title: Comparative Efficacy of an Imidacloprid/Flumethrin Collar (Seresto®) and an Oral Afoxolaner Chewable (NexGard®) against Tick (Dermacentor variabilis and Amblyomma americanum) Infestations on Dogs: a Randomised Controlled Trial.
abstract: This randomised controlled laboratory study demonstrated the residual speed of efficacy of an imidacloprid/flumethrin collar (Seresto(®), Bayer) for the control of ticks (Dermacentor variabilis, Amblyomma americanum) at 6 and 12 hours postinfestation on dogs when compared to oral afoxolaner (NexGard(®), Merial). Dogs were randomised by pre-treatment tick counts: Group 1) imidacloprid 10 % (w/w) / flumethrin 4.5 % (w/w) collar, 2) afoxolaner chewable (dosage 3.1 - 6.2 mg/kg), and 3) non-treated controls. Ticks (50/species/dog) were infested on days 3, 14, 21, and 28; live (attached and non-attached) and dead attached ticks were counted 6 and 12 hours later. Efficacy against live D. variabilis at 6 hours for Group 1 was 95 - 100 % and for Group 2 was 38 - 48 %; efficacy at 12 hours for Group 1 was 97 - 100 % and for Group 2 was 27 - 59 %. Efficacy against A. americanum at 6 hours for Group 1 was 94 - 100 % and for Group 2 was < 0 - 38 %; efficacy at 12 hours for Group 1 was 98 - 100 % and for Group 2 was 1 - 40 %. Live and total (total live and dead attached) tick counts in Group 1 against both tick species were significantly lower (p ≤ 0.05) than Group 2 and 3 at all time points. The number of live or total ticks on Group 2 dogs was never significantly lower when compared to the respective number of ticks on Group 3 (controls). This study demonstrated that an imidacloprid/flumethrin collar was highly efficacious (94 - 100 %) at repelling and killing ticks on dogs at 6 and 12 hours post-infestation and was more efficacious than afoxolaner on all challenge days.
authors.affiliation: Bayer HealthCare, LLC, Animal Health, Shawnee, KS, 66201, USA, Cameon.Ohmes@bayer.com.
authors.forename: Cameon M
authors.initials: CM
authors.lastname: Ohmes
authors.forename: Joe
authors.initials: J
authors.lastname: Hostetler
authors.forename: Wendell L
authors.initials: WL
authors.lastname: Davis
authors.forename: Terry
authors.initials: T
authors.lastname: Settje
authors.forename: William R
authors.initials: WR
authors.lastname: Everett
mesh_terms: D000284:Administration, Oral; D000287:Administration, Topical; D000818:Animals; D004283:Dog Diseases / Q000469:parasitology* / Q000517:prevention & control; D004285:Dogs; D007093:Imidazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D007306:Insecticides / Q000008:administration & dosage / Q000627:therapeutic use; D007555:Isoxazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D026863:Ixodidae / Q000187:drug effects*; D009281:Naphthalenes / Q000008:administration & dosage / Q000627:therapeutic use*; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000008:administration & dosage / Q000627:therapeutic use*; D011722:Pyrethrins / Q000008:administration & dosage / Q000627:therapeutic use*; D013984:Tick Infestations / Q000517:prevention & control / Q000662:veterinary*
chemical_list: D007093:Imidazoles; D007306:Insecticides; D007555:Isoxazoles; D009281:Naphthalenes; D000073943:Neonicotinoids; D009574:Nitro Compounds; D011722:Pyrethrins; C000589002:afoxolaner; C041392:flumethrin; C082359:imidacloprid