1
|
Gravdal M, Woolsey ID, Robertson LJ, Höglund J, Chartier C, Stuen S. Occurrence of gastrointestinal nematodes in lambs in Norway, as assessed by copromicroscopy and droplet digital polymerase chain reaction. Acta Vet Scand 2024; 66:22. [PMID: 38796502 PMCID: PMC11127287 DOI: 10.1186/s13028-024-00743-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 05/07/2024] [Indexed: 05/28/2024] Open
Abstract
BACKGROUND Gastrointestinal nematodes (GINs) have a major impact on sheep production, health, and welfare worldwide. Norway is no exception, but there are only a few studies on the prevalence of GINs in Norwegian sheep. The aim of this study was to investigate the current occurrence of the most important nematodes in sheep flocks in Norway. Faecal samples were collected from flocks in 2021/2022, mainly from three geographical regions in Norway, i.e., northern, eastern, and western. In each of 134 flocks included, individual samples from 10 lambs (autumn) were pooled. Third stage larvae (L3) were cultivated and harvested (Baermann method) from the pooled samples. The DNA was then extracted and further analysed using droplet digital PCR (ddPCR). This enables assessment of the proportions of the three most important nematode species/genera, i.e., H. contortus, T. circumcincta, and Trichostrongylus. The fractional abundance/relative proportion of each species/genus was assessed by performing duplex assays with universal strongyle and species/genus-specific primers and probe sets. In addition, the occurrence of Nematodirus eggs was assessed by standard faecal egg counts (i.e., McMaster method). RESULTS Of the 134 flocks sampled, 24 were from the northern region, 31 from eastern, and 71 from western Norway. In addition, some flocks from central (n = 7), and southern (n = 1) Norway were included. Among the sampled flocks, T. circumcincta occurred most commonly (94%), followed by H. contortus (60%) and Trichostrongylus (55%), and Nematodirus (51%). In general, mixed infections were observed, with 38% and 18% of flocks infected with three or all four genera, respectively. CONCLUSIONS The results of this study indicate that GINs are widespread in Norway. Teladorsagia circumcincta seems to be present in most flocks based on this screening. Moreover, the results show that Nematodirus spp. infect lambs throughout the country, predominantly N. battus, and indicate that this nematode has become more abundant, which could lead to an increase in nematodirosis.
Collapse
Affiliation(s)
- Maiken Gravdal
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Svebastadveien 112, 4325, Sandnes, Norway.
| | - Ian David Woolsey
- Department of Paraclinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Elizabeth Stephansens Vei 15, 1433, Ås, Norway
| | - Lucy Jane Robertson
- Department of Paraclinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Elizabeth Stephansens Vei 15, 1433, Ås, Norway
| | - Johan Höglund
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Box 7028, 75007, Uppsala, Sweden
| | | | - Snorre Stuen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Svebastadveien 112, 4325, Sandnes, Norway
| |
Collapse
|
2
|
Kapo N, Omeragić J, Goletić Š, Šabić E, Softić A, Smajlović A, Mujezinović I, Škapur V, Goletić T. First Report of Benzimidazole Resistance in Field Population of Haemonchus contortus from Sheep, Goats and Cattle in Bosnia and Herzegovina. Pathogens 2024; 13:77. [PMID: 38251384 PMCID: PMC10818805 DOI: 10.3390/pathogens13010077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/24/2023] [Accepted: 12/28/2023] [Indexed: 01/23/2024] Open
Abstract
Haemonchus contortus is a globally significant parasitic nematode in ruminants, with widespread resistance to benzimidazole due to its excessive and prolonged use. Given the extensive use of benzimidazole anthelmintics in Bosnia and Herzegovina, we hypothesized that resistance is prevalent. The aim of this study was to identify the presence of anthelmintic resistance to benzimidazole in H. contortus from naturally infected sheep, goats and cattle in Bosnia and Herzegovina through the detection of the Phe/Tyr polymorphism in the amino acid at position 200 of the β-tubulin protein. From 19 locations in Bosnia and Herzegovina, a total of 83 adult H. contortus were collected from the abomasum of ruminants. Among these, 45 H. contortus specimens were isolated from sheep, 19 from goats and 19 from cattle. Results showed that 77.8% of H. contortus in sheep exhibited homozygous resistant genotypes at position 200 of the β-tubulin gene, with 15.5% being heterozygous. In goats, all tested H. contortus (100%) were homozygous resistant, and no heterozygous resistant or homozygous sensitive genotypes were found. Cattle had 94.7% homozygous resistant H. contortus, with no heterozygous resistant genotypes detected. In H. contortus from sheep and cattle, 6.7% and 5.3%, respectively, displayed homozygous sensitive genotypes. This study, for the first time, highlights the presence of a resistant population of H. contortus in sheep, goats and cattle in Bosnia and Herzegovina, using the rt-qPCR method. The resistance likely spread from sheep or goats to cattle, facilitated by shared pastures and the practice of transhumance, indicating a widespread and growing issue of anthelmintic resistance.
Collapse
Affiliation(s)
- Naida Kapo
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Jasmin Omeragić
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Šejla Goletić
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Emina Šabić
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Adis Softić
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Ahmed Smajlović
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Indira Mujezinović
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| | - Vedad Škapur
- Faculty of Agriculture and Food Science, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina;
| | - Teufik Goletić
- Veterinary Faculty, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina; (J.O.); (Š.G.); (E.Š.); (A.S.); (A.S.); (I.M.); (T.G.)
| |
Collapse
|
3
|
Höglund J, Daş G, Tarbiat B, Geldhof P, Jansson DS, Gauly M. Ascaridia galli - An old problem that requires new solutions. Int J Parasitol Drugs Drug Resist 2023; 23:1-9. [PMID: 37516026 PMCID: PMC10409999 DOI: 10.1016/j.ijpddr.2023.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/20/2023] [Accepted: 07/22/2023] [Indexed: 07/31/2023]
Abstract
Reports of Ascaridia galli in laying hens in Europe have increased since the ban on conventional battery cages in 2012. As this parasite is transmitted directly via the faecal-oral route by parasite eggs containing a larva, it is reasonable to assume that the escalating problem is related to the increased exposure now occurring in modern welfare-friendly cage-free housing systems. On many farms, A. galli reappears in subsequent flocks, even though the birds have no access to the outdoors, biosecurity is high and empty houses are cleaned and disinfected during downtime. Since the egg production cycle lasts only ≈80 weeks and recombinant antigen production for helminth vaccines has not yet been solved, the development of a vaccine seems to be an unrealistic option. Therefore, disrupting the life cycle of the parasite by other means, including the strategic use of dewormers, appears to be the key to controlling infection. Of concern is that only one class of anthelmintics is licenced for poultry in Europe and that are usually administered indiscriminately through the birds' drinking water and often too late when the parasite is already established. If current calendar-based parasite control strategies are not changed, there is a risk that resistance to anthelmintics may develop, as has already been demonstrated with nematodes in livestock. We insist that treatments can be more effective and the risk of developing drug resistance can be mitigated if we invest in a better understanding of A. galli responses to more prudent and judicious use of anthelmintics. This review identifies knowledge gaps and highlights aspects of sustainable parasite control that require further research to support commercial egg producers.
