scholarly journals High frequency of benzimidazole resistance alleles in Haemonchus contortus, Teladorsagia circumcincta and Trichostrongylus colubriformis from Austrian sheep flocks in an alpine transhumance management system

2019 ◽  
Author(s):  
Barbara Hinney ◽  
Julia Schoiswohl ◽  
Lynsey Melville ◽  
Vahel J. Ameen ◽  
Walpurga Wille-Piazzai ◽  
...  
Keyword(s):  
Management System ◽  
Anthelmintic Resistance ◽  
Treatment Strategies ◽  
Small Ruminants ◽  
Nucleotide Polymorphisms ◽  
Sheep Population ◽  
Teladorsagia Circumcincta ◽  
Benzimidazole Resistance ◽  
Drug Classes ◽  
New Treatment

Abstract Infections of small ruminants with trichostrongyloid nematodes often result in reduced productivity and may be detrimental to the host. Anthelmintic resistance (AR) against most anthelmintic drug classes is now widespread amongst the trichostrongyloids. Baseline establishment, followed by regular monitoring of the level of AR, is necessary for farmers and veterinarians to make informed decisions about parasite management. The detection of single nucleotide polymorphisms (SNPs) is a sensitive method to detect AR against benzimidazoles (BZs), one of the most widely used anthelmintic classes. Alpine transhumance constitutes a special type of pasturing of sheep from many different farms, the aim of this study was to investigate the prevalence of benzimidazole resistance alleles in this particular management system. Sixteen sheep flocks in Styria and Salzburg in Austria were examined by pyrosequencing for SNPs at codons 167, 198 and 200 of the isotype-1 β-tubulin gene. The frequency of the resistance-associated mutation F200Y was 87–100% for H. contortus, 77–100% for T. colubriformis and <5–66% for T. circumcincta. Additionally, the F167Y polymorphism was detected in T. colubriformis from two farms at a frequency of 19% and 23% respectively. The high resistance allele frequency in H. contortus and T. colubriformis in the examined sheep population urgently calls for the development of new treatment strategies to sustainably control trichostrongyloid infections for this kind of pasturing, since the frequent mixing of flocks during the alpine summer grazing must be considered an important risk factor for the spread of resistant nematodes to a large number of farms.

scholarly journals High frequency of benzimidazole resistance alleles in trichostrongyloids from Austrian sheep flocks in an alpine transhumance management system 

2020 ◽  
Author(s):  
Barbara Hinney ◽  
Julia Schoiswohl ◽  
Lynsey Melville ◽  
Vahel J. Ameen ◽  
Walpurga Wille-Piazzai ◽  
...  
Keyword(s):  
Management System ◽  
Anthelmintic Resistance ◽  
Treatment Strategies ◽  
Small Ruminants ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Sheep Population ◽  
Benzimidazole Resistance ◽  
Drug Classes ◽  
New Treatment

Abstract Background: Infections of small ruminants with trichostrongyloid nematodes often result in reduced productivity and may be detrimental to the host. Anthelmintic resistance (AR) against most anthelmintic drug classes is now widespread amongst the trichostrongyloids. Baseline establishment, followed by regular monitoring of the level of AR, is necessary for farmers and veterinarians to make informed decisions about parasite management. The detection of single nucleotide polymorphisms (SNPs) is a sensitive method to detect AR against benzimidazoles (BZs), one of the most widely used anthelmintic classes. Alpine transhumance constitutes a special type of pasturing of sheep from many different farms, the aim of this study was to investigate the prevalence of benzimidazole resistance alleles in this particular management system. Results: Sixteen sheep flocks in Styria and Salzburg in Austria were examined by pyrosequencing for SNPs at codons 167, 198 and 200 of the isotype-1 β-tubulin gene. The frequency of the resistance-associated exchange F200Y was 87–100% for H. contortus, 77–100% for T. colubriformis and <5–66% for T. circumcincta. Additionally, the F167Y polymorphism was detected in T. colubriformis from two farms at a frequency of 19% and 23% respectively. Conclusions: The high resistance allele frequency in H. contortus and T. colubriformis in the examined sheep population urgently calls for the development of new treatment strategies to sustainably control trichostrongyloid infections for this kind of pasturing, since the frequent mixing of flocks during the alpine summer grazing must be considered an important risk factor for the spread of resistant nematodes to a large number of farms.

