First report of closantel treatment failure against Fasciola hepatica in cattle

Abstract

Control of Fasciola hepatica infection in livestock is based on annual treatment using flukicides such as triclabendazole, albendazole and closantel. However, triclabendazole resistant F. hepatica populations are emerging worldwide and resistance is emerging to albendazole, whereas it has until now never been described for closantel. In Sweden, a topical formulation containing a combination of closantel and ivermectin (Closamectin Pour On) has been registered for use in cattle only since 2011. This study evaluated the efficacy of closantel against F. hepatica in naturally infected beef cattle using both coproantigen and faecal egg count reduction tests.Faecal egg counts (FEC) and coproantigen ELISA examinations were conducted in February 2014 in three beef cattle herds (A, B, C) in south-western Sweden. On each farm, 10 F. hepatica coproantigen-positive and F. hepatica egg-positive animals were allocated after 12–16 weeks of housing into groups and treated topically with a minimum of 20 mg closantel per kg body weight. Faecal samples were collected from selected animals on 0, 7 and 21 day post-treatment (PT).Based on FEC, closantel efficacy 21 days PT was 72% (95% CI: 65–77%) and 97% (95% CI: 95–98%) on farms A and B, respectively. No FEC reduction at all was observed on farm C. In total, 4, 1 and 6 animals remained coproantigen-positive at 21 days PT on farms A, B and C, respectively.Closantel treatment failure was confirmed on two of the farms. As the animals were housed 12–16 weeks before treatment and thereafter during the entire study, failure due to the presence of juvenile flukes was excluded. Although the cause of closantel failure currently remains unclear, development of resistance or/and absorption failure of topical administration should be considered. To our knowledge, this is the first report of closantel treatment failure against F. hepatica in cattle.

Flukicide efficacy against Fasciola hepatica of Triclabendazole and Nitroxynil in cattle of the central valley of Chile

“…In addition, isolates resistant to Albendazole and sensible to TCBZ have also been described (SANABRIA et al, 2013). A third drug considered here is Closantel, which has been reported with both resistance and sensibility to Fasciola hepatica isolates (HANNA et al, 2015;NOVOBILSKÝ & HÖGLUND, 2015). All of the above underlines the need to study in each location the sensibility of the parasites to drugs administered in order to stop or at least slow down the process of resistance selection.…”

Efficacy of ivermectin against gastrointestinal nematodes of cattle in Denmark evaluated by different methods for analysis of faecal egg count reduction

“…More recently, Bayesian modelling using Markov chain Monte Carlo (MCMC) methods have been advocated as robust statistical analyses to cope with low and aggregated FEC data (Denwood et al., 2010, Torgerson et al., 2014). These MCMC-based procedures, available as open-source R packages or web-interface software, are being increasingly used to infer drug efficacy and to monitor AR in horse nematodes (Denwood et al., 2010, Fischer et al., 2015) and cattle helminths (Neves et al., 2014, O'Shaughnessy et al., 2014, Geurden et al., 2015, Novobilský and Höglund, 2015, Ramos et al., 2016). However, the performance of these MCMC procedures with the low mean FEC and parasite aggregation levels commonly found in cattle has not yet been evaluated.…”

Effectiveness of the Experimental Fosfatriclaben in Comparison with Two Commercial Fasciolicides in Cattle

“…In addition, [23] observed fluke-eggs after treatment with closantel, obtaining 72% and 92% of efficacy. Nevertheless, closantel is still being well recognized as a good fasciolicide and it also shows good efficacy against other parasites such as Haemonchus contortus and Oestrus ovis.…”