Collapse
Affiliation(s)
- Johan Höglund
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| | - Gürbüz Daş
- Institute of Nutritional Physiology 'Oskar Kellner', Research Institute for Farm Animal Biology (FBN), Wilhelm-Stahl-Allee 2, 18196, Dummerstorf, Germany.
| | - Behdad Tarbiat
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| | - Peter Geldhof
- Laboratory for Parasitology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820, Merelbeke, Belgium.
| | - Désirée S Jansson
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| | - Matthias Gauly
- Free University of Bolzano, Department of Animal Science, Piazza Università 5, 39100, Bolzano, Italy.
| |
Collapse
|
4
|
Gravdal M, Woolsey ID, Robertson LJ, Höglund J, Chartier C, Stuen S. Benzimidazole-resistance associated mutation in Haemonchus contortus in Norwegian sheep, as detected by droplet digital PCR. Vet Parasitol Reg Stud Reports 2023; 46:100938. [PMID: 37935539 DOI: 10.1016/j.vprsr.2023.100938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 09/05/2023] [Accepted: 10/05/2023] [Indexed: 11/09/2023]
Abstract
The aim of this study was to investigate the occurrence of benzimidazole-resistant Haemonchus contortus in Norwegian sheep flocks. Screening was based on detection of one of the resistance-conferring mutations in the β tubulin isotype 1 gene (F200Y, TAC) in larvae (L3) cultivated from H. contortus eggs from naturally infected sheep. Faecal samples were collected in 2021/2022 from flocks in the northern (n = 34), central (n = 7), eastern (n = 40), southern (n = 1), and western (n = 87) areas of Norway. In total, samples were taken from 169 flocks (spring-ewes samples: 167, autumn-lambs samples: 134). Individual faecal samples were collected from 10 randomly selected ewes (spring) and 10 randomly selected lambs (autumn) in each flock. Faecal samples collected from each flock on each occasion were pooled (lamb and ewe samples pooled separately) and cultured for L3 development. After harvest of larvae (Baermann method), DNA was extracted and then analysed using droplet digital PCR with primer/probe sets targeting the BZ-associated F200Y (TAC) mutation. Haemonchus was found in 60% (80/134) of samples from lambs, and in 63% (106/167) from ewes. Among these, the F200Y mutation was detected in 73% (58/80) of larval samples from lambs and 69% (73/106) of larval samples from ewes, respectively. Although regional differences were evident, the mutation was detected in all areas indicating a widespread distribution and a strong potential for an increasing problem with treatment-resistant haemonchosis in Norwegian sheep flocks.
Collapse
Affiliation(s)
- Maiken Gravdal
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 4325 Sandnes, Norway.
| | - Ian D Woolsey
- Department of Preclinical Sciences and Pathology, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 1433 Ås, Norway
| | - Lucy J Robertson
- Department of Paraclinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 1433 Ås, Norway
| | - Johan Höglund
- Swedish University of Agricultural Sciences, Department of Veterinary Public Health, Section for Parasitology, P.O. Box 7036, Uppsala, Sweden
| | | | - Snorre Stuen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences, 4325 Sandnes, Norway
| |
Collapse
|
5
|
Baltrušis P, Höglund J. Digital PCR: modern solution to parasite diagnostics and population trait genetics. Parasit Vectors 2023; 16:143. [PMID: 37098569 PMCID: PMC10131454 DOI: 10.1186/s13071-023-05756-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 03/23/2023] [Indexed: 04/27/2023] Open
Abstract
The use of polymerase chain reaction (PCR)-based diagnostic approaches has steadily increased in the field of parasitology in recent decades. The most recent large-scale technological modification of the PCR formula, also known as third-generation PCR, came in the form of digital PCR (dPCR). Currently, the most common form of dPCR on the market is digital droplet PCR (ddPCR). Unlike quantitative real-time PCR (qPCR), the digital format allows for highly sensitive, absolute quantification of nucleic acid targets and does not require external standards to be included in the developed assays. Dividing each sample into thousands of compartments and using statistical models also eliminates the need for technical replicates. With unprecedented sensitivity and enforcement of binary endpoint reactions, ddPCR not only allows the use of tiny sample volumes (especially important when working with limited amounts of DNA) but also minimises the impact of variations in amplification efficiency and the presence of inhibitors. As ddPCR is characterised by excellent features such as high throughput, sensitivity and robust quantification, it is widely used as a diagnostic tool in clinical microbiology. Due to recent advances, both the theoretical background and the practical, current applications related to the quantification of nucleic acids of eukaryotic parasites need to be updated. In this review, we present the basics of this technology (particularly useful for new users) and consolidate recent advances in the field with a focus on applications to the study of helminths and protozoan parasites.