Multi-species Grazing for Control of Gastrointestinal Nematodes – a Review

2021 ◽  
Vol 99 (Supplement_2) ◽  
pp. 36-37
Author(s):  
Joan M Burke ◽  
James E Miller
Keyword(s):  
Anthelmintic Resistance ◽  
Small Ruminants ◽  
Gastrointestinal Nematode ◽  
Gastrointestinal Nematodes ◽  
Copper Tolerance ◽  
Resistant Species ◽  
Complex Interactions ◽  
Teladorsagia Circumcincta ◽  
Management Scheme ◽  
Time Required

Abstract Multi-species grazing, alternate grazing of cattle with sheep or goats, offers benefits to gastrointestinal nematode (GIN) control as GIN species differ between hosts. In the Southeastern United States, common GIN species of cattle include Cooperia spp., Ostertagia ostertagi, Haemonchus spp., whereas species of sheep and goats are Haemonchus contortus, Teladorsagia circumcincta, Trichostrongylus spp., Cooperia curticei, and Oesophagostomum spp. Anthelmintic resistance is widely prevalent in small ruminants, and is an increasing problem in cattle, but remains less prevalent. Thus, it is recommended to farmers to use a multi-faceted approach of GIN control, including multi-species grazing. Because management differs between cattle and small ruminants in regard to copper tolerance in minerals, predator control and fencing, alternate grazing of species has most commonly been used. Other considerations include age or susceptibility to GIN, as young calves may be vulnerable to GIN, but mature cows often have negligible GIN infection. Similarly, weanling lambs and kids are susceptible, and depending on breed, adults range from highly resistant to susceptible. Research indicates that GIN burden of more resistant animals is less influenced by multi-species grazing, and highly susceptible animals will likely need additional measures of control. The more resistant species used in the multi-species grazing may lend more control to the more susceptible. Some research showed reductions in O. ostertagi, but not C. oncophora in cattle during extended grazing of cattle and sheep, and reductions of H. contortus and T. colubriformis in sheep. However, other research reported similar worm burdens. Weight gains were improved in lambs grazed alternately with cattle in some studies, and most studies showed little benefit to cattle. Little has been published on alternate grazing with cattle and goats. The complex interactions, larger plot sizes needed, and time required to complete experiments limits published studies of this important management scheme.

scholarly journals Molecular Study of Benzimidazole Resistance in Teladorsagia circumcincta Isolated from Sheep in North of Iran

2019 ◽  
Author(s):  
Rahim NEMATI ◽  
Aliasghar BAHARI ◽  
Pezhman MAHMOODI ◽  
Alireza SAZMAND
Keyword(s):  
Anthelmintic Resistance ◽  
Molecular Study ◽  
Nucleotide Polymorphisms ◽  
Northern Iran ◽  
The North ◽  
Specific Pcr ◽  
Teladorsagia Circumcincta ◽  
Pcr Rflp ◽  
North Of Iran ◽  
Allele Specific

Background: Resistance to benzimidazole (BZ) compounds is common in Teladorsagia circumcincta populations in sheep and goats worldwide. Given the importance of anthelmintic resistance and shortage of information on single nucleotide polymorphisms (SNPs) in this prevalent nematode in Iran, this study was conducted. Methods: From June to September 2016, abomasa of 139 sheep of different sexes and ages in Amol City slaughterhouse, northern Iran were examined for isolation of nematodes. Totally 45 male T. circumcincta confirmed by both microscopical and nested-PCR-RFLP methods were included in this study. Susceptibility or resistance of each single T. circumcincta worm to benzimidazoles was assessed using allele-specific PCR. Results: Frequency of genotypes in the present study were 33.33% heterozygote BZ and 66.67% BZ homozygote sensitive. No homozygote resistant worm was found. Conclusion: Resistance against BZs in T. circumcincta of sheep has occurred at a low prevalence in the north of Iran. However, mutated genes might get dominant under drug selection in future. Hence, periodic investigations for early detection of mutated alleles in nematode populations using accurate and sensitive molecular methods such as PCR-RFLP is recommended.

scholarly journals Discovery of unique loci that underlie nematode responses to benzimidazoles

2017 ◽  
Author(s):  
Mostafa Zamanian ◽  
Daniel E. Cook ◽  
Stefan Zdraljevic ◽  
Shannon C. Brady ◽  
Daehan Lee ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Resistance Genes ◽  
Anthelmintic Resistance ◽  
Benzimidazole Derivatives ◽  
Parasitic Nematodes ◽  
C Elegans ◽  
Benzimidazole Resistance ◽  
Drug Classes ◽  
Parasite Populations ◽  
Parasite Drug Resistance

