Frequency of benzimidazole resistance inHaemonchus contortus populations isolated from buffalo, goat and sheep herds

Anthelmintic resistance is an increasing problem that threatens livestock production worldwide. Understanding of the genetic basis of benzimidazole resistance recently allowed the development of promising molecular diagnostic tools. In this study, isolates of Haemonchus contortus obtained from goats, sheep and buffaloes raised in Brazil were screened for presence of the polymorphism Phe200Tyr in the β-tubulin 1 gene, which confers resistance to benzimidazole. The allelic frequency of the mutation conferring resistance ranged from 7% to 43%, and indicated that resistance to benzimidazole could be found in nematodes isolated from all the ruminant species surveyed. Although significant variation in the frequency of the F200Y mutation was observed between different herds or host species, no significant variation could be found in populations isolated from animals within the same herd. These findings suggest that screening of samples from a few animals has the potential to provide information about the benzimidazole resistance status of the entire herd, which would enable a considerable reduction in the costs of diagnosis for the producer. Molecular diagnosis has practical advantages, since it can guide the choice of anthelmintic drug that will be used, before its application in the herd, thus reducing the economic losses driven by anthelmintic resistance.

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Comparison of two in vitro methods for the detection of ivermectin resistance in Haemonchus contortus in sheep

Helminthologia ◽

10.1515/helmin-2015-0002 ◽

2016 ◽

Vol 53 (2) ◽

pp. 120-125 ◽

Cited By ~ 2

Author(s):

M. Urda Dolinská ◽

A. Königová ◽

M. Babják ◽

M. Várady

Keyword(s):

Drug Resistance ◽

Haemonchus Contortus ◽

Anthelmintic Resistance ◽

Economic Losses ◽

Parasitic Nematodes ◽

Migration Inhibition ◽

In Vitro Methods ◽

Parasitic Helminths

SummaryGastrointestinal parasitic nematodes in sheep cause severe economic losses. Anthelmintics are the most commonly used drugs for prophylaxis and therapy against parasitic helminths. The problem of drug resistance has developed for all commercially available anthelmintics in several genera and classes of helminths. In vitro and in vivo tests are used to detect anthelmintic resistance. Two in vitro methods (larval migration inhibition test and micromotility test) for the detection of ivermectin (IVM) resistance were compared using IVM-resistant and IVM-susceptible isolates of Haemonchus contortus. The degree of resistance for each test was expressed as a resistance factor (RF). The micromotility test was more sensitive for quantitatively measuring the degree of resistance between susceptible and resistant isolates. The RFs for this test for IVM and eprinomectin ranged from 1.00 to 108.05 and from 3.87 to 32.32, respectively.

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Molecular Detection of Benzimidazole Resistance in Haemonchus contortus Larvae of Goats in Chhattisgarh, India

Indian Journal of Animal Research ◽

10.18805/ijar.b-4532 ◽

2021 ◽

Author(s):

S. Nath ◽

S. Pal ◽

S. Mandal ◽

S. Jadhao ◽

M. Sankar ◽

...

Keyword(s):

Nested Pcr ◽

Haemonchus Contortus ◽

Central India ◽

Allelic Frequency ◽

Specific Pcr ◽

Benzimidazole Resistance ◽

Pcr Product ◽

Pcr Rflp ◽

Allele Specific ◽

Homozygous Resistant

Background: Benzimidazole resistance is one of the key problem in small ruminant production. A rapid, truthful and responsive system is required for detection benzimidazole resistance so that proper regulatory measure can be applied. Allele specific PCR is one of the tools to understand the mechanism and origin of benzimidazole resistance. Methods: A total 198 larvae of Haemonchus contortus were isolated from goats of Chhattisgarh region, central India were genotyped by allele specific polymerase chain reaction (AS-PCR). Faecal samples of goats were collected from three Government farms and adjoining field goats and were subjected for faecal culture, separately. DNA of third stage larva was used for nested PCR for amplification of β- tubulin gene. Restriction Fragment Length Polymorphism (RFLP) was applied on nested PCR product for species identification with RsaI enzyme. AS-PCR was applied on the nested-PCR product to know the genotypic and allelic frequency. Result: The nested PCR amplified product showed approximately 820 bp in all cases and PCR-RFLP revealed 462 bp, 211 bp and 147 bp fragments, which confirmed the species as H. Contortus. Frequency of resistant allele ('r') was 49.7% and 50.3% for susceptible allele ('S '). Frequency of homozygous resistant (rr), heterozygous susceptible (rS) and homozygous susceptible (SS) genotype were 33.83 per cent, 31.81 per cent and 34.34 per cent, respectively. The frequency of homozygous resistant (rr) genotype was low (19.61%) in field compare to farm (48.96%) indicating refugia in field region.

