Barber Pole Worms

Necropsy offers insights to parasite control in small ruminants

By John Lovett
University of Arkansas System Division of Agriculture
Arkansas Agricultural Experiment Station

FAYETTEVILLE, Ark. — Parasite control is crucial to the success of small ruminant production says Eva Wray, parasitologist and post-doctoral research associate with the Arkansas Agricultural Experiment Station.

PARASITES — Barber pole worms, seen in a petri dish at the Division of Agriculture's parasitology lab, were a focus of the Northwest Arkansas Small Ruminants Field Day. (U of A System Division of Agriculture photo)

Internal parasites, especially the blood-eating barber pole worm — Haemonchus contortus — were a point of focus during the Northwest Arkansas Small Ruminants Field Day, Oct. 28, at the Milo J. Shult Agricultural Research and Extension Center. The barber pole worm is a nematode that can cause severe anemia, protein loss and death in small ruminants like goats and sheep. Wray provided a session on these and other parasites common in small ruminants.

“All producers should be doing fecal egg counts to determine treatments,” Wray said. “If possible, everyone raising small ruminants should also be doing rotational grazing and grazing with other species like cattle or equines.”

Warmer, wetter weather creates conditions favorable for internal parasite development on pastures. Barber pole infections lead to economic losses including lowered milk production, poor weight gains, substandard wool quality and sudden death in animals of all production stages, Wray added. In addition to rotational grazing, other tips on parasite control in small ruminants include using biological control like Duddingtonia flagrans, a fungus that physically eats nematode larvae on the pasture before they can become infectious. Wray noted that it was also important to know which medications are still effective on their operation.

Lauren Rogers, teaching associate professor and veterinarian, provided field day participants instructions on how to conduct a necropsy, or animal autopsy. This included demonstrations on how the different stomach components look, what the functions are, where to look for parasites and what they look like.

Despite rainy conditions, 51 of the 71 people who registered turned out for the event.

"Simply put, I was most impressed by the level of enthusiasm that the producers displayed to the necropsy,” Rogers said. "They were not at all put off by the less-than-ideal weather conditions, which really speaks to their level of commitment."

Dan Quadros, assistant professor and small ruminant extension specialist said the necropsy provided university-level education to small ruminant producers that is applicable to their daily lives.

“They see the animals every day from the outside, and this may have been the first time they saw the animal from the inside,” Quadros said.

Will and Waltina Hanna of Hanna Family Ranch LLC in Bentonville expressed their appreciation for the necropsy demonstration by Rogers.

“We learned so much during that demonstration that we will definitely use in the future,” Waltina Hanna said. “It is one thing to talk about what to look for when you examine your dead animal, but actually being able to see it done was worth so much.”

Will Hanna said if they can more accurately determine why one of their animals died, they can try to prevent it from happening to others in their flock. The necropsy demonstration was an “unexpected highlight of the morning,” the Hannas said.

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uada.edu. Follow on Twitter at @ArkAgResearch. To learn more about the Division of Agriculture, visit https://uada.edu/. Follow us on Twitter at @AgInArk. To learn about extension programs in Arkansas, contact your local Cooperative Extension Service agent or visit www.uaex.uada.edu.