1
|
Elghryani N, Lawlor A, McOwan T, de Waal T. Unravelling the Effectiveness of Anthelmintic Treatments on Equine Strongyles on Irish Farms. Animals (Basel) 2024; 14:1958. [PMID: 38998069 PMCID: PMC11240484 DOI: 10.3390/ani14131958] [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: 05/07/2024] [Revised: 06/19/2024] [Accepted: 06/26/2024] [Indexed: 07/14/2024] Open
Abstract
Over the preceding decades, the widespread dependence on anthelmintic drugs for managing nematodes in grazing equids has given rise to resistance against commonly used anthelmintics in various countries. This study explores the prevalence of anthelmintic resistance across 44 horse farms in Ireland. Anthelmintic efficacy was evaluated through fecal egg count reduction (FECR) tests employing the mini-FLOTAC technique. Resistance to benzimidazoles was identified in 12 out of 14 farms (FECR range: 0.00% to 86.2%). Ivermectin resistance was observed on two farms, one with an FECR of 80.70% and another with an FECR of 96.10% (lower 95% high probability density interval (HPD) <90%, 11.70%). On the remaining six farms, the reduction with ivermectin still exceeded 95%. The reduced efficacy of moxidectin was noted on two farms (FECR = 86.90% and 93.50%) and on a third farm with an FECR of 99.50 and a lower HPD interval < 90% at 24.00%. In summary, these findings emphasize the urgent need for alternative strategies in equine strongyle control that reduce reliance on anthelmintics and prioritize effective management practices on Irish equine farms to hinder the impending development of drug-resistant parasite populations.
Collapse
Affiliation(s)
- Nagwa Elghryani
- School of Veterinary Medicine, University College Dublin, D04 W6F6 Dublin, Ireland
- Telenostic Limited, R95 WN20 Kilkenny, Ireland
- Department of Biology, Faculty of Arts and Sciences-Gamines, University of Benghazi, Benghazi 1308, Libya
| | - Amanda Lawlor
- School of Veterinary Medicine, University College Dublin, D04 W6F6 Dublin, Ireland
| | | | - Theo de Waal
- School of Veterinary Medicine, University College Dublin, D04 W6F6 Dublin, Ireland
| |
Collapse
|
2
|
Rendle D, Hughes K, Bowen M, Bull K, Cameron I, Furtado T, Peachey L, Sharpe L, Hodgkinson J. BEVA primary care clinical guidelines: Equine parasite control. Equine Vet J 2024; 56:392-423. [PMID: 38169127 DOI: 10.1111/evj.14036] [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: 07/13/2023] [Accepted: 11/16/2023] [Indexed: 01/05/2024]
Abstract
BACKGROUND There is a lack of consensus on how best to balance our need to minimise the risk of parasite-associated disease in the individual horse, with the need to limit the use of anthelmintics in the population to preserve their efficacy through delaying further development of resistance. OBJECTIVES To develop evidence-based guidelines utilising a modified GRADE framework. METHODS A panel of veterinary scientists with relevant expertise and experience was convened. Relevant research questions were identified and developed with associated search terms being defined. Evidence in the veterinary literature was evaluated using the GRADE evidence-to-decision framework. Literature searches were performed utilising CAB abstracts and PubMed. Where there was insufficient evidence to answer the research question the panel developed practical guidance based on their collective knowledge and experience. RESULTS Search results are presented, and recommendation or practical guidance were made in response to 37 clinically relevant questions relating to the use of anthelmintics in horses. MAIN LIMITATIONS There was insufficient evidence to answer many of the questions with any degree of certainty and practical guidance frequently had to be based upon extrapolation of relevant information and the panel members' collective experience and opinions. CONCLUSIONS Equine parasite control practices and current recommendations have a weak evidence base. These guidelines highlight changes in equine parasite control that should be considered to reduce the threat of parasite-associated disease and delay the development of further anthelmintic resistance.
Collapse
Affiliation(s)
| | - Kristopher Hughes
- School of Agricultural, Environmental and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
| | - Mark Bowen
- Medicine Vet Referrals, Nottinghamshire, UK
| | - Katie Bull
- Bristol Veterinary School, University of Bristol, Bristol, UK
| | | | - Tamzin Furtado
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK
| | - Laura Peachey
- Bristol Veterinary School, University of Bristol, Bristol, UK
| | | | - Jane Hodgkinson
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Neston, UK
| |
Collapse
|
3
|
Cai E, Wu R, Wu Y, Gao Y, Zhu Y, Li J. A systematic review and meta-analysis on the current status of anthelmintic resistance in equine nematodes: A global perspective. Mol Biochem Parasitol 2024; 257:111600. [PMID: 38030084 DOI: 10.1016/j.molbiopara.2023.111600] [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: 03/31/2023] [Revised: 11/22/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023]
Abstract
BACKGROUND The intensive application of anthelmintics in equine has led to considerable resistance in cyathostomins and Parascaris equorum. It has been well documented that benzimidazole (BZ) and pyrantel resistance is widespread in cyathostomins and Parascaris equorum. Since no new classes of anthelmintic have been introduced in the last 40 years, it is critical to be aware of the current risk factors of anthelmintic application to avoid further resistance. OBJECTIVE To review the factors affecting the level of anthelmintics resistance in equine around the world, type of anthelmintics, mode of application, dosage, nematode species, and location of anthelmintics application were evaluated and summarized. DESIGN/PROCEDURE A systematic review and meta-analyses following the PRISMA Framework were conducted to identify, evaluate, and synthesize primary literature reporting the efficacy of anthelmintic drugs in equines. Information on the bibliographic data, anthelmintic drugs, animals, continents, parasite genera, type of anthelmintics, and dosage was collected. Nonparametric tests (Kruskal-Wallis and Mann-Whitney) were used in SPSS (v.27) to investigate the association between variables. Factors that have a significant impact on efficacy have been subjected to binary logistic regression. Six meta-analyses were conducted in Microsoft Excel (2021) to qualify current resistance issues of the three major anthelmintics classes. RESULTS The final database was composed of 60 articles published between 1994 and 2022 with a total of 11835 animals. Anthelmintic class as well as anthelmintic active principle selection did have a significant effect on resistance (P < 0.01), whilst no correlation of the type of anthelmintics, mode of application, and dosage with efficacy were found. Anthelmintics resistance in ascarid was significantly more severe than in strongyle (P < 0.01). Macrocyclic lactone (ML) class and the benzimidazole and probenzimidazole (BP) class have the lowest efficacy against ascarid and strongyle, respectively (67.83% and 69.85%). The effect of location (by continent) also had a significant influence on the resistance of the ML class (P < 0.01). The resistance of the BP class which is the most prevalently applied was demonstrated in all six continents. Binary logistic regression revealed that parasite genera and drug class independently influenced the presence of drug resistance. The forest plots included in this study did not show a significant difference over time. CONCLUSION Current evidence indicated that anthelmintics resistance of ML and BP class were common in ascarid and strongyle. A combination of anthelmintics may reduce anthelmintics resistance, but multi-drug resistance may be a concern. Customerised anthelmintics strategy could help reduce resistance.
Collapse
Affiliation(s)
- Enjia Cai
- Equine Clinical Diagnostic Center, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Rongzheng Wu
- Equine Clinical Diagnostic Center, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Yuhong Wu
- College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, United States
| | - Yu Gao
- University of Veterinary Medicine Hannover Foundation, Hannover D-30559, Germany
| | - Yiping Zhu
- Equine Clinical Diagnostic Center, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
| | - Jing Li
- Equine Clinical Diagnostic Center, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China.
| |
Collapse
|
4
|
Hedberg Alm Y, Halvarsson P, Martin F, Osterman-Lind E, Törngren V, Tydén E. Demonstration of reduced efficacy against cyathostomins without change in species composition after pyrantel embonate treatment in Swedish equine establishments. Int J Parasitol Drugs Drug Resist 2023; 23:78-86. [PMID: 37979235 PMCID: PMC10690405 DOI: 10.1016/j.ijpddr.2023.11.003] [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: 08/26/2023] [Revised: 11/07/2023] [Accepted: 11/08/2023] [Indexed: 11/20/2023]
Abstract
Consisting of approximately 50 different species, the cyathostomin parasites are ubiquitous in grazing horses. Co-infection with several species is common, and large burdens can cause the fatal disease of larval cyathostominosis. Due to intense anthelmintic drug use, cyathostomin resistance has developed to all available anthelmintic drug groups. Resistance to the anthelmintic drug pyrantel (PYR) has been documented in over 90% of studies published over the past two decades. In Sweden, a study performed in the early 2000s only confirmed resistance in 4.5% of farms. Further, prescription-only administration of equine anthelmintic drugs was enforced in Sweden in 2007. However, it is unknown if this conservative drug use has maintained PYR efficacy in cyathostomins. The aim of the present study was to investigate the effect of PYR on cyathostomin infection in Sweden using fecal egg count reduction tests (FECRTs). Further, the effect of PYR treatment on cyathostomin species composition was studied using metabarcoding. Sixteen farms with at least six horses excreting a minimum of 100 eggs per gram feces were included. Using the current World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines, PYR resistance was demonstrated in nine of farms, with seven farms showing full susceptibility. Farms with low biosecurity measures had significantly lower efficacy of PYR treatment. The most common cyathostomin species were Cylicocyclus nassatus, Cyathostomum catinatum, Cylicostephanus longibursatus, Cys. calicatus, Cys. goldi, Cys. minutus, Coronocyclus coronatus and Cya. pateratum, accounting for 97% of all sequence reads prior to treatment. Of these, Cyc. nassatus and Cya. catinatum had the highest occurrence, accounting for 68% of all sequence reads prior to PYR treatment. Treatment did not significantly affect the species composition. The results highlight the importance of drug efficacy testing when using PYR to treat cyathostomin infection, even when selective anthelmintic treatment and thus low treatment intensity, is used on the farm.
