August 10, 2015

Toxin blamed for lamb deaths

By Samantha Kneeskern, ASAS Science Communications Intern

A collaborative effort between scientists in the agriculture and human medicine fields determined that a compound termed biliatresone causes biliary atresia in infants and animals.lamb

Biliary atresia is a condition when bile ducts are inflamed and blocked. Bile builds up in the liver and destroys liver cells, causing scarring or cirrhosis. Biliary atresia affects approximately 1 in 18,000 babies and is the main cause of liver transplants in children.

Lambs in Australia were also being born with similar signs and symptoms. Lambs had white feces and would die within the first couple weeks of being born. Following a necropsy, veterinarians found that the lambs did not have gall bladders and had signs of cirrhosis. This was in 1988.

Scientists realized that a similar situation occurred in 1964. In 2007, again, lambs were dying after birth. The connecting factor between the deaths was a drought in New South Wales. During the drought, with limited vegetation, pregnant ewes were consuming plants of the genus Dysphania, commonly called pigweed.pigweed

After further investigation, this year, scientists determined that biliatresone, the toxin from pigweed, causes blockage of  bile ducts. Ranchers in Australia are no longer allowing their ewes to graze on pigweed during gestation and humans are not eating this plant.

More research is currently being conducted to determine if plants humans consume contain biliatresone, hopefully reducing the amount of children affected with biliary atresia.