Collapse
Affiliation(s)
- Paulius Baltrušis
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Johan Höglund
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| |
Collapse
|
6
|
Dolinská MU, Königová A, von Samson Himmelstjerna G, Várady M. Variation in allele frequencies in benzimidazole resistant and susceptible isolates of Haemonchus contortus during patent infection in lambs. Sci Rep 2023; 13:1296. [PMID: 36690654 PMCID: PMC9870880 DOI: 10.1038/s41598-023-28168-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 01/13/2023] [Indexed: 01/25/2023] Open
Abstract
We evaluated the variation in the frequency of benzimidazole (BZ) resistance-associated alleles at codons 200, 167 and 368 (F200Y, F167Y, V368L) of the β-tubulin isotype 1 gene during the patent period in isolates of Haemonchus contortus susceptible and resistant to BZ using pyrosequencing. Four lambs 5-6 months old were infected with 5000-6000 infective third-stage larvae (L3) of the susceptible MHco1 and the multi-resistant MHco4 isolates, respectively. Faecal samples were collected 28-times during 20-90 days post-infection (dpi). Coprocultures were subsequently prepared to produce L3 for genotyping. The frequency of the resistant allele (TAC) at codon 200 in MHco1 was lowest at 43 and 76 dpi with at each time point 0% and highest at 36 dpi with 10.85%, with a mean of 6.47% ± 2.39 and a coefficient of variation of 37.01%. The frequency of the TAC at codon 200 in MHco4 was lowest at 76 dpi with 25.6% and highest at 90 dpi with 49.25%, with a mean of 35.7% ± 4.42 and a coefficient of variation of 12.39%. No resistance alleles were detected in MHco1 at either codon 167 or 368. For MHco4 isolate, resistance alleles were detected only on codon 167 with a mean of 8.00% ± 4.83 and a mean coefficient of variation of 60.40%. Our results demonstrate the considerable variation in the frequency of resistant alleles in the susceptible and resistant isolates during the patent period. This variation should be considered when testing for the presence of BZ resistance in populations of gastrointestinal parasites, especially those with a low frequency of TAC.
Collapse
Affiliation(s)
- Michaela Urda Dolinská
- Institute of Parasitology of the Slovak Academy of Sciences, Hlinkova 3, 040 01, Košice, Slovakia
| | - Alžbeta Königová
- Institute of Parasitology of the Slovak Academy of Sciences, Hlinkova 3, 040 01, Košice, Slovakia
| | - Georg von Samson Himmelstjerna
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-Von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - Marián Várady
- Institute of Parasitology of the Slovak Academy of Sciences, Hlinkova 3, 040 01, Košice, Slovakia.
| |
Collapse
|
7
|
Signs of multiple anthelmintic resistance in sheep gastrointestinal nematodes in Sweden. Vet Parasitol Reg Stud Reports 2022; 36:100789. [PMID: 36436900 DOI: 10.1016/j.vprsr.2022.100789] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/31/2022] [Accepted: 09/27/2022] [Indexed: 01/14/2023]
Abstract
Gastrointestinal nematodes in small ruminants are clinically and economically important parasites that often are controlled with anthelmintics. In this study, we compiled information on the anthelmintic efficacy collected on sheep farms according to routines established by Farm & Animal Health in Sweden. The efficacies of benzimidazoles (i.e. albendazole or fenbendazole, n = 30), ivermectin (n = 47), levamisole (n = 2) or moxidectin (n = 2) were examined between 2015 and 2021 in 81 treatment groups on 49 non-randomly selected farms in south-central Sweden. Drug efficacies were estimated with the faecal egg count reduction test. In addition, efficacy data were in most cases supplemented with data on the abundance of the three most common nematode genera in sheep by performing droplet digital (dd) PCR on coprocultures. Efficacies of <95% for benzimidazoles or ivermectin were identified in 37% and 77% of the tested groups, respectively. In addition, on 27 (55%) of the 49 farms where both benzimidazoles and ivermectin were tested, multiple resistance was found on 8 (30%). In contrast, on each of the two farms tested for levamisole and moxidectin both drugs proved to be 100% effective. However, because post-sampling was performed earlier than recommended in several susceptible groups (benzimidazoles = 15, and ivermectin = 10 groups), this could have underestimated the severity of the situation. Mainly larvae from the genus Haemonchus were detected in post-treatment coprocultures, in all groups with declared resistance, suggesting that this parasite was primarily associated with anthelmintic resistance. Unexpectedly, the DNA of larvae, which survived treatment, was also detected on farms declared as susceptible. Taken together, this indicates that the situation regarding the anthelmintic efficacy has deteriorated compared with the latest nationwide study on Swedish sheep farms conducted more than a decade ago. Unlike the previous study, the farm selection here was not strictly randomized but rather opportunistic i.e., only farms with a recognized parasite problem were included. Thus, there is a need for a truly randomized study to get an update on the extent of the situation of anthelmintic resistance at a national level, as well as to identify risk factors involved in the resistance selection. Research is also required to establish the optimal intervals for sampling post-treatment.
Collapse
|
8
|
Moving beyond the state of the art of understanding resistance mechanisms in hookworms: confirming old and suggesting new associated SNPs. Acta Trop 2022; 233:106533. [PMID: 35598651 DOI: 10.1016/j.actatropica.2022.106533] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 04/04/2022] [Accepted: 05/18/2022] [Indexed: 11/23/2022]
Abstract
Hookworms represent a serious problem for human and animal health in different parts of the world. One of the suggested control strategies for parasitosis caused by members of the Ancylostomatidae family is mass drug aministration with benzimidazole compounds. This strategy has been proven to lead to the establishment of resistant strains in several nematodes related to SNPs at codons 167, 198 and 200 of the beta-tubulin isotype-1 gene. Through bioassay and in vivo analysis, we successfully isolated an albendazole-resistant A. ceylanicum strain by drug selective pressure. We observed a strong correlation between the presence of SNPs at codon 198 and drug resistance. We also described for the first time, in hookworms, the presence of SNP A200L, already described at low frequencies in ruminant nematodes. The results presented here are important for updating the current knowledge about anthelmintic resistance in hookworms. The answers and the new questions raised may provide a basis for the establishment of more effective control strategies.
Collapse
|
9
|
Absence of Polymorphisms in Codons 167, 198 and 200 of All Seven β-tubulin Isotypes of Benzimidazole Susceptible and Resistant Parascaris spp. Specimens from Australia. Pathogens 2022; 11:pathogens11050490. [PMID: 35631011 PMCID: PMC9143322 DOI: 10.3390/pathogens11050490] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 04/14/2022] [Accepted: 04/19/2022] [Indexed: 11/24/2022] Open
Abstract
Benzimidazoles resistance is widespread in strongyle parasitic nematodes and associated with polym orphisms in the codons 167, 198 and 200 of isotype 1 β-tubulin (tbb-1). In ascarids, benzimidazole (BZ) resistance has rarely been reported and in none of these cases were any of these polymorphisms detected. Here, available genome and transcriptome data from WormBase ParaSite were used to compare the complete β-tubulin reservoirs of Parascaris univalens, Ascaris suum and Ascaris lumbricoides. Adult Parascaris spp. specimens collected in Australia from horses after BZ treatment (susceptible, n = 13) or surviving BZ treatment and collected after ivermectin treatment (resistant, n = 10) were genotyped regarding codons 167, 198 and 200 using Sanger sequencing. Phylogenetic analyses clearly showed that there are no one-to-one ascarid orthologs of strongyle tbb-1 genes. In the reference genomes, as well as phenotypically susceptible and resistant Parascaris spp. from Australia, six out of seven β-tubulin genes showed a BZ-susceptible genotype (F167, E198, F200). The only exception were the testis-specific β-tubulin D genes from all three ascarid species that encode tyrosine at codon 200. This was observed independently of the BZ-susceptibility phenotype of Parascaris spp. These data suggest that different mechanisms lead to BZ resistance in ascarid and strongyle nematodes.