Collapse
Affiliation(s)
- Ylva Hedberg Alm
- Department of Biomedical Science and Veterinary Public Health, Parasitology Unit, Swedish University of Agricultural Sciences, SE-750 07, Uppsala, Sweden.
| | - Peter Halvarsson
- Department of Biomedical Science and Veterinary Public Health, Parasitology Unit, Swedish University of Agricultural Sciences, SE-750 07, Uppsala, Sweden
| | - Frida Martin
- Department of Biomedical Science and Veterinary Public Health, Parasitology Unit, Swedish University of Agricultural Sciences, SE-750 07, Uppsala, Sweden
| | - Eva Osterman-Lind
- Department of Microbiology, Section for Parasitology, National Veterinary Institute (SVA), SE-751 89, Uppsala, Sweden
| | - Vendela Törngren
- Department of Biomedical Science and Veterinary Public Health, Parasitology Unit, Swedish University of Agricultural Sciences, SE-750 07, Uppsala, Sweden
| | - Eva Tydén
- Department of Biomedical Science and Veterinary Public Health, Parasitology Unit, Swedish University of Agricultural Sciences, SE-750 07, Uppsala, Sweden
| |
Collapse
|
5
|
Kaplan RM, Denwood MJ, Nielsen MK, Thamsborg SM, Torgerson PR, Gilleard JS, Dobson RJ, Vercruysse J, Levecke B. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guideline for diagnosing anthelmintic resistance using the faecal egg count reduction test in ruminants, horses and swine. Vet Parasitol 2023; 318:109936. [PMID: 37121092 DOI: 10.1016/j.vetpar.2023.109936] [Citation(s) in RCA: 40] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Accepted: 04/18/2023] [Indexed: 05/02/2023]
Abstract
The faecal egg count reduction test (FECRT) remains the method of choice for establishing the efficacy of anthelmintic compounds in the field, including the diagnosis of anthelmintic resistance. We present a guideline for improving the standardization and performance of the FECRT that has four sections. In the first section, we address the major issues relevant to experimental design, choice of faecal egg count (FEC) method, statistical analysis, and interpretation of the FECRT results. In the second section, we make a series of general recommendations that are applicable across all animals addressed in this guideline. In the third section, we provide separate guidance details for cattle, small ruminants (sheep and goats), horses and pigs to address the issues that are specific to the different animal types. Finally, we provide overviews of the specific details required to conduct an FECRT for each of the different host species. To address the issues of statistical power vs. practicality, we also provide two separate options for each animal species; (i) a version designed to detect small changes in efficacy that is intended for use in scientific studies, and (ii) a less resource-intensive version intended for routine use by veterinarians and livestock owners to detect larger changes in efficacy. Compared to the previous FECRT recommendations, four important differences are noted. First, it is now generally recommended to perform the FECRT based on pre- and post-treatment FEC of the same animals (paired study design), rather than on post-treatment FEC of both treated and untreated (control) animals (unpaired study design). Second, instead of requiring a minimum mean FEC (expressed in eggs per gram (EPG)) of the group to be tested, the new requirement is for a minimum total number of eggs to be counted under the microscope (cumulative number of eggs counted before the application of a conversion factor). Third, we provide flexibility in the required size of the treatment group by presenting three separate options that depend on the (expected) number of eggs counted. Finally, these guidelines address all major livestock species, and the thresholds for defining reduced efficacy are adapted and aligned to host species, anthelmintic drug and parasite species. In conclusion, these new guidelines provide improved methodology and standardization of the FECRT for all major livestock species.
Collapse
Affiliation(s)
- Ray M Kaplan
- Pathobiology Department, School of Veterinary Medicine, St. George's University, W.I., Grenada.
| | - Matthew J Denwood
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Martin K Nielsen
- Maxwell H. Gluck Equine Research Center, University of Kentucky, KY, USA
| | - Stig M Thamsborg
- Department of Veterinary and Animal Sciences, University of Copenhagen, Denmark
| | - Paul R Torgerson
- Section of Epidemiology, Vetsuisse Faculty, University of Zürich, Switzerland
| | - John S Gilleard
- Department of Comparative Biology and Experimental Medicine, Host-Parasite Interactions Program, Faculty of Veterinary Medicine, University of Calgary, Alberta, Canada
| | - Robert J Dobson
- School of Veterinary and Life Sciences, Murdoch University, Australia
| | - Jozef Vercruysse
- Department of Translational Physiology, Infectiology and Public Health, Ghent University, Merelbeke, Belgium
| | - Bruno Levecke
- Department of Translational Physiology, Infectiology and Public Health, Ghent University, Merelbeke, Belgium
| |
Collapse
|
6
|
Bull KE, Allen KJ, Hodgkinson JE, Peachey LE. The first report of macrocyclic lactone resistant cyathostomins in the UK. Int J Parasitol Drugs Drug Resist 2023; 21:125-130. [PMID: 36940551 PMCID: PMC10036890 DOI: 10.1016/j.ijpddr.2023.03.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 03/01/2023] [Accepted: 03/01/2023] [Indexed: 03/09/2023]
Abstract
In recent years, resistance to the benzimidazole (BZ) and tetrahydropyrimidine (PYR) anthelmintics in global cyathostomin populations, has led to reliance on the macrocyclic lactone drugs (ML-of which ivermectin and moxidectin are licensed in horses) to control these parasites. Recently, the first confirmed case of resistance to both ivermectin (IVM) and moxidectin (MOX) was reported in the USA in yearlings imported from Ireland. This suggests that ML resistance in cyathostomins has emerged, and raises the possibility that regular movement of horses may result in rapid spread of ML resistant cyathostomins. Resistance may go undetected due to a lack of surveillance for ML efficacy. Here, we report anthelmintic efficacies in cyathostomins infecting UK Thoroughbreds on four studs. Faecal egg count reduction tests (FECRT) were performed to define resistance (resistance = FECR <95% lower credible interval (LCI) < 90%). Stud A yearlings had FECRs of 36.4-78.6% (CI:15.7-86.3) after three IVM treatments, 72.6% (CI: 50.8-85.2) after MOX, and 80.8% (CI: 61.9-90.0) after PYR. Mares on stud A had a FECR of 97.8% (CI: 93.3-99.9) and 98% (95.1-99.4) after IVM and MOX treatment, respectively. Resistance to MLs was not found in yearlings or mares on studs B, C or D with FECR after MOX OR IVM treatment ranging from 99.8 to 99.9% (95.4-100); although yearlings on studs B, C and D all had an egg reappearance period (ERP) of six weeks for MOX and stud C had a four-week ERP for IVM. This study describes the first confirmed case of resistance to both licensed ML drugs on a UK Thoroughbred stud and highlights the urgent need for a) increased awareness of the threat of ML resistant parasites infecting horses, and b) extensive surveillance of ML efficacy against cyathostomin populations in the UK, to gauge the extent of the problem.
Collapse
Affiliation(s)
- K E Bull
- Bristol Veterinary School, University of Bristol, Bristol, BS40 5DU, UK.
| | - K J Allen
- Bristol Veterinary School, University of Bristol, Bristol, BS40 5DU, UK
| | - J E Hodgkinson
- Department of Infection Biology, Institute of Infection & Global Health, University of Liverpool, L3 5RF, UK
| | - L E Peachey
- Bristol Veterinary School, University of Bristol, Bristol, BS40 5DU, UK
| |
Collapse
|
7
|
Walshe N, Burrell A, Kenny U, Mulcahy G, Duggan V, Regan A. A qualitative study of perceived barriers and facilitators to sustainable parasite control on thoroughbred studs in Ireland. Vet Parasitol 2023; 317:109904. [PMID: 36907136 DOI: 10.1016/j.vetpar.2023.109904] [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: 09/02/2022] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 03/07/2023]
Abstract
In view of the rising threat of anthelmintic resistance in parasite populations and the planned change of classification of anthelmintics in Ireland for food animals to prescription-only medicines, there is a need for increased focus on parasite control strategies for horses. Effective parasite control programs (PCPs) are complex, necessitating the application of risk-assessment based on host immune status, infection pressure, type of parasite and seasonality to determine the requirement for anthelmintic administration and an understanding of parasite biology to employ effective, non- therapeutic, parasite control measures. The aim of this study was to explore horse breeders' attitudes and behaviours towards general parasite control practices and anthelmintic use on thoroughbred studs in Ireland using qualitative research methods, in order to help identify barriers to the implementation of sustainable equine PCPs supported by veterinary involvement. One-to-one, qualitative, semi-structured interviews were conducted with 16 breeders, using an interview topic guide that allowed for an open questioning style. The topic guide facilitated discussion around the following areas: (i) parasite control measures (general approach, (ii) veterinary involvement, (iii) use of anthelmintics, (iv) use of diagnostics, pasture management), (v) recording of anthelmintic use and (vi) anthelmintic resistance. Convenience, purposive (subjective selection) sampling was used to select a small group of participants that reflected the characteristics of current thoroughbred breeders in Ireland taking into account farm type, farm size, geographical location. The interviews were transcribed, and a method of inductive thematic analysis (a data driven identification and analysis of themes) was performed. Assessment of current behaviours by these participants found that PCPs were primarily based on the prophylactic use of anthelmintics without a strategic rationale. A key driver of behaviour regarding parasite prevention practices was localised routine, dictated by tradition, that gave breeders a sense of confidence and protection regarding parasite control. The perceptions of the benefits of parasitology diagnostics were varied and their application to control was poorly understood. Anthelmintic resistance was recognised as an industry threat but not an issue for individual farms. By using a qualitative approach, this study offers insights into the possible barriers to the adoption of sustainable PCPs on Irish thoroughbred farms and highlights the need for end-user involvement in the preparation of future guidelines.
Collapse
Affiliation(s)
- Nicola Walshe
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin, Ireland.
| | - Alison Burrell
- Animal Health Ireland, 2-5 The Archways, Carrick-on-Shannon, Co. Leitrim., Ireland
| | - Ursula Kenny
- One Health and One Welfare Scientific Support Team, National Disease Control Centre, Department of Agriculture, Food and the Marine, Kildare St., Dublin, Ireland
| | - Grace Mulcahy
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin, Ireland; Conway Institute, University College Dublin, Dublin, Ireland
| | - Vivienne Duggan
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - Aine Regan
- Department of Agri-food Business & Spatial Analysis, Teagasc, Ashtown Food Research Centre, Dublin 15, Ireland
| |
Collapse
|
8
|
Nielsen MK. Anthelmintic resistance in equine nematodes: Current status and emerging trends. Int J Parasitol Drugs Drug Resist 2022; 20:76-88. [PMID: 36342004 PMCID: PMC9630620 DOI: 10.1016/j.ijpddr.2022.10.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/19/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022]
Abstract
Anthelmintic resistance is reported in equine nematodes with increasing frequency in recent years, and no new anthelmintic classes have been introduced during the past 40 years. This manuscript reviews published literature describing anthelmintic resistance in cyathostomins, Parascaris spp., and Oxyuris equi with special emphasis on larvicidal efficacy against encysted cyathostomin larvae and strongylid egg reappearance periods (ERP). Resistance to benzimidazoles and pyrimidines is highly prevalent in cyathostomin populations around the world, and macrocyclic lactone resistance has been documented in cyathostomins in recent years as well. Two recent studies have documented resistance to the larvicidal regimen of fenbendazole, whereas the larvicidal efficacy of moxidectin is variable, but with no evidence of a reduction from historic levels. In the 1990s, ERP estimates were 8-10 and 12-16 weeks for ivermectin and moxidectin, respectively, while several studies published after year 2000 found ERPs to be 5 weeks for both compounds. This is a clear change in anthelmintic performance, but it remains unclear if this is due to development of anthelmintic resistance or selection for other biological traits leading to a quicker resumption of strongylid egg shedding following anthelmintic treatment. Macrocyclic lactone resistance is common in Parascaris spp. around the world, but recent reports suggests that resistance to the two other classes should be monitored as well. Finally, O. equi has been reported resistant to ivermectin and moxidectin in countries representing four continents. In conclusion, multi-drug resistance is becoming the norm in managed cyathostomin populations around the world, and a similar pattern may be emerging in Parascaris spp. More work is required to understand the mechanisms behind the shortened ERPs, and researchers and veterinarians around the world are encouraged to routinely monitor anthelmintic efficacy against equine nematodes.
