Campus News

New test may help detect costly parasite in sheep

New test may help detect costly parasite in sheep

Researchers at UGA and Oregon State University have developed an improved, more efficient method to test for the most serious parasitic worms in sheep, a problem that causes millions of dollars in losses every year to the global sheep and wool industry.

This technology allows a faster, easier and less expensive way to test for the presence and quantity of Haemonchus contortus or “barber pole” worms, a species that is pathogenic to sheep, goats and llamas. This will help ranchers deal with this problem quickly and effectively. It will optimize their management practices and help them avoid costly therapies.

Findings about the new test were published in Veterinary Parasitology, a professional journal.

The parasite causes significant production losses, and in some cases it’s the limiting factor to sheep production on pasture lands. It can cause internal bleeding, which can lead to anemia, poor food conversion and growth, low protein levels, reduced wool yield and death.

Haemonchus contortus is a blood-sucking parasite that pierces the lining of the sheep’s stomach and can release up to 10,000 eggs per day.

The new lectin staining test is based on a peanut agglutinin that binds to eggs of the parasite and can be seen with a microscope using ultraviolet light. The test is of special value to ranchers interested in organic production, who try to avoid use of chemical treatments.

“One of the current testing tools commonly used by sheep and goat farmers in dealing with H. contortus is the FAMACHA© method, in which the farmer compares the animal’s lower eyelid color to swatches on a card to determine the animal’s anemia status,” said Bob Storey, a UGA researcher who co-developed the lectin staining test. “This method only works in situations where H. contortus is the primary parasite in a given herd’s worm population.

“The new lectin staining test allows for a faster and less expensive method of determining the predominance of H. contortus in a herd worm population, thereby making it easier for producers to determine if FAMACHA© can be a useful tool for them,” he added.