Collapse
|
10
|
Guo Y, Dong HY, Zhou HC, Zhang ZS, Zhao Y, Zhang YJ. Mechanism of the Passage of Angiostrongylus cantonensis across the Final Host Blood-Brain Barrier Using the Next-Generation Sequencing. IRANIAN JOURNAL OF PARASITOLOGY 2021; 16:454-463. [PMID: 34630591 PMCID: PMC8476730 DOI: 10.18502/ijpa.v16i3.7099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 04/09/2021] [Indexed: 11/24/2022]
Abstract
Background: Multicellular parasites Angiostrogylus cantonensis larvae develop in the final host rat brain at the fourth stage (L4) and migrate to the lungs by the adult stage. The potential mechanism of its blood-brain barrier (BBB) passage remains unclear. Methods: By using Illumina Hiseq/Miseq sequencing, we obtained the transcriptomes of 3 groups of adult males and 3 groups of female of A. cantonensis to generate similarly expressed genes (SEGs) between 2 genders at the adult stage. Next 2 groups of L4 expressed genes were used to compared with SEGs to create differentially expressed genes (DEGs) between 2 life stages to unlock potential mechanism of BBB passage. Results: In total, we obtained 381 581 802 clean reads and 56 990 699 010 clean bases. Of these, 331 803 unigenes and 482 056 transcripts were successfully annotated. A total of 3 166 DEGs between L4 and adults SEGs were detected. Annotation of these DEGs showed 167 were down-regulated and 181 were up-regulated. Pathway analysis exhibited that calcium signaling pathway, the ECM−receptor interaction, focal adhesion, and cysteine and methionine metabolism were highly associated with DEGs. The function of these pathways might be related to BBB traversal, as well as neuro-regulation, interactions between parasite and host, environmental adaption. Conclusion: This study expanded the regulatory characteristics of the two important life stages of A. cantonensis. This information may provide a better appreciation of the biological features of the stages of the parasitic A. cantonensis.
Collapse
Affiliation(s)
- Yue Guo
- School of Medicine, Huzhou University, Huzhou Cent Hosp, Zhejiang, China.,Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Hai Yan Dong
- School of Medicine, Huzhou University, Huzhou Cent Hosp, Zhejiang, China.,Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Hong Chang Zhou
- School of Medicine, Huzhou University, Huzhou Cent Hosp, Zhejiang, China.,Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou University, Huzhou, Zhejiang, China
| | - Zhong Shan Zhang
- School of Medicine, Huzhou University, Huzhou Cent Hosp, Zhejiang, China.,School of Life Sciences, Huzhou University, Zhejiang, China
| | - Yu Zhao
- School of Medicine, Huzhou University, Huzhou Cent Hosp, Zhejiang, China
| | - Yu Jie Zhang
- School of Medicine, Huzhou University, Huzhou Cent Hosp, Zhejiang, China
| |
Collapse
|
11
|
Martin F, Halvarsson P, Delhomme N, Höglund J, Tydén E. Exploring the β-tubulin gene family in a benzimidazole-resistant Parascaris univalens population. Int J Parasitol Drugs Drug Resist 2021; 17:84-91. [PMID: 34467878 PMCID: PMC8406161 DOI: 10.1016/j.ijpddr.2021.08.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/15/2021] [Accepted: 08/19/2021] [Indexed: 12/15/2022]
Abstract
Benzimidazole (BZ) drugs are frequently used to treat infections with the equine ascarid Parascaris univalens due to increasing resistance to macrocyclic lactones and pyrantel. Benzimidazole resistance is rare in ascarids in contrast to strongyle parasites where this resistance is widespread. In strongyles, single nucleotide polymorphisms (SNPs) at codons 167, 198 and 200 in a β-tubulin gene have been correlated to BZ resistance, but little is known about the β-tubulin genes and their possible involvement in BZ resistance in P. univalens and other ascarids. Previously two β-tubulin genes have been identified in P. univalens. In this study, we present five additional β-tubulin genes as well as the phylogenetic relationship of all seven genes to β-tubulins of other clade III and V nematodes. In addition, the efficacy of fenbendazole for treatment of P. univalens on a Swedish stud farm was studied in 2019 and 2020 using faecal egg count reduction test. Reductions varied from 73% to 88%, indicating the presence of a resistant P. univalens population on the farm. The emergence of BZ resistance emphasizes the need for development of molecular markers for rapid and more sensitive detection of resistant populations. We therefore investigated whether possible SNPs at positions 167, 198 or 200 in any of the β-tubulin genes could be used to distinguish between resistant and susceptible P. univalens populations. Amplicon sequencing covering the mutation sites 167, 198 and 200 in all seven β-tubulin genes revealed an absence of SNPs in both resistant and susceptible populations, suggesting that the mechanism behind BZ resistance in ascarids is different from that in strongyle nematodes and the search for a molecular marker for BZ resistance in P. univalens needs to continue. First case of fenbendazole resistance in Parascaris univalens in Europe. The P. univalens β-tubulin family contains seven genes. P. univalens β-tubulin genes cluster with β-tubulins from other clade V nematodes. No resistance associated SNPs were identified in P. univalens β-tubulin genes.