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Patterns of infection, origins and transmission of ranaviruses among the ectothermic vertebrates of Asia

10.22541/au.162257077.70297443/v1 ◽

2021 ◽

Author(s):

Jayampathi Herath ◽

Gajaba Ellepola ◽

Madhava Meegaskumbura

Keyword(s):

Native Species ◽

Global Climate ◽

Significant Risk ◽

Molecular Diagnostic ◽

Economic Losses ◽

Diagnostic Tools ◽

Broad Host Range ◽

Host Taxon ◽

Pathogen Screening ◽

Means Of Transmission

Ranaviral infections, a malady of ectothermic vertebrates, are becoming frequent, severe, and widespread, causing mortality among both native and cultured species, raising odds of species extinctions and economic losses. This turn of events is possibly due to the broad host range of ranaviruses and the transmission of these pathogens through regional and international trade in Asia, where outbreaks have been increasingly reported over the past decade. Here we focus attention on the origins, means of transmission, and patterns of spread of this infection within the region. Infections have been recorded in both cultured and wild populations in at least twelve countries/administrative regions, together with mass die-offs in some regions. Despite the imminent seriousness of the disease in Asia, surveillance efforts are still incipient. Some of the infections transmitted within Asia may transmit across host-taxon barriers, posing a significant risk to native species. Factors such as rising temperatures due to global climate change seem to exacerbate ranaviral activity, as most known outbreaks have been recorded during summer; however, data are still inadequate to verify this for Asia. Import risk analysis, using protocols such as Pandora+, pre-border pathogen screening, and effective biosecurity measures, can be used to mitigate introduction to uninfected areas and curb transmission within Asia. Comprehensive surveillance using molecular diagnostic tools for ranavirus species and variants will help in understanding the prevalence and disease burden in the region. This is an important step towards conserving native biodiversity and safeguarding the aquaculture industry.

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PSIV-9 Effects of plant extracts on adult Haemonchus contortus mortality

Journal of Animal Science ◽

10.1093/jas/skz258.458 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 225-225

Author(s):

Trixie L Wetmore ◽

Taylor Luce ◽

Ken Mix ◽

Elizabeth Benavides

Keyword(s):