Collapse
Affiliation(s)
- M K Nielsen
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, USA.
| |
Collapse
|
9
|
Apolinário ECF, Oliveira LLDS, Rocha RHF, Silva FVE, Santos IS, Alves CA, Dias Júnior JA, Mendes LDJ, Lima WDS. Anthelmintic efficacy in strongyles of horses in Northern Minas Gerais, Brazil. Vet Parasitol Reg Stud Reports 2022; 36:100810. [PMID: 36436897 DOI: 10.1016/j.vprsr.2022.100810] [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: 04/21/2022] [Revised: 10/18/2022] [Accepted: 11/14/2022] [Indexed: 11/25/2022]
Abstract
The intensive use of anthelmintics has resulted in resistant parasite populations in horses. The objective of this trial was to evaluate the anthelmintic efficacies of the anthelmintics fenbendazole, ivermectin and abamectin in 24 horse farms in Northern Minas Gerais. Egg counts per gram of faeces (EPG) were performed individually in 619 animals. Animals presenting EPG counts greater than or equal to 150 were used in the tests on faecal egg count reduction (FECR), totalling 436 equines. These animals received the anthelmintics, fenbendazole, ivermectin, and abamectin. Faeces were collected 14 days after the administration of anthelmintics to perform the EPG. Pre- and post-treatment EPG counts were used to calculate the FECR for each anthelmintic group, and faecal culture was used to identificy of the strongyles. The resistance status was evaluated based on the FECR and LCL95%. Fenbendazole was effective in 11 (45.8%) of the horse farms. Ivermectin was effective in 17 (77.3%) and abamectin in 17 (74%) of the farms; side-resistance was detected in 3 (12.5%) of the farms. Intestinal strongyle resistance to anthelmintics was observed in 14 (58.3%) of the farms. Cyathostomin larvae were found in 100% of the farms, Strongylus vulgaris in 13 (54.2%), and S. equinus in 3 (12.5%). Only cyathostomins larvae were detected post-treatment with ivermectin and abamectin.
Collapse
Affiliation(s)
- Estefânia Conceição Felipe Apolinário
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil
| | - Laura Lúcia Dos Santos Oliveira
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil.
| | - Raul Herberth Freitas Rocha
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil
| | - Fredson Vieira E Silva
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil.
| | - Izadora Souza Santos
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil
| | - Cleison Augusto Alves
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil
| | - José Alisson Dias Júnior
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil
| | - Laydiane de Jesus Mendes
- Departamento de Ciências Agrárias, Universidade Estadual de Montes Claros (UNIMONTES), Reinaldo Viana Av., São Vicente, 39.448-524 Janaúba, MG, Brazil
| | - Walter Dos Santos Lima
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Presidente Antônio Carlos Av., 6627, 31270-901 Belo Horizonte, MG, Brazil.
| |
Collapse
|
10
|
Dauparaitė E, Kupčinskas T, Varady M, Petkevičius S. Anthelmintic resistance of horse strongyle nematodes to fenbendazole in Lithuania. Acta Vet Scand 2022; 64:26. [PMID: 36109767 PMCID: PMC9479362 DOI: 10.1186/s13028-022-00645-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 09/07/2022] [Indexed: 11/30/2022] Open
Abstract
Background Control of strongyle infections presents a global challenge for horse practitioners due to the development of anthelmintic resistance (AR), however comprehensive information on AR in Lithuania is still lacking. The aim of this study was to assess the current situation of fenbendazole (FBZ) AR in horses at stable level in Lithuania. Results Faecal samples from 121 horses from six stables were examined using the Mini-FLOTAC method. Of these, 89 horses met the inclusion criteria that included strongyle faecal egg counts (FEC) exceeding 200 eggs per gram (EPG). Faecal egg count reduction tests (FECRTs) were performed in these. AR was evaluated at horse stable level based on faecal egg count reduction (FECR) and the lower limit of the 95% credible interval (LLCI) using the Bayesian hierarchical model. This study confirmed that strongylids (Cyathostominae (CYA)) resistant to FBZ are pervasive in Lithuania. FBZ was ineffective in three of the six stables (FECR 77.1–79.0%; 49.8–99.8 LLCI), was suspected to be ineffective in one stable (FECR 93.6%; 85.4–100 LLCI) and was effective (FECR 99.8–100%; 99.8–100 LLCI) in two stables. FEC showed a significant (P < 0.01) difference between the treatment and control groups. Only CYA larvae were detected in larval cultures derived from strongyle-positive faecal samples collected 14 days after treatment of a test group with FBZ. Conclusion This in vivo study showed that resistance to FBZ in the treatment of strongyle nematodes is prevalent in horse stables in Lithuania. These findings should guide the implementation of more sustainable management of strongyle infections in horses in Lithuania.
Collapse
|
11
|
Study on Gastrointestinal Nematodes of Equines in and around Bekoji, South Eastern Ethiopia. J Parasitol Res 2022; 2022:8210160. [PMID: 35677390 PMCID: PMC9170501 DOI: 10.1155/2022/8210160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/04/2022] [Accepted: 05/12/2022] [Indexed: 11/25/2022] Open
Abstract
Parasitic infections can cause a variety of respiratory, intestinal, and other problems in horses, as well as contribute to some performance issues. A cross-sectional study was undertaken in and around Bekoji, South Eastern Ethiopia, from November 2020 to June 2021 to identify species and evaluate the prevalence of gastrointestinal parasites in donkeys and horses, using direct fecal smear, floatation methods, and larval cultures. In this study, the overall prevalence of gastrointestinal nematode parasites was 94.5% (363 out of 384), with donkeys accounting for 95.8% and horses accounting for 90.5%. The coprological study indicated that an overall prevalence of gastrointestinal nematode parasites was 87%, 8.3%, 2.5%, 1.4%, and 0.8% for mixed parasite infection, nonmigratory strongylids, migratory strongylids, Parascaris equorum, and Oxyuris equi, respectively. Among mixed infections, nonmigratory strongylids+migratory strongylids (51.5%) occurred most frequently. The odds of male horses being infected by GIT nematodes were 1.59 times higher than male donkeys. Horses which have poor body condition were 2.94 times more infected than donkeys. The odds of old-aged donkeys were 3.11 times more infected than horses. A statistically significant difference (p < 0.05) was observed in the prevalence of gastrointestinal nematodes with species and body conditions of the animals. However, no statistically significant difference (p > 0.05) was seen in the prevalence of gastrointestinal nematode parasites between the sex and age of the Equidae. The mean fecal egg count of nematodes revealed that horses (1364.4 ± 483.5) had a more severe infection than donkeys with a statistically significant difference (p < 0.05). The current study determined there was a high prevalence of gastrointestinal nematode parasites in Equidae. Regular deworming, improved housing and nutrition management systems, increased animal owner awareness, and prevention techniques should all be undertaken to minimize the disease's economic burden in the area.
Collapse
|
12
|
Nielsen MK, Littman BA, Orzech SW, Ripley NE. Equine strongylids: Ivermectin efficacy and fecal egg shedding patterns. Parasitol Res 2022; 121:1691-1697. [PMID: 35384503 DOI: 10.1007/s00436-022-07509-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/26/2022] [Indexed: 11/27/2022]
Abstract
Equine cyathostomins are ubiquitous in grazing horses around the world and a main target in parasite control programs. Anthelmintic resistance has been reported with increasing frequency in these parasites over the past decades, and recent findings of fulminant resistance to the macrocyclic lactone class have raised severe concerns. This study aimed to evaluate ivermectin efficacy in cohorts of yearlings and mares present on four different farms in Central Kentucky. Strongylid egg counts were determined with an automated egg counting system, and the percent fecal egg count reduction (FECR) was calculated using a hierarchical Bayesian analysis. Novel principles were used for classification of groups to either no signs of anthelmintic resistance, evidence of resistance, or inconclusive. Furthermore, an epidemiological analysis was conducted evaluating the possible influence of pregnancy status, time of foaling, and year of arrival on mare strongylid egg shedding levels. A total of 102 yearlings and 247 mares were enrolled in the study. Evidence of ivermectin resistance was documented in one group of yearlings with a mean FECR of 91.2% and a 95% credible interval of 84.0-95.8. The results from one mare group and one additional yearling group were deemed inconclusive, whereas the remaining five groups displayed no evidence of ivermectin resistance. Strongylid shedding in the mares was not positively associated with any of the evaluated factors. This study is the first to demonstrate ivermectin resistance in US bred horses, and the findings emphasize the need for routine monitoring of anthelmintic efficacy on horse farms.
Collapse
Affiliation(s)
- Martin K Nielsen
- M. H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA.
| | - Brooke A Littman
- College of Veterinary Medicine, University of California, Davis, CA, USA
| | - Sierra W Orzech
- College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Nichol E Ripley
- M. H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| |
Collapse
|
13
|
Nápravníková J, Várady M, Vadlejch J. Total Failure of Fenbendazole to Control Strongylid Infections in Czech Horse Operations. Front Vet Sci 2022; 9:833204. [PMID: 35265696 PMCID: PMC8899116 DOI: 10.3389/fvets.2022.833204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 01/28/2022] [Indexed: 11/26/2022] Open
Abstract
The control of strongylid infections has become challenging globally for equine practitioners due to the development of anthelmintic resistance. Comprehensive information on anthelmintic resistance in the Czech Republic, however, is still lacking. This study monitored the current efficacy of fenbendazole, pyrantel embonate, ivermectin and moxidectin. Forty-eight of 71 operations met the criteria (≥6 horses with ≥200 eggs per gram), with 969 fecal egg count reduction tests performed. Anthelmintic resistance was evaluated on an operation level based on fecal egg count reduction (FECR) and the lower limit of the 95% credible interval (LLCI) using Bayesian hierarchical models. General anthelmintic efficacy across all operations was assessed by posterior FECRs and the occurrence of sub-zero efficacies. Ivermectin and moxidectin demonstrated excellent efficacy (FECR 99.8–100%; 99.4–100 LLCI) in 45 and 23 operations, respectively, pyrantel embonate demonstrated sufficient efficacy in 15 operations and resistance was suspected in seven operations (FECR 88.1–99.1%; 72.5–98.5 LLCI). Fenbendazole, however, was not effective in a single operation (FECR 19.1–77.8%; 8.1–50.1 LLCI) out of 18. Fenbendazole had the highest probability of sub-zero efficacy (29.1%), i.e., post-treatment fecal egg counts exceeded the pre-treatment counts. Our data indicate an increase in the development of anthelmintic resistance, resulting in total failure of fenbendazole and a reduced efficacy of pyrantel embonate. Introducing advanced approaches of parasite control in the Czech Republic to slow the spread of anthelmintic resistance is thus needed.
