Multiple-resistance to ivermectin and benzimidazole of a Haemonchus contortus population in a sheep flock from mainland France, first report

Cazajous, T.; Prévot, Françoise; Kerbiriou, A.; Milhes, M.; Grisez, Christelle; Tropee, A.; Godart, C.; Aragon, Andrew; Jacquiet, P.

doi:10.1016/j.vprsr.2018.09.005

Cited by 14 publications

(16 citation statements)

References 12 publications

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“…4 Instituto de Salud Global de Barcelona (ISGlobal), Barcelona, Spain. 5 Moredun Research Institute, Pentlands Science Park, Edinburgh EH26 0PZ, UK.…”

Section: Supplementary Informationmentioning

confidence: 99%

“…Nowadays, AR has been reported in many GIN species to BZs in many countries and multiple host animals [ 2 ], but also to other drugs such as macrocyclic lactones and even the most recently commercialized anthelmintics, such as monepantel [ 3 ] and derquantel [ 4 ]. The presence of multi-drug resistance to different anthelmintic families has been described in different countries and GIN species [ 5 – 7 ]. Among ruminants, sheep are especially affected by the presence of AR, often being parasitized by Teladorsagia circumcincta , Trichostrongylus spp., Haemonchus contortus , the most prevalent and resistant species [ 3 , 5 – 7 ].…”

Section: Introductionmentioning

confidence: 99%

“…The presence of multi-drug resistance to different anthelmintic families has been described in different countries and GIN species [ 5 – 7 ]. Among ruminants, sheep are especially affected by the presence of AR, often being parasitized by Teladorsagia circumcincta , Trichostrongylus spp., Haemonchus contortus , the most prevalent and resistant species [ 3 , 5 – 7 ].…”

Section: Introductionmentioning

confidence: 99%

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Teladorsagia circumcincta beta tubulin: the presence of the E198L polymorphism on its own is associated with benzimidazole resistance

et al. 2020

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Background Benzimidazole resistance is associated with isotype-1 β-tubulin gene F200Y, E198A and F167Y SNPs. In this study, the recently described polymorphism E198L was reported and analysed in Teladorsagia circumcincta. Methods The benzimidazole phenotypic resistance was measured by the faecal egg count reduction test (FECRT) and the egg hatch test (EHT) using a discriminating dose (DD) in 39 sheep flocks. Around 1000 larvae collected before and after treatment were used for DNA extraction. The resistant species identified in all flocks was T. circumcincta. The resistance alleles frequencies were measured for F200Y and E198A. A 371-bp fragment of the isotype-1 β-tubulin gene was analysed, including the three codons of interest, and a new pyrosequencing assay was designed for testing E198L. Results The percentage of resistant flocks was 35% by FECRT or 26% by EHT; however, F200Y and E198A SNPs were absent in T. circumcincta. The amplification of a 371-bp fragment confirmed the absence of F167Y and F200Y in 6 resistant flocks. Regarding codon 198, all samples after treatment carried a leucine (CTA). A pyrosequencing assay analysed the allele frequencies for the first two bases at codon 198 independently, G/C and A/T. The correlation between C and T frequencies was almost 1 (r = 0.929, P < 0.0001) and the mean value of both was calculated to measure the leucine frequency; this value ranged between 10.4–80.7% before treatment, and 82.3–92.8% after treatment. High and similar correlations were reported between the genotypic variables (C frequency, T frequency or mean of both frequencies) and phenotypic resistance (r > 0.720, P < 0.0001), although negatively associated with the FECRT and positively with the EHT. According to multivariate linear regression analysis, the T frequency was the most significant variable influencing the phenotypic resistance (FECRT or EHT; P < 0.0001). In the EHT, 67.1% of the phenotypic variability is associated with the T frequency but in the FECRT only 33.4%; therefore, the EHT using a DD seems to detect the genotypic resistance more accurately than the FECRT. Conclusions The E198L polymorphism can confer BZ resistance on its own in T. circumcincta.

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“…4 Instituto de Salud Global de Barcelona (ISGlobal), Barcelona, Spain. 5 Moredun Research Institute, Pentlands Science Park, Edinburgh EH26 0PZ, UK.…”

Section: Supplementary Informationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Teladorsagia circumcincta beta tubulin: the presence of the E198L polymorphism on its own is associated with benzimidazole resistance

et al. 2020

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“…Nowadays, AR has been reported in many GIN species to BZs in many countries and multiple host animals [2], but also to other drugs such as macrocyclic lactones and even the most recently commercialized anthelmintics, such as monepantel [3] and derquantel [4]. The presence of multi-drug resistance to different anthelmintic families has been described in different countries and GIN species [5,6,7]. Among ruminants, sheep are especially affected by the presence of AR, often being parasitized by Teladorsagia circumcincta, Trichostrongylus spp., Haemonchus contortus, the most prevalent and resistant species.…”