Collapse
Affiliation(s)
- Frida Martin
- Swedish University of Agricultural Sciences, Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Box 7036, 750 07, Uppsala, Sweden.
| | - Peter Halvarsson
- Swedish University of Agricultural Sciences, Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Box 7036, 750 07, Uppsala, Sweden
| | - Nicolas Delhomme
- Umeå Plant Science Centre (UPSC), Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 901 83, Umeå, Sweden
| | - Johan Höglund
- Swedish University of Agricultural Sciences, Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Box 7036, 750 07, Uppsala, Sweden
| | - Eva Tydén
- Swedish University of Agricultural Sciences, Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Box 7036, 750 07, Uppsala, Sweden
| |
Collapse
|
12
|
Garge RK, Cha HJ, Lee C, Gollihar JD, Kachroo AH, Wallingford JB, Marcotte EM. Discovery of new vascular disrupting agents based on evolutionarily conserved drug action, pesticide resistance mutations, and humanized yeast. Genetics 2021; 219:iyab101. [PMID: 34849907 PMCID: PMC8633126 DOI: 10.1093/genetics/iyab101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 06/15/2021] [Indexed: 12/20/2022] Open
Abstract
Thiabendazole (TBZ) is an FDA-approved benzimidazole widely used for its antifungal and antihelminthic properties. We showed previously that TBZ is also a potent vascular disrupting agent and inhibits angiogenesis at the tissue level by dissociating vascular endothelial cells in newly formed blood vessels. Here, we uncover TBZ's molecular target and mechanism of action. Using human cell culture, molecular modeling, and humanized yeast, we find that TBZ selectively targets only 1 of 9 human β-tubulin isotypes (TUBB8) to specifically disrupt endothelial cell microtubules. By leveraging epidemiological pesticide resistance data and mining chemical features of commercially used benzimidazoles, we discover that a broader class of benzimidazole compounds, in extensive use for 50 years, also potently disrupt immature blood vessels and inhibit angiogenesis. Thus, besides identifying the molecular mechanism of benzimidazole-mediated vascular disruption, this study presents evidence relevant to the widespread use of these compounds while offering potential new clinical applications.
Collapse
Affiliation(s)
- Riddhiman K Garge
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Hye Ji Cha
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- Division of Hematology/Oncology, Boston Children's Hospital and Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Chanjae Lee
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Jimmy D Gollihar
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
- US Army Research Laboratory—South, Austin, TX 78758, USA
| | - Aashiq H Kachroo
- The Department of Biology, Centre for Applied Synthetic Biology, Concordia University, Montreal, QC H4B 1R6, Canada
| | - John B Wallingford
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Edward M Marcotte
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA
| |
Collapse
|
13
|
Costa-Junior LM, Chaudhry UN, Skuce PJ, Stack S, Sargison ND. A loop-mediated isothermal amplification (LAMP) assay to identify isotype 1 β-tubulin locus SNPs in synthetic double-stranded Haemonchus contortus DNA. J Parasit Dis 2021; 46:47-55. [PMID: 35295940 PMCID: PMC8901900 DOI: 10.1007/s12639-021-01414-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/21/2021] [Indexed: 11/27/2022] Open
Abstract
Development of sustainable gastrointestinal nematode (GIN) control strategies depends on the ability to identify the frequencies of drug-susceptible and resistant genotypes in GIN populations arising from management practices undertaken on individual farms. Resistance to BZ drugs in GINs has been shown to be conferred by the presence of defined SNPs in the isotype 1 β-tubulin locus. Loop-mediated isothermal amplification (LAMP) assays are amenable to use on a range of DNA templates and are potentially adaptable to use in practical, cost-effective, pen-side diagnostic platforms that are needed to detect anthelmintic resistance in the field. In this study, we designed primers and examined LAMP assays to detect each of the three major isotype 1 β-tubulin SNPs conferring genetic susceptibility to BZ drugs. We used artificial pools of synthetic DNA, containing different proportions of susceptible and resistant SNPs to determine reproducibility of the assays. We demonstrated the detection of each of the isotype 1 β-tubulin SNPs conferring susceptibility to BZ drugs using the optimal LAMP assay. Isotype 1 β-tubulin SNP typing was effective in detecting BZ susceptibility, but the accuracy was reduced in samples with less than 60 % susceptible DNA. Our results show the potential for LAMP SNP typing to detect genetic susceptibility or resistance to anthelmintic drugs in livestock GINs, and some of the limitations in our approach that will need to be overcome in order to evaluate this assay using field samples.
Collapse
Affiliation(s)
| | - Umer N. Chaudhry
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG UK
| | - Philip J. Skuce
- Moredun Research Institute, Pentlands Science Park, Edinburgh, Midlothian, EH26 0PZ Scotland, UK
| | - Seamus Stack
- Mast Group, Mast House, Derby Road, Bootle Merseyside, L20 1EA UK
| | - Neil D. Sargison
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, EH25 9RG UK
| |
Collapse
|
14
|
Baltrušis P, Charvet CL, Halvarsson P, Mikko S, Höglund J. Using droplet digital PCR for the detection of hco-acr-8b levamisole resistance marker in H. contortus. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2021; 15:168-176. [PMID: 33799059 PMCID: PMC8044644 DOI: 10.1016/j.ijpddr.2021.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/16/2021] [Accepted: 03/16/2021] [Indexed: 11/19/2022]
Abstract
The nematode Haemonchus contortus is one of the most prevalent and pathogenic parasites in small ruminants. Although usually controlled using anthelmintics, the development of drug resistance by the parasite has become a major issue in livestock production. While the molecular detection of benzimidazole resistance in H. contortus is well developed, the molecular tools and protocols are far less advanced for the detection of levamisole resistance. The hco-acr-8 gene encodes a critical acetylcholine susceptible subunit that confers levamisole-sensitivity to the receptor. Here, we report the development of a droplet digital PCR assay as a molecular tool to detect a 63 bp deletion in the hco-acr-8 that has been previously associated with levamisole resistance. Sanger sequencing of single adult H. contortus yielded 56 high-quality consensus sequences surrounding the region containing the deletion. Based on the sequencing data, new primers and probes were designed and validated with a novel droplet digital PCR assay for the quantification of the deletion containing “resistant” allele in genomic DNA samples. Single adult worms from six phenotypically described isolates (n = 60) and from two Swedish sheep farms (n = 30) where levamisole was effective were tested. Even though a significant difference in genotype frequencies between the resistant and susceptible reference isolates was found (p = 0.01), the homozygous “resistant” genotype was observed to be abundantly present in both the susceptible isolates as well as in some Swedish H. contortus samples. Furthermore, field larval culture samples, collected pre- (n = 7) and post- (n = 6) levamisole treatment on seven Swedish sheep farms where levamisole was fully efficacious according to Fecal Egg Count Reduction Test results, were tested to evaluate the frequency of the “resistant” allele in each. Frequencies of the deletion ranged from 35 to 80% in the pre-treatment samples, whereas no amplifiable H. contortus genomic DNA was detected in the post-treatment samples. Together, these data reveal relatively high frequencies of the 63 bp deletion in the hco-acr-8 both on individual H. contortus and field larval culture scales, and cast doubt on the utility of the deletion in the hco-acr-8 as a molecular marker for levamisole resistance detection on sheep farms. Acr8b – levamisole resistance marker investigated in single worms and larval cultures. Individuals homozygous for acr8b found more commonly, even in susceptible isolates. Levamisole treatment efficacy was unaffected by increased acr8b frequencies in larvae.