Collapse
Affiliation(s)
- Jana Nápravníková
- Department of Zoology and Fisheries, Czech University of Life Sciences Prague, Prague, Czechia
- *Correspondence: Jana Nápravníková
| | - Marián Várady
- Institute of Parasitology, Slovak Academy of Sciences, Košice, Slovakia
| | - Jaroslav Vadlejch
- Department of Zoology and Fisheries, Czech University of Life Sciences Prague, Prague, Czechia
| |
Collapse
|
14
|
Butler AJ, Greenbank H, Parrish R, Nielsen MK, Stoughton WB. Prevalence of anthelmintic resistant cyathostomins in Prince Edward Island, Canada. Vet Parasitol Reg Stud Reports 2021; 26:100629. [PMID: 34879940 DOI: 10.1016/j.vprsr.2021.100629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/06/2021] [Accepted: 08/28/2021] [Indexed: 11/17/2022]
Abstract
Cyathostomins are the most common parasites of adult horses worldwide. Currently, the three classes of anthelmintics used to treat cyathostomin infections includes benzimidazoles, pyrimidines and macrocyclic lactones. However, due to widespread overuse, cyathostomins have developed varying degrees of resistance to all classes of anthelmintics. Fecal egg count reduction tests (FECRT) are currently used to determine the presence of anthelmintic resistance (AR), while egg reappearance periods (ERP) are used to investigate early macrocyclic lactone resistance. The objective of this study was to investigate the prevalence of cyathostomin pyrantel pamoate and ivermectin resistance, and to determine ERP at Prince Edward Island (PEI), Canada horse farms. In addition, fecal cultures and larval identification were performed to evaluate the prevalence of small and large strongyle egg shedding in PEI. Fecal egg counts (FEC) were performed on 270 horses on 14 horse farms across PEI. Horses with≥ 200 eggs per gram (EPG) met the inclusion criteria and were enrolled in the study (n = 101). The median (range) horses per farm was 7.5 (4-11) and 6.0 (4-8) for pyrantel pamoate and ivermectin groups, respectively. Horses were initially treated with 6.6 mg/kg of pyrantel pamoate orally (n = 101). Fecal egg counts were conducted every two weeks for 8 weeks post treatment. Once individual FEC were ≥ 200 EPG, horses were dewormed with 0.2 mg/kg of ivermectin orally (n = 80), and FEC were performed every 2-3 weeks for seven weeks. In this study the ERP was defined as the week the mean FECR were 10% below the initial mean two-week post treatment FECR. Fecal egg count reduction tests and ERP were used to evaluate the efficacy of each anthelmintic. Fecal culture was performed to confirm the shedding of cyathostomin eggs. Fecal egg count reduction tests detected pyrantel pamoate resistance on 5/14 farms. No signs of ivermectin AR were detected, while reappearance of eggs occurred at 4-6 weeks and 7-9 weeks for pyrantel pamoate and ivermectin, respectively. Fecal culture detected large strongyles on 5/14 farms, which accounted for 0.3% of strongyle type eggs cultured. The prevalence of Strongylus vulgaris among individual horses in this study was 2.8% and was detected on 2/14 farms. These findings will allow us to educate owners and veterinarians on appropriate anthelmintic protocols in PEI and can be used as a baseline for continued monitoring of ERP and anthelmintic resistance in this region.
Collapse
Affiliation(s)
- Amanda Jaimie Butler
- Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Ave, Charlottetown, PE C1A 4P3, Canada
| | - Haley Greenbank
- Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Ave, Charlottetown, PE C1A 4P3, Canada
| | - Rebecca Parrish
- Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Ave, Charlottetown, PE C1A 4P3, Canada
| | - Martin K Nielsen
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky. Lexington, KY 40546, USA
| | - William B Stoughton
- Department of Health Management, Atlantic Veterinary College, University of Prince Edward Island, 550 University Ave, Charlottetown, PE C1A 4P3, Canada.
| |
Collapse
|
15
|
Three-year study to evaluate an anthelmintic treatment regimen with reduced treatment frequency in horses on two study sites in Belgium. Vet Parasitol 2021; 298:109538. [PMID: 34364153 DOI: 10.1016/j.vetpar.2021.109538] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 07/23/2021] [Accepted: 07/24/2021] [Indexed: 11/23/2022]
Abstract
In the present study, an anthelmintic treatment regimen with reduced treatment frequency was evaluated in horses on two study sites in Belgium during three consecutive summer pasture seasons. Historically, the horses on both study sites were treated up to 6 times a year with ivermectin (IVM) or up to 4 times a year with moxidectin (MOX), and previous efficacy evaluations indicated a reduced egg reappearance period in some of the treated horses for both IVM (28 days) and MOX (42 days). In the present study, all horses were treated with IVM or MOX in the spring and in autumn. Faecal egg counts (FEC) were conducted every two weeks during the summer pasture season and whenever the individual FEC exceeded 250 eggs per gram of faeces, the specific horse was treated with pyrantel embonate. No increase in parasitic disease over the three-year period of the study was observed. The FEC data collected in the study as well as the age of the animals and local weather data were then imported into a cyathostomin life-cycle model, to evaluate long term effects of the newly applied treatment regimen on the selection pressure for anthelmintic resistance, and compare to the previous high frequency treatment regimen. The model simulations indicated that the whole-herd treatment regimen with at least 4 macrocyclic lactone treatments annually led 2-3 times faster resistance development than any of the alternative treatment regimens evaluated under the specific conditions of these two study sites. Further lowering the treatment frequency or applying even more selective treatments enhanced the delay in resistance development, but to a lesser extent.
Collapse
|
16
|
Gastrointestinal Strongyles Egg Excretion in Relation to Age, Gender, and Management of Horses in Italy. Animals (Basel) 2020; 10:ani10122283. [PMID: 33287298 PMCID: PMC7761647 DOI: 10.3390/ani10122283] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 11/18/2020] [Accepted: 11/30/2020] [Indexed: 01/27/2023] Open
Abstract
Simple Summary Horses worldwide are plagued by gastrointestinal parasites that can lead to severe health problems. The occurrence and intensity of these worm infections vary based on the geographical location, season, and animal management strategies applied. One of these strategies is to monitor the parasite situation in different parts of the world. This research investigates the abundance, proportions, and risk factors of strongyle egg shedding of horses in Italy. Overall, the results showed that approximately 40% of all horses in Italy shed strongyle eggs and that almost 90% of stables have at least one infected animal. In addition, most parasite eggs are found in just a small fraction of the horse population, confirming the need for improved parasite control strategies. Abstract Current equine helminth control strategies play a key role in strongyle epidemiology and anthelmintic resistance and have led to the recommendation for new treatment plans, which include diagnostic and efficacy surveillance. Assessing the equine strongyle distribution patterns would thus be useful and this study describes the strongyle prevalence in the equine population in Italy through coprological analysis and coproculture. In addition, individual data on each animal were collected in order to identify risk factors associated with strongyle egg shedding. Of the total number of stables investigated, 86.4% were found to have at least one positive animal and a 39.5% prevalence of strongyle egg shedding with a mean eggs per gram (EPG) of 245. A total of 80% of the total recorded EPG was shed from 12.8% of positive horses, thus confirming the need for new targeted intervention strategies. Significant differences in parasite prevalence were found based on season, sex, geographical distribution, management and rearing system, and breed. Significantly lower EPG values were found in horses that had received anthelmintic treatment, and macrocyclic lactones (MLs) were the most effective. Lastly, although large strongyles are more pathogenic, horses in Italy are mainly burdened by small strongyles, which pose an important animal health risk requiring continuous parasitological monitoring.
Collapse
|
17
|
Salem SE, Abd El-Ghany AM, Hamad MH, Abdelaal AM, Elsheikh HA, Hamid AA, Saud MA, Daniels SP, Ras R. Prevalence of gastrointestinal nematodes, parasite control practices and anthelmintic resistance patterns in a working horse population in Egypt. Equine Vet J 2020; 53:339-348. [PMID: 32725717 DOI: 10.1111/evj.13325] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/28/2020] [Accepted: 07/16/2020] [Indexed: 01/05/2023]
Abstract
BACKGROUND Anthelmintic resistance is commonly reported in horse populations in developed countries, but evidence in some working horse populations is either lacking or inconclusive. OBJECTIVES To estimate prevalence of GI nematode infections in working horses in Egypt and to evaluate strongyle resistance to ivermectin, doramectin and fenbendazole. STUDY DESIGN Cross-sectional study. METHODS Faecal egg count was performed on 644 working horses from 2 provinces in Egypt. A short questionnaire about horse signalment and worming history was completed for each horse. Horses identified with ≥50 strongyle type egg/g (n = 146) underwent faecal egg count reduction testing (FECRT) following treatment with ivermectin (n = 33), doramectin (n = 33) or fenbendazole (n = 30). Risk factors for strongyle (≥200 egg/g) and Parascaris equorum (>0 egg/g) infection were investigated using multivariable logistic regression analyses. RESULTS The prevalence of low (0-199 epg), medium (200-500 epg) and high (>500 epg) strongyle infection was 88.4%, 5.9% and 5.8%, respectively. P. equorum eggs were detected in 5.1% (n = 33) of horses. Strongyle FECR was 100%, 99.97% and 100% following treatment with ivermectin, doramectin and fenbendazole respectively. Anthelmintic treatment in the 12 months preceding examination was associated with reduced likelihood of strongyle infection (odds ratio [OR] = 0.26, 95% confidence interval [CI] = 0.14, 0.47, P < .001). The likelihood of P. equorum infection was significantly associated with horses' age (OR = 0.78, 95% CI = 0.69, 0.90; P < .001). Male horses were more likely to have P. equorum infection (OR = 2.86, 95% CI = 1.37, 5.93, P = .005). MAIN LIMITATIONS Nonrandomised selection of study areas and larval cultures was unsuccessful for some samples. CONCLUSIONS There were low prevalence of strongyle and P. equorum infection and no evidence of macrocyclic lactones or benzimidazole resistance in strongyles in the studied working horse population.