Plant Extracts ◽

Haemonchus Contortus ◽

Seed Oil ◽

Anthelmintic Resistance ◽

Anthelmintic Activity ◽

Negative Control ◽

Economic Losses ◽

Pumpkin Seed ◽

Time To Death ◽

Pumpkin Seed Oil

Abstract Parasitic infections are a major concern in animal production with global control measures costing over $10 billion annually. In small ruminants, Haemonchus contortus contributes to substantial economic losses in weight gain and mortality. Historical pharmaceutical control of H. contortus resulted in anthelmintic resistance, further exacerbating economic losses. The rise of anthelmintic resistance precipitated the need to investigate alternative treatments. One promising area is using anthelmintically active plant extracts. It is hypothesized that substances extracted from pumpkin seeds, garlic, and wormwood will demonstrate anthelmintic activity against H. contortus. The objective of this study was to evaluate the effects of three plant extracts on adult H. contortus mortality in vitro. Pumpkin seed oil (extracted from Cucurbita maxima), allicin (extracted from Allium sativum), and artemisinin (extracted from Artemisia absinthium) were selected as viable alternatives and evaluated for anthelmintic activity. Live adult H. contortus nematodes were extracted from the abomasum of sheep and goats collected from a local abattoir and placed in triplicate into 6-well plates containing differing concentrations of treatments. Fenbendazole was utilized as a positive control and physiological saline as a negative control. Anthelmintic efficacy was determined via time-to-death observation. Time-to-death was determined hourly by observation of movement for thirty seconds. Absence of movement for thirty seconds indicated death. Time-to-death was evaluated via ANOVA. Allicin exhibited a time-to-death similar to fenbendazole (2.15 ± 0.58 h vs. 1.00 ± 0.58 h, P = 0.15). Pumpkin seed oil exhibited accelerated time-to-death compared to negative control (4.15 ± 0.73 h vs. 10.00 ± 0.73 h, P < 0.01). Artemisin did not affect time-to-death at the tested concentrations. Allicin and pumpkin seed oil demonstrated potential as alternative anthelmintics at the evaluated concentrations, providing a potential treatment for H. contortus. Further investigation will determine synergistic effects between extracts and pharmaceuticals.

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Effect of Jatropha curcas Latex on L3 Haemonchus contortus Larval Motility

International Journal of Pharmaceutical and Clinical Research ◽

10.25258/ijpcr.v9i3.8317 ◽

2017 ◽

Vol 9 (3) ◽

Cited By ~ 1

Author(s):

Noorzaid Muhamad ◽

Syahirah Sazeli ◽

Resni Mona ◽

Jannathul Firdous

Keyword(s):

Larvicidal Activity ◽

Jatropha Curcas ◽

Haemonchus Contortus ◽

Anthelmintic Resistance ◽

Small Ruminants ◽

Gastrointestinal Nematodes ◽

Dose Dependent ◽

Plants Extract

The anthelmintic resistance has limited the control of gastrointestinal nematodes of small ruminants and thus has awakened interest in the study of plants extract as a source of anthelmintics. These experiments were carried out to evaluate the in vitro efficacy of Jatrophacurcas latex extract against Haemonchuscontortus larval motility. To evaluate the larvicidal activity, H.contortus L3 were incubated with the extracts with varying concentration of 5 mg/mL, 10 mg/mL, 15 mg/mL and 20 mg/mL at 27°C for 48, 72 and 96 hrs. The results were subjected to the Kruskal-Wallis test (P less than 0.05). The extracts showed dose-dependent larvicidal effects. These results suggest that J.curcas can be used to control gastrointestinal nematodes of small ruminants.

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Development of a loop-mediated isothermal amplification (LAMP) assay for the identification of the invasive wood borer Aromia bungii (Coleoptera: Cerambycidae) from frass

3 Biotech ◽

10.1007/s13205-020-02602-w ◽

2021 ◽

Vol 11 (2) ◽

Author(s):

Domenico Rizzo ◽

Nicola Luchi ◽

Daniele Da Lio ◽

Linda Bartolini ◽

Francesco Nugnes ◽

...

Keyword(s):

Lamp Assay ◽

Isothermal Amplification ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Loop Mediated Isothermal Amplification ◽

Larval Stages ◽

Longhorn Beetle ◽

Rapid Monitoring ◽

Major Pest ◽

Wood Borer

AbstractThe red-necked longhorn beetle Aromia bungii (Faldermann, 1835) (Coleoptera: Cerambycidae) is native to east Asia, where it is a major pest of cultivated and ornamental species of the genus Prunus. Morphological or molecular discrimination of adults or larval specimens is required to identify this invasive wood borer. However, recovering larval stages of the pest from trunks and branches causes extensive damage to plants and is timewasting. An alternative approach consists in applying non-invasive molecular diagnostic tools to biological traces (i.e., fecal pellets, frass). In this way, infestations in host plants can be detected without destructive methods. This paper presents a protocol based on both real-time and visual loop-mediated isothermal amplification (LAMP), using DNA of A. bungii extracted from fecal particles in larval frass. Laboratory validations demonstrated the robustness of the protocols adopted and their reliability was confirmed performing an inter-lab blind panel. The LAMP assay and the qPCR SYBR Green method using the F3/B3 LAMP external primers were equally sensitive, and both were more sensitive than the conventional PCR (sensitivity > 103 to the same starting matrix). The visual LAMP protocol, due to the relatively easy performance of the method, could be a useful tool to apply in rapid monitoring of A. bungii and in the management of its outbreaks.

