The work reported

herein was funded by Merial Limited, GA, USA. The authors are current employees or contractors of Merial. All studies were funded by Merial Limited. The authors gratefully acknowledge the staff at BerTek, Inc. (Greenbrier AR, USA) and at Merial Limited for their help in conducting the studies to a high professional standard. The authors gratefully acknowledge Michael Murray and Frederic Beugnet for the scientific editing of the manuscript. “
“Tick control is an important concern for public health officials, pet owners, and veterinarians (Dantas-Torres et al., 2012 and Mencke, 2013). Ixodes scapularis ticks have become an increasingly important concern ATM/ATR inhibitor drugs for public and veterinary health ( Dantas-Torres et al., 2012 and Otranto and Wall, 2008). These ticks can carry a variety of infectious agents, some of which are zoonotic and may be life-threatening, including the organisms that cause Lyme borreliosis,

babesiosis, and ehrlichiosis in both dogs and humans ( Chomel, 2011, Colwell et al., 2011 and Varde et al., 1998). The geographic distribution of I. scapularis ticks is also expanding, in part through infestation of migratory birds ( Hamer et al., 2012 and Ogden selleck kinase inhibitor et al., 2008). Several tick species, including I. scapularis, are also capable of transmitting a salivary neurotoxin that can block acetylcholine transmission and lead to flaccid paralysis in dogs and humans ( Blagburn and Dryden, 2009 and Vedanarayanan et al., 2004). There are several strategies available to control tick infestations, including avoidance of infested environments, particularly during periods when ticks are active (Otranto et al., 2009 and Blagburn and Dryden, 2009). Regular administration of an acaricide is also important since old owners may not be aware of what tick species are common in their area and avoiding infested environments may be difficult. There are many topically applied acaricidal products currently available as spot-on formulations

or collars. These compounds, which can be highly efficacious against some tick species, include amitraz, fipronil and pyrethroids (permethrin, deltamethrin, and flumethrin) (Beugnet and Franc, 2012). Despite their reported effectiveness, there are some concerns about the use of topical products due to differences in dogs’ hair coats that may affect efficacy, adverse effects of shampooing or bathing after application on efficacy, possible toxic effects of products on non-target species, or cosmetic concerns (Dryden and Payne, 2004 and Malik et al., 2010). Therefore, an orally administered acaricide may be preferable for many pet owners. Afoxolaner is a novel insecticide–acaricide administered orally in a chewable formulation (Nexgard®, Merial) designed to treat and control fleas and ticks on dogs. This paper describes an experimental study that was performed to demonstrate the efficacy of afoxolaner against I.