Parasitic nematodes impose a debilitating health and economic burden across much of the world. Nematode resistance to anthelmintic drugs threatens parasite control efforts in both human and veterinary medicine. Despite this threat, the genetic landscape of potential resistance mechanisms to these critical drugs remains largely unexplored. Here, we exploit natural variation in the model nematodes Caenorhabditis elegans and Caenorhabditis briggsae to discover quantitative trait loci (QTL) that control sensitivity to benzimidazoles widely used in human and animal medicine. High-throughput phenotyping of albendazole, fenbendazole, mebendazole, and thiabendazole responses in panels of recombinant lines led to the discovery of over 15 QTL in C. elegans and four QTL in C. briggsae associated with divergent responses to these anthelmintics. Many of these QTL are conserved across benzimidazole derivatives, but others show drug and dose specificity. We used near-isogenic lines to recapitulate and narrow the C. elegans albendazole QTL of largest effect and identified candidate variants correlated with the resistance phenotype. These QTL do not overlap with known benzimidazole resistance genes from parasitic nematodes and present specific new leads for the discovery of novel mechanisms of nematode benzimidazole resistance. Analyses of orthologous genes reveal significant conservation of candidate benzimidazole resistance genes in medically important parasitic nematodes. These data provide a basis for extending these approaches to other anthelmintic drug classes and a pathway towards validating new markers for anthelmintic resistance that can be deployed to improve parasite disease control.Author SummaryThe treatment of roundworm (nematode) infections in both humans and animals relies on a small number of anti-parasitic drugs. Resistance to these drugs has appeared in veterinary parasite populations and is a growing concern in human medicine. A better understanding of the genetic basis for parasite drug resistance can be used to help maintain the effectiveness of anti-parasitic drugs and to slow or to prevent the spread of drug resistance in parasite populations. This goal is hampered by the experimental intractability of nematode parasites. Here, we use non-parasitic model nematodes to systematically explore responses to the critical benzimidazole class of anti-parasitic compounds. Using a quantitative genetics approach, we discovered unique genomic intervals that control drug effects, and we identified differences in the genetic architectures of drug responses across compounds and doses. We were able to narrow a major-effect genomic region associated with albendazole resistance and to establish that candidate genes discovered in our genetic mappings are largely conserved in important human and animal parasites. This work provides new leads for understanding parasite drug resistance and contributes a powerful template that can be extended to other anti-parasitic drug classes.

scholarly journals Chemical Analysis and Anthelmintic Activity Against Teladorsagia Circumcincta of Nordic Bark Extracts In vitro

2021 ◽  
Vol 8 ◽  
Author(s):  
Spiridoula Athanasiadou ◽  
Marit Almvik ◽  
Jarkko Hellström ◽  
Eva Madland ◽  
Nebojsa Simic ◽  
...  
Keyword(s):  
Anthelmintic Resistance ◽  
Condensed Tannin ◽  
Small Ruminants ◽  
Anthelmintic Activity ◽  
Tree Age ◽  
Parasitic Infections ◽  
Teladorsagia Circumcincta ◽  
The Impact ◽  
Anthelmintic Drugs

Helminth parasitic infections are common in small ruminants in Norway; infection is usually treated with anthelmintic drugs, but anthelmintic resistance is an increasing problem. It is necessary to identify strategies to reduce the use of anthelmintic drugs and mitigate the impact of anthelmintic resistance. Condensed tannin (CT)-rich forages have been shown to reduce the helminth burden in small ruminants, but these forages have limited cultivation potential in Scandinavia. A good source for CT in cold climatic regions may be the bark of several commercially utilized tree species. In the present study, we determined the content and characterized the type of CT in bark extracts of pine (Pinus sylvestris L.), spruce (Picea abies L.), and birch (Betula pubescens). Extracts of selected bark samples were tested for their anthelmintic efficacy against the ovine infectious nematode Teladorsagia circumcincta. Total CT content was higher in the bark from younger (10–40 years old) pine and spruce trees; it decreased with tree age in pine, whereas it remained relatively stable in the bark of spruce and birch. Pine trees consisted of 100% procyanidins, whereas prodelphinins were present in most spruce (4–17%) and all birch samples (5–34%). Our studies clearly showed that there is variation in the anthelmintic activity of water and acetone extracts of bark samples collected from various sites around Norway, as this was measured with two independent in vitro assays, the egg hatch and larvae motility assays. The anthelmintic activity of some extracts was consistent between the two assays; for example, extracts from the three samples with the highest CT content showed very high activity in both assays, whereas the extract from the sample with the lowest CT content showed the lowest activity in both assays. For other extracts, activity was not consistent across the assays, which could be attributed to the susceptibility of the different stages of the parasitic life cycle. We demonstrated that bark extracts from commercially used trees in Scandinavia have the potential to be used as alternatives to anthelmintics. Further work should focus on refining the associations between bark extracts and anthelmintic activity to identify the best strategies to reduce the input of anthelmintic drugs in livestock production systems.