Collapse
Affiliation(s)
- Shebl E Salem
- Department of Surgery, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Amany M Abd El-Ghany
- Department of Parasitology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Mohamed H Hamad
- Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Ahmed M Abdelaal
- Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Hussein A Elsheikh
- Faculty of Veterinary Medicine, Zagazig University, The Veterinary Clinic, Zagazig, Egypt
| | - Alaa A Hamid
- Department of Fish Diseases and Management, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Mohamed A Saud
- Department of Animal Medicine, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| | - Simon P Daniels
- School of Equine Management and Science, Royal Agricultural University, Cirencester, Gloucestershire, UK
| | - Refaat Ras
- Department of Parasitology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt
| |
Collapse
|
18
|
Imani-Baran A, Abdollahi J, Akbari H, Jafarirad S, Moharramnejad S. Anthelmintic activity of crude powder and crude aqueous extract of Trachyspermum ammi on gastrointestinal nematodes in donkey (Equus asinus): An in vivo study. JOURNAL OF ETHNOPHARMACOLOGY 2020; 248:112249. [PMID: 31557509 DOI: 10.1016/j.jep.2019.112249] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 09/22/2019] [Accepted: 09/23/2019] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Trachyspermum ammi has been used traditionally as a popular ethnobotanical plant in human and animal parasitic infestations. Few scientific studies have been conducted on in vitro anthelmintic activity of T. ammi against various helminths and there is no study on its in vivo/in vitro anthelmintic properties against equine helminths. AIM OF THE STUDY The present study aimed to evaluate in vivo anthelmintic activity of crude powder (CP) and crude aqueous extract (CAE) of T. ammi seeds against gastrointestinal nematodes in the donkey. MATERIALS AND METHODS Thirty donkeys, naturally and severely infected with Strongyle-type nematodes, were randomly divided into six groups and administered orally with graded doses of CP and CAE at single dose as follow: Two groups were treated with 1 and 3 gkg-1 body weight of CP, two groups were treated with CAE at the equivalent dose rate 1 and 3 gkg-1 bw of CP and one group was treated with 200 μgkg-1 bw of Ivermectin 0.2% (Positive Control). One group received no medication (Negative Control). Efficacy was determined by faecal egg count reduction (FECR) test. The faecal samples were taken from the donkeys on days 7, 14 and 28 post-treatments (PT) and the egg per gram (EPG) of faeces was determined for each animal. FECR for donkeys treated with CP, CAE, and Ivermectin 0.2% was calculated on days 7, 14, and 28 PT. In the present study, CAE was analyzed using gas chromatography-mass spectrometry (GC-MS) to determine CAE chemical components. High-performance liquid chromatography (HPLC) using a marker (thymol) was applied to confirm the existence of thymol as an active principle. RESULTS Based on the FECR findings, the maximum FECR (71.2%) was observed in the group treated with CAE3 on day 14 PT, while it was 66.2% for CP3 on the same day. The effects of different treatments (P < 0.001), time (P < 0.001) and their interactions (P < 0.05) on EPG showed a significant difference. A dose-dependent response in the anthelmintic activity of CP and CAE was observed. GC-MS analysis indicated that thymol was the major component of CAE (Area = 45.01%) with the respective peak at retention times (Rt) 10.41 min. On HPLC analysis of CAE, thymol was found to be the major constituent of CAE (Area = 58.76%) with the same Rt at 13.233 min. CONCLUSION The present study indicated that both CP and CAE of T. ammi had the dose-dependent anthelmintic effects. Due to the development of drug resistance against synthetic anti-helminthics, T. ammi seems to be a promising alternative for the treatment and prevention of helminths in livestock.
Collapse
Affiliation(s)
- Abbas Imani-Baran
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
| | - Jalal Abdollahi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
| | - Hamid Akbari
- Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
| | - Saeed Jafarirad
- Research Institute for Fundamental Sciences (RIFS), University of Tabriz, Tabriz, Iran.
| | - Sajjad Moharramnejad
- Crop and Horticultural Science Research Department, Ardabil Agricultural and Natural Resources Research and Education Center, AREEO, Moghan, Iran.
| |
Collapse
|
19
|
Mitchell CJ, O'Sullivan CM, Pinloche E, Wilkinson T, Morphew RM, McEwan NR. Using next-generation sequencing to determine diversity of horse intestinal worms: identifying the equine 'nemabiome'. J Equine Sci 2019; 30:1-5. [PMID: 30944540 PMCID: PMC6445754 DOI: 10.1294/jes.30.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 02/14/2019] [Indexed: 11/01/2022] Open
Abstract
Next-generation sequencing of DNA from nematode eggs has been utilised to give the first account of the equine 'nemabiome'. In all equine faecal samples investigated, multiple species of Strongylidae were detected, ranging from 7.5 (SEM 0.79) with 99+% identity to sequences in the NCBI database to 13.3 (SEM 0.80) with 90+% identity. This range is typical of the number of species described previously in morphological studies using large quantities of digesta per animal. However, the current method is non-invasive; relies on DNA analysis, avoiding the need for specialist microscopy identification; and can be carried out with small samples, providing significant advantages over current methods.
Collapse
Affiliation(s)
- Catriona J Mitchell
- Institute of Biological, Environmental and Rural Sciences, Penglais Campus, Aberystwyth University, SY23 3DA Wales, U.K
| | | | - Eric Pinloche
- Institute of Biological, Environmental and Rural Sciences, Penglais Campus, Aberystwyth University, SY23 3DA Wales, U.K
| | - Toby Wilkinson
- Institute of Biological, Environmental and Rural Sciences, Penglais Campus, Aberystwyth University, SY23 3DA Wales, U.K
| | - Russell M Morphew
- Institute of Biological, Environmental and Rural Sciences, Penglais Campus, Aberystwyth University, SY23 3DA Wales, U.K
| | - Neil R McEwan
- Institute of Biological, Environmental and Rural Sciences, Penglais Campus, Aberystwyth University, SY23 3DA Wales, U.K.,School of Pharmacy and Life Sciences, Garthdee Campus, Robert Gordon University, AB10 7GJ Scotland, U.K
| |
Collapse
|
20
|
Rendle D, Austin C, Bowen M, Cameron I, Furtado T, Hodgkinson J, McGorum B, Matthews J. Equine de-worming: a consensus on current best practice. ACTA ACUST UNITED AC 2019. [DOI: 10.12968/ukve.2019.3.s.3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | - Mark Bowen
- Oakham Veterinary Hospital, Rutland / University of Nottingham
| | | | | | | | | | | |
Collapse
|
21
|
Anthelmintic resistance and novel control options in equine gastrointestinal nematodes. Parasitology 2018; 146:425-437. [DOI: 10.1017/s0031182018001786] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
AbstractControl of equine nematodes has relied on benzimidazoles (BZs), tetrahydropyrimidines and macrocyclic lactones. The intensive use of anthelmintics has led to the development of anthelmintic resistance (AR) in equine cyathostomins and Parascaris equorum. Field studies indicate that BZ and pyrantel resistance is widespread in cyathostomins and there are also increasing reports of resistance to macrocyclic lactones in cyathostomins and P. equorum. The unavailability of reliable laboratory-based techniques for detecting resistance further augments the problem of nematode control in horses. The only reliable test used in horses is the fecal egg count reduction test; therefore, more focus should be given to develop and validate improved methodologies for diagnosing AR at an early stage, as well as determining the mechanisms involved in resistance development. Therefore, equine industry and researchers should devise and implement new strategies for equine worm control, such as the use of bioactive pastures or novel feed additives, and control should increasingly incorporate alternative and evidence-based parasite control strategies to limit the development of AR. This review describes the history and prevalence of AR in equine nematodes, along with recent advances in developing resistance diagnostic tests and worm control strategies in horses, as well as giving some perspective on recent research into novel control strategies.
Collapse
|
22
|
Anthelmintic drugs used in equine species. Vet Parasitol 2018; 261:27-52. [PMID: 30253849 DOI: 10.1016/j.vetpar.2018.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/01/2018] [Accepted: 08/06/2018] [Indexed: 01/16/2023]
Abstract
Internal parasites of horses comprise an intractable problem conferring disease, production and performance losses. Parasitism can rarely be controlled in grazing horses by management alone and anthelmintic drugs have formed the basis of therapy and prophylaxis for the last sixty years. The pharmacology of the anthelmintic drugs available dictate their spectrum of activity and degree of efficacy, their optimal routes of administration and characteristics which prevent some routes of administration, their safety tolerance and potential toxicities and as a consequence of their persistence in the body at effective concentrations their use in epidemiological control programmes. Their use has also resulted in the selection of parasites with genetically controlled characteristics which reduce their susceptibility to treatment, characteristics which are often common to whole chemical classes of anthelmintics. Pharmacological properties also confer compatibility in terms of safety and persistence with other anthelmintic drugs and thus the potential of combinations to treat parasites from different phylogenetic groups such as nematodes, cestodes and trematodes and also the potential by agency of their different molecular mechanisms of action to delay the selection of resistant genes. The major groups of anthelmintics now available, the benzimidazoles (BZD), macrocyclic lactones (MLs) and tetrahydropyrimidines are all highly effective against their targeted parasites (primarily nematodes for BZD's and ML's and cestodes for tetrahydropyrimidines) easily administered orally to horses and are well tolerated with wide margins of safety. Nevertheless, some parasitic stages are inherently less susceptible such as hypobiotic stages of the small strongyles (cyathostomins) and for some such as the adult stages of cyathostomins resistance has developed. Furthermore, for some less common parasites such as the liver fluke unlicensed drugs such as the salicylanilide, closantel have been used. A deep understanding of the pharmacology of anthelmintic drugs is essential to their optimal use in equine species.
Collapse
|
23
|
Salas-Romero J, Gómez-Cabrera KA, Salas JE, Vázquez R, Arenal A, Nielsen MK. First report of anthelmintic resistance of equine cyathostomins in Cuba. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2018; 13:220-223. [PMID: 31014878 DOI: 10.1016/j.vprsr.2018.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 05/22/2018] [Accepted: 07/11/2018] [Indexed: 11/26/2022]
Abstract
Anthelmintic resistance in equine cyathostomins has been described worldwide, with resistance to the benzimidazole class being particularly widespread. The status of anthelmintic efficacy in Cuba has been virtually unknown due to the lack of equine labelled products. One recent report documented suboptimal efficacy levels of extra-label albendazole products against cyathostomins, but it remains unknown to which extent benzimidazole resistance exists in the population. The aim of the present study was to evaluate the anthelmintic efficacy of two benzimidazole products labelled for equines, fenbendazole and oxibendazole. A fecal egg count reduction test (FECRT) was carried out on 132 horses aged 4 months to 18 years in 14 herds, belonging to six provinces. Ten herds exhibited signs of resistance to at least one of the benzimidazoles (mean FECRT<90%). Overall, oxibendazole exhibited higher efficacy than fenbendazole (p = 0.0062), and higher efficacy levels were found in horses never dewormed before compared to those treated within 3-12 months prior to the study (p = 0.0015). Pre-treatment larval cultures revealed the presence of large strongyles and cyathostomin larvae in all herds, while only cyathostomin larvae were detected post treatment. The present work is the first report of anthelmintic resistance in equine cyathostomins in Cuba, and suggests pre-selection for resistant strains by extra-label use of albendazole on the studied farms.
