Wilkinson, V and Tokano, K and Nichols, D and Martin, A and Holme, R and Phalen, D and Mounsey, K and Charleston, M and Kreiss, A and Pye, R and Browne, E and Naesborg-Nielsen, C and Richards, SA and Carver, S, Fluralaner as a novel treatment for sarcoptic mange in the bare-nosed wombat (Vombatus ursinus): safety, pharmacokinetics, efficacy and practicable use, Parasites and Vectors, 14, (1) Article 18. ISSN 1756-3305 (2021) [Refereed Article]
|PDF (Published version)|
© The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) License, (https://creativecommons.org/licenses/by/4.0/) which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
Background: Sarcoptic mange causes significant animal welfare and occasional conservation concerns for bare-nosed wombats (Vombatus ursinus) throughout their range. To date, in situ chemotherapeutic interventions have involved macrocytic lactones, but their short duration of action and need for frequent re-administration has limited treatment success. Fluralaner (Bravecto®; MSD Animal Health), a novel isoxazoline class ectoparasiticide, has several advantageous properties that may overcome such limitations.
Methods: Fluralaner was administered topically at 25 mg/kg (n = 5) and 85 mg/kg (n = 2) to healthy captive bare-nosed wombats. Safety was assessed over 12 weeks by clinical observation and monitoring of haematological and biochemical parameters. Fluralaner plasma pharmacokinetics were quantified using ultra-performance liquid chromatography and tandem mass spectrometry. Efficacy was evaluated through clinical assessment of response to treatment, including mange and body condition scoring, for 15 weeks after topical administration of 25 mg/kg fluralaner to sarcoptic mange-affected wild bare-nosed wombats (n = 3). Duration of action was determined through analysis of pharmacokinetic parameters and visual inspection of study subjects for ticks during the monitoring period. Methods for diluting fluralaner to enable ‘pour-on’ application were compared, and an economic and treatment effort analysis of fluralaner relative to moxidectin was undertaken.
Results: No deleterious health impacts were detected following fluralaner administration. Fluralaner was absorbed and remained quantifiable in plasma throughout the monitoring period. For the 25 mg/kg and 85 mg/kg treatment groups, the respective means for maximum recorded plasma concentrations (Cmax) were 6.2 and 16.4 ng/ml; for maximum recorded times to Cmax, 3.0 and 37.5 days; and for plasma elimination half-lives, 40.1 and 166.5 days. Clinical resolution of sarcoptic mange was observed in all study animals within 3–4 weeks of treatment, and all wombats remained tick-free for 15 weeks. A suitable product for diluting fluralaner into a ‘pour-on’ was found. Treatment costs were competitive, and predicted treatment effort was substantially lower relative to moxidectin.
Conclusions: Fluralaner appears to be a safe and efficacious treatment for sarcoptic mange in the bare-nosed wombat, with a single dose lasting over 1-3 months. It has economic and treatment-effort-related advantages over moxidectin, the most commonly used alternative. We recommend a dose of 25 mg/kg fluralaner and, based on the conservative assumption that at least 50% of a dose makes dermal contact, Bravecto Spot-On for Large Dogs as the most appropriate formulation for adult bare-nosed wombats.
|Item Type:||Refereed Article|
|Keywords:||Fluralaner, sarcoptic mange, Sarcoptes scabiei, bare-nosed wombat, safety, pharmacokinetics, efficacy|
|Research Division:||Biological Sciences|
|Research Group:||Evolutionary biology|
|Research Field:||Host-parasite interactions|
|Objective Division:||Animal Production and Animal Primary Products|
|Objective Group:||Other animal production and animal primary products|
|Objective Field:||Animal welfare|
|UTAS Author:||Wilkinson, V (Miss Victoria Wilkinson)|
|UTAS Author:||Nichols, D (Dr David Nichols)|
|UTAS Author:||Martin, A (Ms Alynn Martin)|
|UTAS Author:||Charleston, M (Professor Michael Charleston)|
|UTAS Author:||Kreiss, A (Dr Alexandre Kreiss)|
|UTAS Author:||Pye, R (Ms Ruth Pye)|
|UTAS Author:||Browne, E (Miss Elizabeth Browne)|
|UTAS Author:||Naesborg-Nielsen, C (Ms Christina Naesborg-Nielsen)|
|UTAS Author:||Richards, SA (Dr Shane Richards)|
|UTAS Author:||Carver, S (Associate Professor Scott Carver)|
|Funding Support:||Australian Research Council (LP180101251)|
|Web of Science® Times Cited:||9|
|Downloads:||11 View Download Statistics|
Repository Staff Only: item control page