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The new Internal Transcribed Spacer 2 diagnostic tool clarifies the taxonomic position and geographic distribution of the North American malaria vector Anopheles punctipennis

Malaria Journal ◽

10.1186/s12936-021-03676-4 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

James M. Hodge ◽

Andrey A. Yurchenko ◽

Dmitriy A. Karagodin ◽

Reem A. Masri ◽

Ryan C. Smith ◽

...

Keyword(s):

Malaria Vector ◽

Internal Transcribed Spacer ◽

Single Species ◽

Its2 Sequence ◽

Pathogen Transmission ◽

Molecular Diagnostic ◽

Diagnostic Tools ◽

Sequence Length ◽

Phylogenetic Position ◽

Internal Transcribed Spacer 2

Abstract Background The malaria mosquito Anopheles punctipennis, a widely distributed species in North America, is capable of transmitting human malaria and is actively involved in the transmission of the ungulate malaria parasite Plasmodium odocoilei. However, molecular diagnostic tools based on Internal Transcribed Spacer 2 (ITS2) of ribosomal DNA are lacking for this species. Anopheles punctipennis is a former member of the Anopheles maculipennis complex but its systematic position remains unclear. Methods In this study, ITS2 sequences were obtained from 276 An. punctipennis specimens collected in the eastern and midwestern United States and a simple and robust Restriction Fragment Length Polymorphism approach for species identification was developed. The maximum-likelihood phylogenetic tree was constructed based on ITS2 sequences available through this study and from GenBank for 20 species of Anopheles. Results The analysis demonstrated a consistent ITS2 sequence length and showed no indications of intragenomic variation among the samples based on ITS2, suggesting that An. punctipennis represents a single species in the studied geographic locations. In this study, An. punctipennis was found in urban, rural, and forest settings, suggesting its potential broad role in pathogen transmission. Phylogeny based on ITS2 sequence comparison demonstrated the close relationship of this species with other members of the Maculipennis group. Conclusions This study developed molecular tools based on ITS2 sequences for the malaria vector An. punctipennis and clarified the phylogenetic position of the species within the Maculipennis group.

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Prevalence of Ovine Haemonchosis in Wukro, Ethiopia

Journal of Parasitology Research ◽

10.1155/2015/635703 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Lidya Gebresilassie ◽

Berihun Afera Tadele

Keyword(s):

Body Condition ◽

Haemonchus Contortus ◽

Significant Variation ◽

Cross Sectional Study ◽

Cross Sectional ◽

Highly Pathogenic ◽

Good Body Condition ◽

Associated Risk Factors ◽

Female Sheep ◽

Important Disease

Background.Haemonchosiscaused byHaemonchus contortusis a predominant, highly pathogenic, and economically important disease of sheep and goats.Objective. Assessing the prevalence ofHaemonchusparasite and its associated risk factors in sheep slaughtered at different restaurants of Wukro.Methods. Cross-sectional study using random sampling from November 2013 to April 2014 in a total of 384 sheep was conducted and SPSS version 20 software using descriptive statistics was used for data analysis andP<0.05was considered significant.Result. The overall prevalence ofHaemonchus contortuswas 40.9% (n=157). The prevalence in medium body condition 27.3% (n=105) varies significantly from that of good body condition 13.5% (n=52) (P<0.05). Moreover, there was significant variation (P<0.05) in the prevalence in young and adult sheep with rates of 21.9% (n=84) and 19% (n=73), respectively. At the same time, there is significant variation (P<0.05) in male and female sheep with prevalence of 29.7% (n=114) and 11.2% (n=43), respectively. The prevalence of 25.3% (n=97) in sheep that originated from Negash compared to Wukro and Agulae showed no significant variation (P>0.05).Conclusion. The current finding revealed that significant numbers of sheep were affected by the parasites. Hence strategic deworming with good husbandry practice should be implemented.

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