Collapse
Affiliation(s)
- J Salas-Romero
- Facultad de Ciencias Agropecuarias, Universidad de Camagüey Ignacio Agramonte Loynáz, Cuba.
| | - K A Gómez-Cabrera
- Facultad de Ciencias Agropecuarias, Universidad de Camagüey Ignacio Agramonte Loynáz, Cuba
| | - J E Salas
- Escuela Fiscal Unidad Educativa Nacional Napo, Sucumbios, Ecuador
| | - R Vázquez
- Facultad de Ciencias Agropecuarias, Universidad de Camagüey Ignacio Agramonte Loynáz, Cuba
| | - A Arenal
- Facultad de Ciencias Agropecuarias, Universidad de Camagüey Ignacio Agramonte Loynáz, Cuba
| | - M K Nielsen
- M.H. Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY, USA
| |
Collapse
|
24
|
Implementation of Biological Control to the Integrated Control of Strongyle Infection among Wild Captive Equids in a Zoological Park. BIOMED RESEARCH INTERNATIONAL 2018; 2018:4267683. [PMID: 29984232 PMCID: PMC6011151 DOI: 10.1155/2018/4267683] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 04/11/2018] [Accepted: 05/15/2018] [Indexed: 12/02/2022]
Abstract
The integrated control of strongyles was assayed for a period of three years in wild equids (zebras, European donkeys, and African wild asses) captive in a zoo and infected by strongyles. During three years control of parasites consisted of deworming with ivermectin + praziquantel; equids also received every two days commercial nutritional pellets containing a blend of 104 - 105 spores of the fungi Mucor circinelloides + Duddingtonia flagrans per kg meal. Coprological analyses were done monthly to establish the counts of eggs of strongyles per gram of feces (EPG). The reductions in the fecal egg counts (FECR) and in the positive horses (PHR) were calculated fifteen days after deworming; the egg reappearance period (ERP) and the time elapsed from the previous deworming (TPD) were also recorded. Four anthelmintic treatments were administered during the assay, three times throughout the first 2 yrs, and another treatment during the last one. FECR values of 96-100% and 75-100% for the PHR were recorded. The ERP oscillated between eight and twenty-eight weeks, and the TPD ranged from four to eighteen months, increasing to the end of the trial. No side effects were observed in any of the equids. It is concluded that integrated control of strongyles among equids captive in a zoo can be developed by anthelmintic deworming together with the administration of pellets manufactured with spores of parasiticide fungi every two days.
Collapse
|
25
|
Mayaki AM, Mohammed FF, Idris SB. Anthelmintic Resistance and Associated Management Practices in Local Horses in Sokoto Metropolis, Nigeria. MACEDONIAN VETERINARY REVIEW 2018. [DOI: 10.1515/macvetrev-2017-0031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
This study was carried out to assess the management practices used in the control of gastrointestinal (GI) nematodes of horses and to determine the efficacy of three anthelmintics commonly used in Sokoto metropolis. A questionnaire was administered on management practices, while an anthelmintic efficacy test was carried out using 15 horses. The 15 horses were divided into three groups (A, B and C) comprising of 5 each and treated with albendazole, ivermectin and fenbendazole, respectively. The faecal egg count reduction test (FECRT) was used to determine the efficacy and faecal culture was used to determine the parasite species. Majority of the respondents (80%) claimed to have worm control strategies, but only 32.5% used anthelmintics for the control of GI parasites. 62.5% of respondents designed their deworming plan, while only 25% relied on veterinarians. Most of the treatments were done by the horse owners and/or handlers and they largely depended on visual judgement in dosage determination. Their selection of anthelmintics was based on familiarity and 52.5% of the respondents dewormed their horses six times a year using a particular class of anthelmintic or herbal remedies. Resistance against albendazole as well as suspected resistance against fenbendazole by the GI nematodes identified was observed, while ivermectin demonstrated high efficacy against all nematodes isolated. In conclusion, a single dose of subcutaneous injection of ivermectin was highly effective against gastrointestinal parasites in horses, while the worm control strategies employed by respondents enhanced the selection of nematode resistance to albendazole and fenbendazole.
Collapse
Affiliation(s)
- Abubakar Musa Mayaki
- Department of Veterinary Medicine, Faculty of Veterinary Medicine , Usmanu Danfodiyo University , Sokoto , Nigeria
| | - Fatimah Folashade Mohammed
- Department of Veterinary Medicine, Faculty of Veterinary Medicine , Usmanu Danfodiyo University , Sokoto , Nigeria
| | - Sherifat Banke Idris
- Department of Veterinary Pharmacology and Toxicology, Faculty of Veterinary Medicine , Usmanu Danfodiyo University , Sokoto , Nigeria
| |
Collapse
|
26
|
Molena RA, Peachey LE, Di Cesare A, Traversa D, Cantacessi C. Cyathostomine egg reappearance period following ivermectin treatment in a cohort of UK Thoroughbreds. Parasit Vectors 2018; 11:61. [PMID: 29370872 PMCID: PMC5785887 DOI: 10.1186/s13071-018-2638-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 01/10/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In spite of the emergence of populations of drug-resistant cyathostomines worldwide, little is known of parasite species responsible for 'early egg shedding' in cohorts of horses subjected to treatment with widely used anthelmintics, e.g. ivermectin (IVM). In this study, we determined the cyathostomine egg reappearance period (ERP) after IVM treatment in a cohort of yearlings from a large Thoroughbred (TB) stud farm in the United Kingdom, and identified species of cyathostomines with reduced ERP using a combination of fundamental parasitology techniques coupled with advanced molecular tools. METHODS Individual faecal samples were collected from TB yearlings with cyathostomine infection prior to IVM treatment, as well as at 14, 21, 28, 35, 42 and 49 days post-treatment. Faecal egg counts (FEC) were performed for each individual sample for determination of ERPs. In addition, individual larval cultures were performed and representative numbers of third-stage larvae (L3s) harvested from each culture were subjected to molecular species identification via PCR-Reverse Line Blot (RLB). RESULTS Prior to IVM treatment, 11 cyathostomine species were detected in faecal samples from TB horses enrolled in this study, i.e. Cyathostomum catinatum, Cylicostephanus longibursatus, Cylicostephanus goldi, Cylicocyclus nassatus, Cylicostephanus calicatus, Cyathostomum pateratum, Cylicocyclus radiatus, Paraposteriostomum mettami, Coronocyclus labratus, Cylicocyclus insigne and Cylicocyclus radiatus variant A. Of these, eggs of Cya. catinatum, Cys. longibursatus, Cyc. nassatus and Cyc. radiatus could be detected at 28 days post-treatment, while from day 42 onwards, cyathostomine species composition reflected data obtained pre-IVM treatment, with the exception of eggs of Cor. labratus and Cyc. insigne which could no longer be detected post-IVM administration. CONCLUSIONS This study provides valuable data on the occurrence of IVM-resistance in cyathostomines in the UK. Nevertheless, further investigations are needed to shed light on the prevalence and incidence of drug-resistance in this country, as well as other areas of the world where equine trade is substantial.
Collapse
Affiliation(s)
- Rebecca A Molena
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Laura E Peachey
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Angela Di Cesare
- Faculty of Veterinary Medicine, University of Teramo, Località Piano d'Accio, Teramo, Italy
| | - Donato Traversa
- Faculty of Veterinary Medicine, University of Teramo, Località Piano d'Accio, Teramo, Italy
| | - Cinzia Cantacessi
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
| |
Collapse
|
27
|
Rose Vineer H, Vande Velde F, Bull K, Claerebout E, Morgan E. Attitudes towards worm egg counts and targeted selective treatment against equine cyathostomins. Prev Vet Med 2017; 144:66-74. [DOI: 10.1016/j.prevetmed.2017.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 04/30/2017] [Accepted: 05/01/2017] [Indexed: 10/19/2022]
|
28
|
Zak A, Siwinska N, Slowikowska M, Borowicz H, Kubiak K, Hildebrand J, Popiolek M, Niedzwiedz A. Searching for ivermectin resistance in a Strongylidae population of horses stabled in Poland. BMC Vet Res 2017; 13:210. [PMID: 28673347 PMCID: PMC5496315 DOI: 10.1186/s12917-017-1133-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 06/26/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There are no available studies describing the possible resistance of strongyles to ivermectin in horses in Poland. One hundred seventy three horses from nine stud farms from South-Western Poland were studied. The effectiveness of ivermectin was studied on the 14th day after ivermectin administration using the fecal egg count reduction test, and a long-term observation of the egg reappearance period was carried out. The fecal study was carried out using a modified McMaster method, which typically detects 20 eggs per gram of stool. The results were subjected to statistical analysis that enabled quantification of the eggs in the stool samples. RESULTS The study revealed high efficacy of ivermectin on the 14th day after administration without a shortening of the egg reappearance period. CONCLUSION The results indicate that strongyles resistance to ivermectin in Poland is not a serious problem.
Collapse
Affiliation(s)
- A Zak
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland.
| | - N Siwinska
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - M Slowikowska
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - H Borowicz
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - K Kubiak
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| | - J Hildebrand
- Department of Parasitology, Institute of Genetics and Microbiology, University of Wroclaw, ul. S. Przybyszewskiego 63/77, 51-148, Wroclaw, Poland
| | - M Popiolek
- Department of Parasitology, Institute of Genetics and Microbiology, University of Wroclaw, ul. S. Przybyszewskiego 63/77, 51-148, Wroclaw, Poland
| | - A Niedzwiedz
- Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 47, 50-366, Wroclaw, Poland
| |
Collapse
|
29
|
Rosanowski SM, Bolwell CF, Scott I, Sells PD, Rogers CW. The efficacy of Ivermectin against strongyles in yearlings on Thoroughbred breeding farms in New Zealand. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2017; 8:70-74. [DOI: 10.1016/j.vprsr.2017.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 11/01/2016] [Accepted: 02/02/2017] [Indexed: 11/16/2022]
|
30
|
Salas-Romero J, Gomez-Cabrera K, Molento MB, Lyons ET, Delgado A, González L, Arenal A, Nielsen MK. Efficacy of two extra-label anthelmintic formulations against equine strongyles in Cuba. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2017; 8:39-42. [PMID: 31014635 DOI: 10.1016/j.vprsr.2017.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 01/03/2017] [Accepted: 01/27/2017] [Indexed: 10/20/2022]
Abstract
Equine cyathostomin parasites are ubiquitous in grazing horses and have been shown to cause severe inflammatory disease in the large intestine of horses. Decades of intensive anthelmintic therapy have led to widespread anthelmintic resistance in cyathostomins across the world. In Cuba, no anthelmintic products are formulated and sold for equine usage and little is known about anthelmintic efficacy of ruminant and swine formulations used. A strongyle fecal egg count reduction test was used to assess the efficacy of a liquid formulation of ivermectin labelled for use in swine, ruminants and carnivores and a pelleted formulation of albendazole labelled for usage in ruminants. Nine farms in the province Camagüey were enrolled in the study comprising 149 horses in total. Albendazole efficacy was reduced on five farms and with the other four farms having no signs of reduced efficacy. Mean farm efficacies were ranging from 41.7% to 100% on the tested farms. Coprocultures found large strongyle larvae present on all farms, but all larvae identified post-treatment were cyathostomins. Ivermectin was found 100% efficacious on all studied farms. This study provided evidence of reduced albendazole efficacy in the study population. Further work is needed to evaluate whether these findings reflect true resistance or if they are due to pharmacokinetic or pharmacodynamic characteristics of the pelleted formulation tested here.