Collapse
Affiliation(s)
- Paulius Baltrušis
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| | | | - Peter Halvarsson
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Sofia Mikko
- Department of Animal Breeding & Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Johan Höglund
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| |
Collapse
|
15
|
Mohammedsalih KM, Krücken J, Bashar A, Juma FR, Abdalmalaik AAH, Khalafalla A, Abakar A, Coles G, von Samson-Himmelstjerna G. Susceptible trichostrongyloid species mask presence of benzimidazole-resistant Haemonchus contortus in cattle. Parasit Vectors 2021; 14:101. [PMID: 33557939 PMCID: PMC7869217 DOI: 10.1186/s13071-021-04593-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 01/11/2021] [Indexed: 11/25/2022] Open
Abstract
Background Benzimidazole (BZ) anthelmintics are widely used to control infections with parasitic nematodes, but BZ resistance is an emerging threat among several nematode species infecting humans and animals. In Sudan, BZ-resistant Haemonchus contortus populations were recently reported in goats in South Darfur State. The objective of this study was to collect data regarding the situation of BZ resistance in cattle parasitic nematodes in South Darfur using phenotypic and molecular approaches, besides providing some epidemiological data on nematodes in cattle. Methods The faecal egg count reduction test and the egg hatch test (EHT) were used to evaluate benzimidazole efficacy in cattle nematodes in five South Darfur study areas: Beleil, Kass, Nyala, Rehed Al-Birdi and Tulus. Genomic DNA was extracted from pools of third-stage larvae (L3) (n = 40) during trials, before and after treatment, and pools of adult male Haemonchus spp. (n = 18) from abattoirs. The polymorphisms F167Y, E198A and F200Y in isotype 1 β-tubulin genes of H. contortus and H. placei were analysed using Sanger and pyrosequencing. Results Prevalence of gastro-intestinal helminths in cattle was 71% (313/443). Reduced albendazole faecal egg count reduction efficacy was detected in three study areas: Nyala (93.7%), Rehed Al-Birdi (89.7%) and Tulus (88.2%). In the EHT, EC50 values of these study areas ranged between 0.032 and 0.037 µg/ml thiabendazole. Genus-specific PCRs detected the genera Haemonchus, Trichostrongylus and Cooperia in L3 samples collected after albendazole treatment. Sanger sequencing followed by pyrosequencing assays did not detect elevated frequencies of known BZ resistance-associated alleles in codon F167Y, E198A and F200Y in isotype 1 β-tubulin gene of H. placei (≤ 11.38%). However, polymorphisms were detected in H. contortus and in samples with mixed infections with H. contortus and H. placei at codon 198, including E198L (16/58), E198V (2/58) and potentially E198Stop (1/58). All pooled L3 samples post-albendazole treatment (n = 13) were identified as H. contortus with an E198L substitution at codon 198. Conclusions To the knowledge of the authors, this is the first report of reduced albendazole efficacy in cattle in Sudan and is the first study describing an E198L substitution in phenotypically BZ-resistant nematodes collected from cattle.![]()
Collapse
Affiliation(s)
| | - Jürgen Krücken
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Street 7-13, 14163, Berlin, Germany
| | - Ahmed Bashar
- Faculty of Veterinary Science, University of Nyala, P.O. Box 155, Nyala, Sudan
| | - Fathel-Rahman Juma
- Faculty of Veterinary Science, University of Nyala, P.O. Box 155, Nyala, Sudan
| | | | - Amna Khalafalla
- Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Adam Abakar
- Faculty of Medical Laboratory Sciences, University of Gezira, P.O. Box 20, Wadmedani, Sudan
| | - Gerald Coles
- Ubley Biologics, Ubley, P.O. Box 170, Bristol, BS40 6JA, UK
| | - Georg von Samson-Himmelstjerna
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Street 7-13, 14163, Berlin, Germany.
| |
Collapse
|
16
|
Yu Z, Zhao Z, Chen L, Li J, Ju X. Development of a Droplet Digital PCR for Detection of Trichuriasis in Sheep. J Parasitol 2021; 106:603-610. [PMID: 32997756 DOI: 10.1645/20-16] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Trichuriasis is a serious threat to the economic development of animal husbandry. This research aimed to establish a droplet digital PCR (ddPCR) method to detect Trichuris spp. for the early diagnosis and prevention of trichuriasis in sheep. The real-time quantitative PCR (qPCR) and ddPCR methods were used for the detection of nematodes by targeted amplification of the ITS gene. Each means was evaluated to optimize the limit of detection and reproducibility. For a recombinant plasmid, the qPCR results showed that the detection limit was 31.7 copies per reaction. In contrast to qPCR, ddPCR was able to detect concentrations below 3.17 copies per reaction. Both assays exhibited good reproducibility. However, the ddPCR method was more stable for low-copy-number detection. This new assay was specific for Trichuris spp. and did not cross-react with other relevant gastrointestinal nematodes. A total of 98 clinical samples were tested with both assays. The results showed that the positive rate of ddPCR (80.6%) was higher than that of qPCR (72.4%). This method could be used as an efficient molecular biology tool to test for Trichuris spp. and could be a new valuable tool for the clinical diagnosis and prevention of trichuriasis.
