Source: James Carpenter, 785-532-4269, carpentr@ksu.edu
http://www.k-state.edu/media/mediaguide/bios/carpenterbio.html
News release prepared by: Jennifer Torline, 785-532-0847, jtorline@k-state.edu

Monday, Aug. 30, 2010

RESEARCH SHOWS THAT SELAMECTIN IS SAFE FOR RABBITS AND HIGHER DOSES ARE NEEDED TO EFFECTIVELY TREAT FLEAS

MANHATTAN -- Selamectin, a widely used product that kills parasites in dogs and cats, is an effective treatment for fleas in pet rabbits, according to a Kansas State University research team.

James Carpenter, professor of zoological medicine, collaborated with Michael Dryden, professor of diagnostic medicine and pathobiology, and Butch KuKanich, an associate professor of anatomy and physiology. The team recently found that not only is topical selamectin safe to use on rabbits, but rabbits also need a higher dose of the drug than dogs and cats to effectively get rid of fleas.

Carpenter wanted to look at pet rabbits because more veterinary clinics are seeing exotic animals, especially small animals such as rabbits, ferrets and guinea pigs. He said exotic animal medicine is rapidly becoming an integral part of most companion animal practices, and more households report owning rabbits than any other exotic animal.

"Selamectin is widely used with dogs and cats, but there has never been a combined pharmacokinetic and efficacy study conducted on an exotic animal," Carpenter said.

The researchers had three goals: to determine the safety and efficacy of selamectin topically on rabbits with a known quantity of fleas; to discover how quickly selamectin is absorbed and how long it works in the animal; and to see what dose and treatment intervals of selamectin would be effective to get rid of fleas.

Pfizer Animal Health contributed $25,000 for the project.

Researchers found that there were no adverse effects of using selamectin on rabbits, and that transdermal selamectin is more quickly absorbed, metabolized and eliminated in the rabbit than in the cat and dog.

"Veterinarians who were using selamectin based on dog and cat dosages were giving it at too low a dose and less frequently than needed," Carpenter said. "We're recommending 15 to 20 milligrams per kilogram topically every seven days for flea infestations in a rabbit."

Previously, most veterinarians were applying selamectin topically on rabbits at 6 to 10 milligrams per kilogram per month.

While the results of the study lay the foundation for flea control in rabbits, the researchers said that further studies are needed to ensure that the recommended dose is safe and effective for all rabbits, including different breeds and ages, as well as for those with underlying health problems.

Carpenter presented "Efficacy and Pharmacokinetics of Selamectin in the Pet Rabbit" at the 31st annual conference of the Association of Avian Veterinarians/Association of Exotic Mammal Veterinarians in San Diego in early August.

"We received a lot of compliments regarding our research," Carpenter said. "Our veterinary colleagues were pleased to see the results so they can now administer the proper dose."

The team is in the process of writing a manuscript for a veterinary journal and hopes to distribute the scientific findings internationally.