Collapse
Affiliation(s)
- Josmel Salas-Romero
- Faculty of Agricultural Sciences, University of Camagüey, Ignacio Agramonte Loynáz. Cuba. Carretera de Circunvalación Km 5 1/2, Camagüey 74 650, Cuba.
| | - Karel Gomez-Cabrera
- Faculty of Agricultural Sciences, University of Camagüey, Ignacio Agramonte Loynáz. Cuba. Carretera de Circunvalación Km 5 1/2, Camagüey 74 650, Cuba
| | - Marcelo Beltrão Molento
- Department of Veterinary Medicine, Federal University of Parana, Rua dos Funcionários, 1540 - Laboratório de Doenças Parasitárias, HV Juvevê, 80035-050 Curitiba, PR, Brasil
| | - Eugene T Lyons
- Department of Veterinary Science, University of Kentucky, Gluck Equine Research Center, Lexington, KY 40546-0099, USA
| | - Anay Delgado
- Faculty of Agricultural Sciences, University of Camagüey, Ignacio Agramonte Loynáz. Cuba. Carretera de Circunvalación Km 5 1/2, Camagüey 74 650, Cuba
| | - Luis González
- Faculty of Agricultural Sciences, University of Camagüey, Ignacio Agramonte Loynáz. Cuba. Carretera de Circunvalación Km 5 1/2, Camagüey 74 650, Cuba
| | - Amilcar Arenal
- Faculty of Agricultural Sciences, University of Camagüey, Ignacio Agramonte Loynáz. Cuba. Carretera de Circunvalación Km 5 1/2, Camagüey 74 650, Cuba
| | - Martin K Nielsen
- Department of Veterinary Science, University of Kentucky, Gluck Equine Research Center, Lexington, KY 40546-0099, USA
| |
Collapse
|
31
|
Tzelos T, Barbeito JSG, Nielsen MK, Morgan ER, Hodgkinson JE, Matthews JB. Strongyle egg reappearance period after moxidectin treatment and its relationship with management factors in UK equine populations. Vet Parasitol 2017; 237:70-76. [PMID: 28249767 DOI: 10.1016/j.vetpar.2017.02.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 02/13/2017] [Accepted: 02/18/2017] [Indexed: 11/29/2022]
Abstract
Parasitic nematodes, particularly cyathostomins, are ubiquitous in grazing horses world-wide. Considerable burdens of cyathostomin larvae can encyst in the large intestinal wall. The most recommended treatment against these pathogenic stages is moxidectin. Information is required on how effective moxidectin is against cyathostomin populations in different regions. The objectives here were to determine the efficacy of moxidectin treatment and estimate the strongyle egg reappearance period (ERP) after treatment in several equine populations, to confirm the type of strongyle nematodes present and to identify other (i.e. management) factors associated with shortened ERP. Eight yards were recruited and moxidectin in combination with praziquantel administered to all horses (n=261). Faecal egg count (FEC) analysis was performed at weeks 0, 2, 6, 10 and 12 after treatment to determine efficacy and ERP. The ERP was estimated using two previously published methods. Morphological identification of cultured third stage larvae from the sample population was compared to a Strongylus vulgaris-specific end-point PCR to examine the presence of S. vulgaris in samples before and after treatment. Strongyle egg shedding patterns were also compared to worm management practices at each site. At 2 weeks post-treatment, moxidectin was highly effective (faecal egg count reduction range, 99.9-100%). The strongyle ERP ranged from 6 weeks to >12 weeks depending on the calculation method applied. Only cyathostomin larvae were detected by morphological identification. The results from the coprocultures and PCR showed that S. vulgaris was absent before and after treatment. Analysis revealed that regular faecal removal from pasture was associated with lower average FEC and lower prevalence of egg shedding.
Collapse
Affiliation(s)
- Thomas Tzelos
- Moredun Research Institute, Pentlands Science Park, Edinburgh, EH26 0PZ, UK.
| | - Jessica S G Barbeito
- University of Lisbon, Avenida da Universidade Técnica, 1300-477 Lisbon, Portugal
| | - Martin K Nielsen
- Department of Veterinary Science, M.H. Gluck Equine Research Center, University of Kentucky, Lexington, KY, USA
| | - Eric R Morgan
- University of Bristol, Langford House, Langford, Bristol BS40 5DU, UK
| | - Jane E Hodgkinson
- Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7ZJ, UK
| | | |
Collapse
|
32
|
Diseases of the Alimentary Tract. Vet Med (Auckl) 2017. [PMCID: PMC7167529 DOI: 10.1016/b978-0-7020-5246-0.00007-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
33
|
Equine Cyathostominae can develop to infective third-stage larvae on straw bedding. Parasit Vectors 2016; 9:478. [PMID: 27581072 PMCID: PMC5006614 DOI: 10.1186/s13071-016-1757-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 08/15/2016] [Indexed: 11/24/2022] Open
Abstract
Background Domesticated grazing animals including horses and donkeys are frequently housed using deep litter bedding systems, where it is commonly presumed that there is no risk of infection from the nematodes that are associated with grazing at pasture. We use two different approaches to test whether equids could become infected with cyathostomines from the ingestion of deep litter straw bedding. Methods Two herbage plot studies were performed in horticultural incubators set up to simulate three straw bedding scenarios and one grass turf positive control. Faeces were placed on 16 plots, and larval recoveries performed on samples of straw/grass substrate over 2- to 3-week periods. Within each incubator, a thermostat was set to maintain an environmental temperature of approximately 10 °C to 20 °C. To provide further validation, 24 samples of straw bedding were collected over an 8-week period from six barns in which a large number of donkeys were housed in a deep litter straw bedding system. These samples were collected from the superficial bedding at 16 sites along a “W” route through each barn. Results No infective larvae were recovered from any of the plots containing dry straw. However, infective cyathostomine larvae were first detected on day 8 from plots containing moist straw. In the straw bedding study, cyathostomine larvae were detected in 18 of the 24 samples. Additionally, in the two barns which were sampled serially, the level of larval infectivity generally increased from week to week, except when the straw bedding was removed and replaced. Conclusions We have demonstrated that equine cyathostomines can develop to infective larvae on moist straw bedding. It is therefore possible for a horse or donkey bedded in deep litter straw to become infected by ingesting the contaminated straw. This has implications for parasite control in stabled equids and potentially in housed ruminants, and further investigation is required in order to establish the relative infective pressure from pasture versus straw bedding. Electronic supplementary material The online version of this article (doi:10.1186/s13071-016-1757-1) contains supplementary material, which is available to authorized users.
Collapse
|
34
|
Papaya latex supernatant has a potent effect on the free-living stages of equid cyathostomins in vitro. Vet Parasitol 2016; 228:23-29. [PMID: 27692327 DOI: 10.1016/j.vetpar.2016.07.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 07/28/2016] [Accepted: 07/31/2016] [Indexed: 11/21/2022]
Abstract
The control of equid gastrointestinal nematodes in developed countries, in particular the cyathostomins, is threatened by high levels of anthelmintic resistance. In recent years, there has been increasing interest in the evaluation of traditional 'ethnoveterinary' medicines as alternatives to chemical anthelmintics. The cysteine proteinases (CPs), a group of enzymes derived from fruits such as papaya (Carica papaya), pineapple (Ananas comosus) and figs (Ficus spp.), have shown good efficacy against adult stages of a range of parasitic nematodes, in vitro and in vivo. The efficacy of CPs against cyathostomins remains to be explored. In this study, the efficacy of a crude preparation of CPs, papaya latex supernatant (PLS), against the free-living stages of cyathostomins was evaluated using two in vitro tests, the egg hatch test (EHT) and the larval migration inhibition test (LMIT). It was demonstrated that PLS had a potent effect in the EHT, with EC-50 values in the range of 0.12-0.22μM. At concentrations above 6.25μM the eggs did not develop, below this concentration the L1 developed but they lost integrity of the cuticle upon hatching. These effects were inhibited by pre-incubation of PLS with the CP inhibitor L-trans-epoxysuccinyl-l-leucylamido-(4-guanidino butane) (E64), indicating that CPs were responsible for the anti-parasitic activity. A dose-dependent inhibition of migration of third stage larvae (L3) in the LMIT was demonstrated at higher concentrations of PLS, with EC-50 values in the range of 67.35-106.31μM. Incubation of PLS with E64 prior to use in the LMIT did not reverse the anti-migratory effect, suggesting that CPs were not responsible for the reduced migration of cyathostomin L3 and that PLS also contains an additional active compound. This is the first report of PLS and/or CPs showing activity against the free-living stages of a parasitic helminth. In addition, it suggests that cyathostomins are highly sensitive to the effects of CPs and further evaluation of their efficacy against parasitic stages and in vivo are strongly indicated.
Collapse
|
35
|
Lyons ET, Dorton AR, Tolliver SC. Evaluation of activity of fenbendazole, oxibendazole, piperazine , and pyrantel pamoate alone and combinations against ascarids, strongyles, and strongyloides in horse foals in field tests on two farms in Central Kentucky in 2014 and 2015. VETERINARY PARASITOLOGY- REGIONAL STUDIES AND REPORTS 2016; 3-4:23-26. [PMID: 31014495 DOI: 10.1016/j.vprsr.2016.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 04/18/2016] [Accepted: 05/21/2016] [Indexed: 11/24/2022]
Abstract
Activity of fenbendazole (FBZ), oxibendazole (OBZ), piperazine (PIP) and pyrantel pamoate (PRT) alone and combinations of OBZ and PIP and of OBZ and PRT was evaluated against parascarids, strongyles and strongyloides in horse foals (n=281).This was on two farms - Farm A - mixed light-horses (n=26) and Farm B-Thoroughbreds (n=255) - in Central Kentucky in field tests in 2014 and 2015. Foals on both farms were treated one to three times each; an exception was that seven foals on Farm A were nontreated controls. Before treatment, the foals on Farm A were all weighed on scales but weights for Farm B were estimated. Evaluation of the anthelmintics was by recording the number of foals passing specific types of nematode eggs before and after treatment using qualitative and/or quantitative (EPG) methods. Results are: 1) ascarids (parascarids) - efficacy was excellent for OBZ, PIP, OBZ-PIP, and OBZ-PRT; likewise for PRT for one group (in 2014) of Farm A foals but not another group (2015) there. FBZ was inactive against these parasites. 2) strongyles - activity was lacking or incomplete for all of the compounds alone or in combination; it was the best for OBZ-PIP, OBZ-PRT and PRT alone. 3) strongyloides - data indicated no or incomplete activity; it was highest for OBZ and OBZ-PIP. The level of drug activity against parasites in Farm B foals may in some instances have been different if exact rather than estimated body weights had been obtained before treatment like for Farm A foals.