Section: Introductionmentioning

confidence: 99%

Teladorsagia Circumcincta Beta Tubulin: The Presence of the E198L Polymorphism on Its Own is Associated with Benzimidazole Resistance

Valladares

Valderas-García

Gandasegui

et al. 2020

Preprint

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Background: Benzimidazole resistance is associated with isotype-1 β-tubulin gene F200Y, E198A and F167Y SNPs. In this study, the recently described polymorphism E198L was reported and analysed in Teladorsagia circumcincta.Methods: The benzimidazole phenotypic resistance was measured by the Faecal Egg Count Reduction Test (FECRT) and the Egg Hatch Test (EHT) using a discriminating dose in 39 sheep flocks. Around 1,000 larvae collected before and after treatment were used for DNA extraction. The resistant species identified in all flocks was T. circumcincta . The resistance alleles frequencies were measured for F200Y and E198A. A 371 bp fragment of the isotype-1 β-tubulin gene was analysed, including the three codons of interest, and a new pyrosequencing assay was designed for testing E198L. Results: The percentage of resistant flocks was 32% by FECRT or 26% by EHT, however F200Y and E198A SNPs were absent in T. circumcincta . The amplification a 371 bp fragment confirmed the absence of F167Y and F200Y in 6 resistant flocks. Regarding codon 198, all samples after treatment carried a leucine (CTA). A pyrosequencing assay analysed the allele frequencies for the first two bases at codon 198 independently, G/C and A/T. The correlation between C and T frequencies was almost 1 (r = 0.929; p = 0.000) and the mean value of both was calculated to measure the leucine frequency; this value ranged between 10.4 and 80.7% before treatment, and from 82.3 to 92.8% after treatment. Very high and similar correlations were reported between the genotypic variables (C frequency, T frequency or mean of both frequencies) and phenotypic resistance (r > 0.720; p = 0.000), although negatively associated with the FECRT and positively with the EHT. According to multivariate linear regression analysis, the T frequency was the most significant variable influencing the phenotypic resistance (FECRT or EHT; p = 0.000). In the EHT, 67.1% of the phenotypic variability is associated with the T frequency but in the FECRT only 33.4%; therefore, the EHT using a DD seems to detect the genotypic resistance more accurately than the FECRT. Conclusions: The E198L polymorphism can confer BZ resistance on its own in T. circumcincta .

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“…Western Europe is more and more facing multiple-resistance in GIN 2–4 . In Southwestern France, the first ivermectin and benzimidazoles resistant Haemonchus contortus isolate has been reported recently 5 . In this context, control strategies for GIN that minimize the use of anthelmintics are of increasing importance not only in organic farms but also in conventional farms.…”

Section: Introductionmentioning

confidence: 99%

Cell grazing and Haemonchus contortus control in sheep: lessons from a two-year study in temperate Western Europe

Ruiz-Huidobro

Sagot²,

Lugagne³

et al. 2019

Sci Rep

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Managing infections of sheep with anthelmintic resistant gastrointestinal nematodes (GIN) is a major challenge for sheep producers in Western Europe. New methods of grazing management have been poorly explored as a component of an integrated and sustainable control of these parasites. Therefore, the purpose of this study was to evaluate the effect of two different types of grazing systems of sheep (intensive cell grazing versus conventional rotational grazing) on GIN infections over two years in a farm located in a temperate environment of Western France. When considering the whole study, the type of grazing system did not influence significantly the intensity of egg excretions of adult ewes even if the proportion of ewes excreting high numbers of GIN eggs was higher in cell grazing system than in rotational grazing system. The most striking result of this survey was the effect of grazing system on the GIN species composition harbored by ewes and by their lambs: with time, the proportions of H . contortus infections were lower in cell grazing system than in rotational grazing system. In conclusion, the cell grazing system, as implemented in this study, could limit the importance of this highly pathogenic nematode species in sheep.

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Multiple-resistance to ivermectin and benzimidazole of a Haemonchus contortus population in a sheep flock from mainland France, first report

Cited by 14 publications

References 12 publications

Teladorsagia circumcincta beta tubulin: the presence of the E198L polymorphism on its own is associated with benzimidazole resistance

Teladorsagia circumcincta beta tubulin: the presence of the E198L polymorphism on its own is associated with benzimidazole resistance

Teladorsagia Circumcincta Beta Tubulin: The Presence of the E198L Polymorphism on Its Own is Associated with Benzimidazole Resistance

Cell grazing and Haemonchus contortus control in sheep: lessons from a two-year study in temperate Western Europe

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