Collapse
Affiliation(s)
- Zhichao Yu
- Department of Veterinary Medicine, College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, Guangdong, China.,Technology Center, Hohhot Customs District, Hohhot, 010020, Inner Mongolia, China
| | - Zhiguo Zhao
- Technology Center, Hohhot Customs District, Hohhot, 010020, Inner Mongolia, China
| | - Linjun Chen
- Technology Center, Hohhot Customs District, Hohhot, 010020, Inner Mongolia, China
| | - Junyan Li
- Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot, 010031, China
| | - Xianghong Ju
- Department of Veterinary Medicine, College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang, 524088, Guangdong, China
| |
Collapse
|
17
|
Baltrušis P, Halvarsson P, Höglund J. Utilization of droplet digital PCR to survey resistance associated polymorphisms in the β tubulin gene of Haemonchus contortus in sheep flocks in Sweden. Vet Parasitol 2020; 288:109278. [DOI: 10.1016/j.vetpar.2020.109278] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 02/01/2023]
|
18
|
Fávero FC, Dos Santos LB, Araújo FRD, Ramünke S, Krücken J, von Samson-Himmelstjerna G, Borges FDA. Haemonchus sp. in beef cattle in Brazil: species composition and frequency of benzimidazole resistance alleles. Prev Vet Med 2020; 185:105162. [PMID: 33099153 DOI: 10.1016/j.prevetmed.2020.105162] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 09/23/2020] [Accepted: 09/24/2020] [Indexed: 02/06/2023]
Abstract
The aim of the present study was to investigate the occurrence of Haemonchus contortus and Haemonchus placei in beef cattle and the frequency of single nucleotide polymorphisms associated with benzimidazole (BZ)-resistance in Haemonchus spp. in Brazil. For such, fecal samples were collected from 61 beef cattle ranches in 11 Brazilian states. Third-stage larvae (L3) were produced for morphological species identification and DNA extraction. PCR was performed for the analysis of the isotype 1 β-tubulin gene and the products were sequenced to confirm the presence of H. placei and H. contortus. For each field population, pyrosequencing assays were performed to quantify the frequency of the F167Y, E198A and F200Y polymorphisms in the isotype-1 β-tubulin gene. The results of the morphometric analysis of 2345 larvae showed that H. placei was present on all ranches. The analysis of the isotype 1 β-tubulin gene confirmed 100% prevalence for H. placei and 23.7% for H. contortus. Pyrosequencing assays demonstrated single-nucleotide polymorphisms (SNPs) associated with BZ-resistance in all three codons (F167Y, E198A and F200Y) of the isotype 1 β-tubulin gene in H. placei field populations. Frequencies of resistance-associated alleles above background (≥ 15%) were found for at least one codon in 11.4% of the field isolates and maximum frequencies of 30, 21 and 29% were found for codons 167, 198 and 200, respectively, on individual ranches. This study confirms the presence of H. contortus in beef cattle in the major livestock farming states in Brazil and demonstrates that genotypes associated with BZ resistance are present in field populations of Haemonchus spp..
Collapse
Affiliation(s)
- Flávia C Fávero
- School of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
| | - Larissa B Dos Santos
- School of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, Brazil
| | - Flábio R de Araújo
- Brazilian Agricultural Research Corporation, Embrapa Gado de Corte, Campo Grande, Brazil
| | - Sabrina Ramünke
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Jürgen Krücken
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | | | - Fernando de A Borges
- School of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, Brazil.
| |
Collapse
|
19
|
Assessment of the F200Y mutation frequency in the β tubulin gene of Haemonchus contortus following the exposure to a discriminating concentration of thiabendazole in the egg hatch test. Exp Parasitol 2020; 217:107957. [PMID: 32687847 DOI: 10.1016/j.exppara.2020.107957] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/24/2020] [Accepted: 07/13/2020] [Indexed: 02/01/2023]
Abstract
The ruminant livestock production sector is under threat due to the infections with gastrointestinal nematode parasites and the subsequent development of anthelmintic resistance. One of most common and pathogenic species in small ruminants is Haemonchus contortus. The ability to control the infections with this and other gastrointestinal nematodes relies heavily on the use of anthelmintic drugs. Although resistance to all major classes of anthelmintics has been shown in H. contortus, the precise mechanism of resistance acquisition is only known for benzimidazoles. F200Y (TAC) is a common point mutation in the isotype 1 β tubulin gene which is associated with an effective increase in the resistance towards benzimidazole drugs. Here, we show the utility of using this mutation as a marker in a droplet digital PCR assay to track how two H. contortus laboratory strains, characterized by different resistance levels, change with respect to this mutation, when subjected to increasing concentrations of thiabendazole. Additionally, we wanted to investigate whether exposure to a discriminating dose of thiabendazole in the egg hatch test resulted in the death of all H. contortus eggs with a susceptible genotype. We found the MHco5 strain to maintain an overall higher frequency of the F200Y mutation (80-100%) over all drug concentrations, whilst a steady, gradual increase from around 30%-60% was observed in the case of the MHco4 strain. This is further supported by the dose-response curves, displaying a much higher tolerance of the MHco5 strain (LD50 = 0.38 μg/ml) in comparison to the MHco4 strain (LD50 = 0.07 μg/ml) to the effects of thiabendazole. All things considered, we show that the F200Y mutation is still a viable and reliable marker for the detection and surveillance of benzimidazole drug resistance in H. contortus in Europe.
