Internal parasite control continues to be one of the most important and difficult to manage health issues for sheep and goat farmers. Traditional control strategies with preventive or suppressive treatments with dewormers have lead to widespread resistance to the drugs we currently have available.

Although many farmers have not yet experienced complete failure of a dewormer, many have, and those who haven’t often do not have the objective data to realize just how much loss is occurring from reduced animal performance. Although a new dewormer of a different drug class, monepantel, was recently introduced in Australia and New Zealand, it is not clear how soon we might see this new class of dewormer available here in the United States.

What is clear is that if we use it in the same ways we have used dewormers over the last 40 years, we can expect to see the first reports of resistant worms within three to five years of its introduction.

We select dewormer-resistant worms in many ways: frequent use of a drug; underdosing animals; deworming all animals and moving them to a “clean” pasture; and deworming animals that don’t really need treatment such as ewes in good body condition in late summer or early fall.

Successful implementation of the current concepts of internal parasite control requires a good working knowledge of parasite biology, a basic understanding of pasture management approaches that can minimize or reduce risk for grazing animals, and an assessment of your ability to plan an integrated approach to controlling parasite burdens. Each farm’s situation will usually be somewhat different because of opportunities and goals.

Over the last several years several Extension educators, researchers, and farmers in Ohio and West Virginia have been involved in various projects to develop or demonstrate strategies to assist in controlling internal parasites.

The Internet-based meetings will be held from 7-9 p.m. on Thursday evenings August 18 and concluding on August 25. The presentations will be given sequentially in Morrow, Athens, and Wayne counties, but other sites where people can participate will also be available throughout Ohio.

People can also access these meetings from home if they have a high-speed Internet connection and a telephone connection. A field day concluding the series is set for August 27 at the John Anderson farm near Wooster. At the field day attendees will have a chance to receive hands-on FAMACHA training, learn about using non-traditional forages in a grazing program for managing parasitism, and see examples of various forages and fencing options.

In addition, other presentations on selecting sheep, sheep nutrition, and biosecurity and animal health will be given. The sponsors for these events are OSU Extension, NC SARE, the Ohio Sheep Improvement Association, and the Ohio Heartland Sheep Improvement Association.

Specific information about locations for attending the evening sessions, connecting to the sessions from other sites, and program and field day topics are posted on the OSU Veterinary Extension web site at http://vet.osu.edu/extension/sare/parasite_control. You can also contact Dr. Bill Shulaw at shulaw.1@osu.edu, Jeff McCutcheon at mccutcheon.30@osu.edu, or Rory Lewandowski at lewandowski.11@osu.edu for more information.