Effect of Jatropha curcas Latex on L3 Haemonchus contortus Larval Motility

2017 ◽  
Vol 9 (3) ◽  
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.

Humoral Immunity in Heart Failure

2019 ◽  
Vol 19 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Amrita Sarkar ◽  
Khadija Rafiq
Keyword(s):  
Heart Failure ◽  
Humoral Immunity ◽  
Treatment Strategies ◽  
Pathophysiological Mechanism ◽  
Peripheral Vascular ◽  
Cardiac Inflammation ◽  
Humoral Immune ◽  
Humoral Immune System ◽  
New Treatment ◽  
Immunity Function

Cardiovascular Disease (CVD) is a class of diseases that involve disorders of heart and blood vessels, including hypertension, coronary heart disease, cerebrovascular disease, peripheral vascular disease, which finally lead to Heart Failure (HF). There are several treatments available all over the world, but still, CVD and heart failure became the number one problem causing death every year worldwide. Both experimental and clinical studies have shown a role for inflammation in the pathogenesis of heart failure. This seems related to an imbalance between pro-inflammatory and anti-inflammatory cytokines. Cardiac inflammation is a major pathophysiological mechanism operating in the failing heart, regardless of HF aetiology. Disturbances of the cellular and humoral immune system are frequently observed in heart failure. This review describes how B-cells play a specific role in the heart failure states. There is an urgent need to identify novel therapeutic targets and develop advanced therapeutic strategies to combat the syndrome of HF. Understanding and describing the elements of the humoral immunity function are essential and may suggest potential new treatment strategies.

scholarly journals Emerging Natural-Product-Based Treatments for the Management of Osteoarthritis

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 265
Author(s):  
Maria-Luisa Pérez-Lozano ◽  
Annabelle Cesaro ◽  
Marija Mazor ◽  
Eric Esteve ◽  
Sabine Berteina-Raboin ◽  
...  
Keyword(s):  
Bone Resorption ◽  
Natural Product ◽  
Treatment Strategies ◽  
Cartilage Degradation ◽  
Therapeutic Strategies ◽  
Clinical Models ◽  
Osteoarthritic Joint ◽  
Dietary Components ◽  
New Treatment ◽  
Review Current

Osteoarthritis (OA) is a complex degenerative disease in which joint homeostasis is disrupted, leading to synovial inflammation, cartilage degradation, subchondral bone remodeling, and resulting in pain and joint disability. Yet, the development of new treatment strategies to restore the equilibrium of the osteoarthritic joint remains a challenge. Numerous studies have revealed that dietary components and/or natural products have anti-inflammatory, antioxidant, anti-bone-resorption, and anabolic potential and have received much attention toward the development of new therapeutic strategies for OA treatment. In the present review, we provide an overview of current and emerging natural-product-based research treatments for OA management by drawing attention to experimental, pre-clinical, and clinical models. Herein, we review current and emerging natural-product-based research treatments for OA management.

scholarly journals The Optimal First-Line Therapy ofHelicobacter pyloriInfection in Year 2012

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Chao-Hung Kuo ◽  
Fu-Chen Kuo ◽  
Huang-Ming Hu ◽  
Chung-Jung Liu ◽  
Sophie S. W. Wang ◽  
...  
Keyword(s):  
Rescue Therapy ◽  
Treatment Strategies ◽  
Sequential Therapy ◽  
Antibiotics Resistance ◽  
First Line ◽  
First Line Therapy ◽  
Metronidazole Resistance ◽  
Rescue Treatment ◽  
New Treatment ◽  
H Pylori

This paper reviews the literature about first-line therapies forH. pyloriinfection in recent years. First-line therapies are facing a challenge because of increasing treatment failure due to elevated antibiotics resistance. Several new treatment strategies that recently emerged to overcome antibiotic resistance have been surveyed. Alternative first-line therapies include bismuth-containing quadruple therapy, sequential therapy, concomitant therapy, and hybrid therapy. Levofloxacin-based therapy shows impressive efficacy but might be employed as rescue treatment due to rapidly raising resistance. Rifabutin-based therapy is also regarded as a rescue therapy. Several factors including antibiotics resistance, patient compliance, and CYP 2C19 genotypes could influence the outcome. Clinicians should use antibiotics according to local reports. It is recommended that triple therapy should not be used in areas with high clarithromycin resistance or dual clarithromycin and metronidazole resistance.

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