Collapse
|
20
|
Mohammedsalih KM, Krücken J, Khalafalla A, Bashar A, Juma FR, Abakar A, Abdalmalaik AAH, Coles G, von Samson-Himmelstjerna G. New codon 198 β-tubulin polymorphisms in highly benzimidazole resistant Haemonchus contortus from goats in three different states in Sudan. Parasit Vectors 2020; 13:114. [PMID: 32122383 PMCID: PMC7053126 DOI: 10.1186/s13071-020-3978-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 02/17/2020] [Indexed: 01/12/2023] Open
Abstract
Background Benzimidazole (BZ) resistance in gastrointestinal nematodes is a worldwide problem for livestock production, particularly in small ruminants. Assignment of the emergence of resistance using sensitive and reliable methods is required to adopt the correct strategies for control. In Sudan, BZ resistant Haemonchus contortus populations were recently reported in goats in South Darfur. This study aimed to provide additional data regarding albendazole efficacy and to describe the prevailing molecular BZ resistance mechanisms. Methods Faecal egg count reduction and egg hatch tests (EHT) were used to evaluate albendazole efficacy in three different areas of South Darfur using naturally (Rehed Al-Birdi and Tulus) and experimentally infected (Tulus and Um Dafuq) goats. Using samples from Central, East and South Darfur, pyro- and Sanger sequencing were used to detect the polymorphisms F167Y, E198A and F200Y in H. contortus isotype 1 β-tubulin in DNA extracted from pooled third-stage larval (L3) samples (n = 36) on days 0 and 10 during trials, and from pooled adult male H. contortus (treated goats, n = 14; abattoirs, n = 83) including samples from populations previously found to be resistant in South Darfur. Results Albendazole efficacies at 5, 7.5 and 10 mg/kg doses were 73.5–90.2% on day 14 in natural and experimental infections while 12.5 mg/kg showed > 96.6% efficacy. EC50 in the EHT were 0.8 and 0.11 µg/ml thiabendazole in natural and experimental infection trials, respectively. PCRs detected Haemonchus, Trichostrongylus and Cooperia in L3 samples from albendazole-treated goats. Haemonchus contortus allele frequencies in codons 167 and 200 using pyrosequencing assays were ≤ 7.4% while codon 198 assays failed. Sanger sequencing revealed five novel polymorphisms at codon 198. Noteworthy, an E198L substitution was present in 82% of the samples (L3 and adults) including all post-treatment samples. Moreover, E198V, E198K and potentially E198I, and E198Stop were identified in a few samples. Conclusions To our knowledge, this is the first report of E198L in BZ resistant H. contortus and the second where this is the predominant genotype associated with resistance in any strongyle species. Since this variant cannot be quantified using pyrosequencing, the results highlight important limitations in the general applicability of pyrosequencing to quantify BZ resistance genotypes.![]()
Collapse
Affiliation(s)
| | - Jürgen Krücken
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| | - Amna Khalafalla
- Faculty of Veterinary Medicine, University of Khartoum, PO Box 32, Khartoum North, Sudan
| | - Ahmed Bashar
- Faculty of Veterinary Science, University of Nyala, Nyala, Sudan
| | | | - Adam Abakar
- Faculty of Medical Laboratory Sciences, University of Gezira, PO Box 20, Wad Medani, Sudan
| | | | - Gerald Coles
- Ubley Biologics, PO Box 170, Ubley, Bristol, BS40 6JA, UK
| | - Georg von Samson-Himmelstjerna
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163, Berlin, Germany
| |
Collapse
|
21
|
Furtado LFV, Medeiros CDS, Zuccherato LW, Alves WP, de Oliveira VNGM, da Silva VJ, Miranda GS, Fujiwara RT, Rabelo ÉML. First identification of the benzimidazole resistance-associated F200Y SNP in the beta-tubulin gene in Ascaris lumbricoides. PLoS One 2019; 14:e0224108. [PMID: 31622428 PMCID: PMC6797262 DOI: 10.1371/journal.pone.0224108] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 10/04/2019] [Indexed: 01/07/2023] Open
Abstract
The main control strategy for Ascaris lumbricoides is mass drug administration (especially with benzimidazoles), which can select strains of parasites resistant to treatment. Mutations in the beta-tubulin isotype-1 gene at codons 167, 198 and 200 have been linked to benzimidazole resistance in several nematodes. The mutation in codon 200 is the most frequent in different species of parasites, as previously observed in Necator americanus and Trichuris trichiura; however, this mutation has never been found in populations of A. lumbricoides. This study aimed to screen for single nucleotide polymorphisms (SNPs) in the beta-tubulin isotype-1 gene at codon 200 in A. lumbricoides. We developed a technique based on an amplification refractory mutation system (ARMS-PCR) for the analysis of 854 single A. lumbricoides eggs collected from 68 human stool samples from seven Brazilian states. We detected the mutation in codon 200 at a frequency of 0.5% (4/854). This is the first report of this mutation in A. lumbricoides. Although the observed frequency is low, its presence indicates that these parasite populations have the potential to develop high levels of resistance in the future. The methodology proposed here provides a powerful tool to screen for the emergence of anthelmintic resistance mutations in parasitic nematode populations.
Collapse
Affiliation(s)
| | - Celi da Silva Medeiros
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Luciana Werneck Zuccherato
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - William Pereira Alves
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Vivian Jordania da Silva
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Guilherme Silva Miranda
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Ricardo Toshio Fujiwara
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Élida Mara Leite Rabelo
- Departamento de Parasitologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| |
Collapse
|
22
|
Baltrušis P, Halvarsson P, Höglund J. Molecular detection of two major gastrointestinal parasite genera in cattle using a novel droplet digital PCR approach. Parasitol Res 2019; 118:2901-2907. [PMID: 31388787 PMCID: PMC6754349 DOI: 10.1007/s00436-019-06414-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 07/26/2019] [Indexed: 01/25/2023]
Abstract
Cooperia sp. and Ostertagia sp. are two cosmopolitan parasitic nematodes often found in mixed gastrointestinal infections in cattle across temperate regions. In light of the recent increase in the emergence of anthelmintic resistance in these and other nematodes derived from cattle around the globe, and their negative impact on animal health and productivity, novel molecular assays need to be put forth in order to facilitate the monitoring of parasite burden in infected herds, using pasture and/or fecal samples. Here, we describe a novel droplet digital PCR platform–based concept for precise identification and quantification of the two most abundant and important parasite genera in grazing western European cattle. By exploiting a single nucleotide difference in the two parasites’ ITS2 sequence regions, we have developed two specific hydrolysis probes labeled with FAM™ or HEX™ fluorophores, which can not only distinguish between the DNA sequences of the two, but also quantify them in mixed DNA samples. A third, newly developed universal probe was also tested along the genus-specific probes to provide a robust and accurate reference. It was evident that the universal probe displayed congruent results to those obtained by the genus-specific probes when used with DNA from both parasites in a single sample. All in all, the results of our assay suggest that this novel protocol could be used to distinguish and quantify cattle parasites belonging to the two most important genera (i.e., Cooperia and Ostertagia) in a single mixed DNA sample.
Collapse
Affiliation(s)
- Paulius Baltrušis
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, P.O. Box 7036, Uppsala, Sweden.
| | - Peter Halvarsson
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, P.O. Box 7036, Uppsala, Sweden
| | - Johan Höglund
- Department of Biomedical Sciences and Veterinary Public Health, Section for Parasitology, Swedish University of Agricultural Sciences, P.O. Box 7036, Uppsala, Sweden
| |
Collapse
|