Time to deworm?
Expert advises sheep, goat owners to be pro-active with treatment now

By KARI KRAMER | East Texas Edition

This time of year, as hay is still one of the main sources of nutrition, sheep and goat producers can treat for worms to deter the development of infestations later in the spring. -- Staff photo

March 3, 2005 - With spring approaching, sheep and goat owners may begin pondering the idea of deworming their flocks.

Dr. Tom Craig, a professor of animal science at Texas A&M University, recommends early spring treatments to offset later parasitic activity.

"This is the time of year that our most important parasites are not being passed at high levels, but they will be soon," said Craig. "If we can use a productive drug at this time of year it will make up for a lot of worming later."

Craig advises producers first get to know the worms on their property.

"People need to know what treatment is working on their farm," said Craig. He suggested knowing what types of worms were present and evaluating the treatment regime used to determine if the drugs being used on the farm are the best choice for that farm.

According to Craig, the most dangerous strain of parasites will not emerge until temperatures heat up near April.

Craig said people generally tend to deworm excessively. He explained that deworming too often helps create resistant strains of parasites, making treatment a challenge.

He added that even when treatment is necessary, only suspect animals should be treated. Craig noted animals with white and pale mucus membranes should be treated. "This tells us the worm is getting more than the animal," said Craig.

According to a Texas Cooperative Extension publication, co-authored by Craig, those animals should be treated and held at least 48 hours before being released on an uncontaminated, or "rested," pasture.

Because the worms can become resistant, Craig advised rotating deworming agents. Every year a new product should be chosen. A week after treatment, a fecal egg count should be taken to determine if the treatment was successful. A 90 to 95 percent decrease in egg count should result after a successful treatment.

Extension information also recommends treating new animals introduced in the flock.

When deworming, estimate weights as closely as possible for dosage purposes, to avoid ineffective treatments. Do not under-estimate the weights for dosage purposes. Follow the directions given with the product.

Craig warned against excessive deworming, but added producers should be aware when treatment is necessary. He said a popular mistake made by producers is believing that no evident problems this time of year suggests there will not be problems in the months to come.