A poisoning that can affect cattle on pasture has optimal growing conditions due to this spring and summer weather.
While not spotted in South Dakota yet, ergot bodies have been spotted in states to the south, and ergotism is progressing north, said Russ Daly, an Extension veterinarian for South Dakota State University.
“We’re trying to get the word out ahead of time before it hits the state,” Daly said.
According to a SDSU news release, ergotism begins with ergot bodies that contain several toxic substances that all domestic animals are susceptible to.
Ergot bodies are dark brown to black growths on the top of the seed heads of grasses and grains. These bodies range in size and result from an infection of the grain by a fungus called Claviceps purpurea, which grows well in warm weather and infects more than 200 species of grasses throughout the country.
“We are worried about some of the grain-type grasses. There is also the potential for pasture grasses to be affected,” Daly said.
The colder temperatures in spring, combined with hotter temperatures in summer, make for the optimal growing conditions for the ergot bodies, Daly said. When the bodies will grow is unpredictable, but it tends to occur every four to five years, he said.
While all domestic animals are susceptible, ruminants are more commonly affected than others because of their diets, Daly said.
Symptoms of ergotism in cattle to be aware of, according to SDSU’s news release, are:
• Constriction of the small blood vessels to their extremities, like the ears, tail and feet. Blood flow might be compromised, and in severe cases, results in gangrene or a sloughing off of hooves and the distal parts of ears and tails.
• Initially, the animal might appear to be in pain and lame, and this might be confused with other causes of lameness, such as foot rot.
• Animals affected by ergotism will be cool to the touch.
• Other initial signs of ergotism are nonspecific: increased susceptibility to heat, reduced feed intake, rough hair, weight loss and decreased milk production.
• Cattle will begin to show signs of excitability, and tremors may be present, especially when cattle are forced to move. Other than this, cattle might less commonly show signs of nervous system problems.
Sheep are also susceptible to ergotism, but tend to show milder clinical signs than cattle. Signs of ergotism in swine, according to SDSU’s news release, are:
• Swine will show feed refusal and decreased weight gain if the grain being fed is contaminated.
• Gangrene is less of a problem with swine, but sometimes edges of ears and snouts may slough.
• In sows, ergot is associated with reduced milk production, infertility and early parturition, which results in the birth of smaller, weaker pigs.
How to treat and prevent ergotism, according to the news release:
• Removal of the animals from the offending feed source.
• Provide supportive care to manage pain, stress and secondary infections of the affected body parts.
• Remove animals from infected pasture if possible.
• Mow grass before it flowers to prevent the formation of ergot bodies on grasses.
• If you think your livestock may be affected by ergotism, contact your local veterinarian.