear painful and lame; this may be initially confused with other causes of lameness on pasture such as foot rot. The extremities of animals affected are cool to the touch and there is a line of demarcation between normal and infected tissue. Other signs that you may see include; increased susceptibility to heat, reduced feed intake, rough hair, weight loss, and decreased milk production. Cattle may also show signs of nervous system problems like excitability and tremors, especially when forced to move. Removing cattle from the affected pasture and providing supportive care is the only known form of treatment.
Recognizing ergot in pasture grasses or feedstuffs is the first step in being vigilant for potential animal problems. The only preventive measure known is removing animals from infected pastures or feedstuffs. Mowing or grazing grass before it flowers will prevent the formation of ergot bodies on grasses.