Collapse
Affiliation(s)
- Eugene T Lyons
- Department of Veterinary Science, University of Kentucky, Gluck Equine Research Center, Lexington, KY 40546-0099, USA.
| | - Alan R Dorton
- Private Equine Veterinary Practitioner, Versailles, KY, USA
| | - Sharon C Tolliver
- Department of Veterinary Science, University of Kentucky, Gluck Equine Research Center, Lexington, KY 40546-0099, USA
| |
Collapse
|
36
|
Lightbody KL, Davis PJ, Austin CJ. Validation of a novel saliva-based ELISA test for diagnosing tapeworm burden in horses. Vet Clin Pathol 2016; 45:335-46. [PMID: 27218436 DOI: 10.1111/vcp.12364] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Tapeworm infections pose a significant threat to equine health as they are associated with clinical cases of colic. Diagnosis of tapeworm burden using fecal egg counts (FECs) is unreliable, and, although a commercial serologic ELISA for anti-tapeworm antibodies is available, it requires a veterinarian to collect the blood sample. A reliable diagnostic test using an owner-accessible sample such as saliva could provide a cost-effective alternative for tapeworm testing in horses, and allow targeted deworming strategies. OBJECTIVES The purpose of the study was to statistically validate a saliva tapeworm ELISA test and compare to a tapeworm-specific IgG(T) serologic ELISA. METHODS Serum samples (139) and matched saliva samples (104) were collected from horses at a UK abattoir. The ileocecal junction and cecum were visually examined for tapeworms and any present were counted. Samples were analyzed using a serologic ELISA and the saliva tapeworm test. The test results were compared to tapeworm numbers and the various data sets were statistically analyzed. RESULTS Saliva scores had strong positive correlations with both infection intensity (0.74) and serologic results (Spearman's rank coefficients; 0.74 and 0.86, respectively). The saliva tapeworm test was capable of identifying the presence of one or more tapeworms with 83% sensitivity and 85% specificity. Importantly, no high-burden (more than 20 tapeworms) horses were misdiagnosed. CONCLUSIONS The saliva tapeworm test has statistical accuracy for detecting tapeworm burdens in horses with 83% sensitivity and 85% specificity, similar to those of the serologic ELISA (85% and 78%, respectively).
Collapse
|
37
|
An evidence-based approach to the evaluation of ethnoveterinary medicines against strongyle nematodes of equids. Vet Parasitol 2015; 210:40-52. [DOI: 10.1016/j.vetpar.2015.03.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 03/12/2015] [Accepted: 03/13/2015] [Indexed: 11/18/2022]
|
38
|
Nielsen MK, Jacobsen S, Olsen SN, Bousquet E, Pihl T. Nonstrangulating intestinal infarction associated withStrongylus vulgarisin referred Danish equine cases. Equine Vet J 2015; 48:376-9. [DOI: 10.1111/evj.12422] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/02/2015] [Indexed: 11/26/2022]
Affiliation(s)
- M. K. Nielsen
- Department of Veterinary Science; M.H. Gluck Equine Research Center; University of Kentucky; Lexington USA
| | - S. Jacobsen
- Department of Large Animal Sciences; University of Copenhagen; Denmark
| | - S. N. Olsen
- Department of Large Animal Sciences; University of Copenhagen; Denmark
| | | | - T. Pihl
- Department of Large Animal Sciences; University of Copenhagen; Denmark
| |
Collapse
|
39
|
Matthews JB. Anthelmintic resistance in equine nematodes. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2014; 4:310-5. [PMID: 25516842 PMCID: PMC4266799 DOI: 10.1016/j.ijpddr.2014.10.003] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Overuse of anthelmintics in horses has reduced disease, but led to widespread resistance. Benzimidazole, tetrahydropyrimidine and macrocyclic lactone resistance in cyathostomins. Ivermectin resistance common in Parascaris equorum. Good grazing management must be integrated with targeted anthelmintic treatments. Progress in novel diagnostics to define pre-patent worm levels is described.
Anthelmintics have been applied indiscriminately to control horse nematodes for over 40 years. Three broad-spectrum anthelmintic classes are currently registered for nematode control in horses: benzimidazoles (fenbendazole, oxibendazole), tetrahydropyrimidines (pyrantel) and macrocyclic lactones (ivermectin, moxidectin). Generally, control strategies have focused on nematode egg suppression regimens that involve the frequent application of anthelmintics to all horses at intervals based on strongyle egg reappearance periods after treatment. The widespread use of such programmes has substantially reduced clinical disease, especially that associated with large strongyle species; however, high treatment frequency has led to considerable selection pressure for anthelmintic resistance, particularly in cyathostomin species. Field studies published over the last decade indicate that benzimidazole resistance is widespread globally in cyathostomins and there are also many reports of resistance to pyrantel in these worms. Cyathostomin resistance to macrocyclic lactone compounds is emerging, principally measured as a reduction in strongyle egg reappearance time observed after treatment. Ivermectin resistance is a further concern in the small intestinal nematode, Parascaris equorum, an important pathogen of foals. These issues indicate that horse nematodes must now be controlled using methods less dependent on anthelmintic use and more reliant on management practices designed to reduce the force of infection in the environment. Such strategies include improved grazing management integrated with targeted anthelmintic administration involving faecal egg count (FEC)-directed treatments. The latter require that the supporting diagnostic tests available are robust and practically applicable. Recent research has focused on maximising the value of FEC analysis in horses and on optimizing protocols for anthelmintic efficacy testing. Other studies have sought to develop diagnostics that will help define levels of pre-patent infection. This review describes recent advances in each of these areas of research.
Collapse
Affiliation(s)
- Jacqueline B Matthews
- Moredun Research Institute, Pentlands Science Park, Edinburgh, Midlothian, EH26 0PZ, UK
| |
Collapse
|
40
|
Mason ME, Voris ND, Ortis HA, Geeding AA, Kaplan RM. Comparison of a single dose of moxidectin and a five-day course of fenbendazole to reduce and suppress cyathostomin fecal egg counts in a herd of embryo transfer-recipient mares. J Am Vet Med Assoc 2014; 245:944-51. [PMID: 25285937 DOI: 10.2460/javma.245.8.944] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To compare larvicidal regimens of fenbendazole and moxidectin for reduction and suppression of cyathostomin fecal egg counts (FEC) in a transient herd of embryo transfer-recipient mares. DESIGN Randomized, complete block, clinical trial. ANIMALS 120 mares from 21 states, residing on 1 farm. PROCEDURES An initial fecal sample was collected from each mare; mares with an FEC ≥ 200 eggs/g were assigned to treatment groups. Eighty-two horses received fenbendazole (10.0 mg/kg [4.5 mg/lb], PO, q 24 h for 5 days) or moxidectin (0.4 mg/kg [0.18 mg/lb], PO, once); FEC data were analyzed 14, 45, and 90 days after treatment. RESULTS Mean FEC reduction was 99.9% for moxidectin-treated mares and 41.9% for fenbendazole-treated mares 14 days after treatment. By 45 days, mean FEC of fenbendazole-treated mares exceeded pretreatment counts; however, FECs of moxidectin-treated mares remained suppressed below pretreatment values for the duration of the 90-day study. Fecal egg counts were significantly different between groups at 14, 45, and 90 days after treatment. CONCLUSIONS AND CLINICAL RELEVANCE Failure of the 5-day regimen of fenbendazole to adequately reduce or suppress FEC suggested inadequate adulticidal and larvicidal effects. In contrast, a single dose of moxidectin effectively reduced and suppressed FEC for an extended period. Given the diverse geographic origins of study mares, these results are likely representative of cyathostomin-infected mares in much of the United States, confirming previous findings indicating that fenbendazole resistance in cyathostomins is widespread and that moxidectin remains an effective treatment for control of these important parasites.
Collapse
Affiliation(s)
- Maren E Mason
- College of Veterinary Medicine, University of Georgia, Athens, GA 30302
| | | | | | | | | |
Collapse
|
41
|
Geurden T, van Doorn D, Claerebout E, Kooyman F, De Keersmaecker S, Vercruysse J, Besognet B, Vanimisetti B, di Regalbono AF, Beraldo P, Di Cesare A, Traversa D. Decreased strongyle egg re-appearance period after treatment with ivermectin and moxidectin in horses in Belgium, Italy and The Netherlands. Vet Parasitol 2014; 204:291-6. [DOI: 10.1016/j.vetpar.2014.04.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 04/09/2014] [Accepted: 04/12/2014] [Indexed: 11/26/2022]
|
42
|
Anthelmintic efficacy on UK Thoroughbred stud farms. Int J Parasitol 2014; 44:507-14. [PMID: 24746779 DOI: 10.1016/j.ijpara.2014.03.006] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 03/17/2014] [Accepted: 03/18/2014] [Indexed: 11/23/2022]
Abstract
Anthelmintic drugs have been applied indiscriminately to control horse nematodes for over 40 years. We undertook a comprehensive study to investigate efficacy of the four available broad-spectrum anthelmintic drugs on 16 Thoroughbred stud farms using the faecal egg count reduction test. Efficacy against strongyles was determined by calculating the percentage of reduction in faecal egg count between the group mean at Day 0 and Days 14-17 post-treatment and the 95% lower confidence intervals estimated by non-parametric bootstrapping. Individual strongyle faecal egg count reduction tests (n=429) were performed in which 179, 131, 89 and 30 horses were administered ivermectin, moxidectin, pyrantel and fenbendazole, respectively. Moxidectin was efficacious in all tests (faecal egg count reduction range: 99.8-100%; 95% lower confidence intervals range: 96.8-100%) and reduced efficacy of ivermectin (faecal egg count reduction range: 85.7-100%; 95% lower confidence intervals range: 65-100%) was observed in one group of yearlings. Reduced pyrantel efficacy was observed in five groups of yearlings (faecal egg count reduction range: 0-73%; 95% lower confidence intervals range: 0-59.5%), but pyrantel was found to be efficacious when administered to mares (faecal egg count reduction range: 98-99.4%; 95% lower confidence intervals range: 91.8-99.3%). Low efficacy of fenbendazole was always observed (faecal egg count reduction range: 0.4-41%; 95% lower confidence intervals not calculable). Two further methods for estimating efficacy were applied and outputs obtained using all methodologies were in agreement. Efficacy against Parascaris equorum was assessed on four farms: fenbendazole had acceptable efficacy (faecal egg count reduction range: 97.5-99.9%; 95% lower confidence intervals range: 96.3-99.1%), but reduced efficacy of ivermectin was observed (faecal egg count reduction range: 25.5-91.2%; 95% lower confidence intervals range: 6.7-82.4%). Strongyle faecal egg count were analysed at approximately 2 week intervals for up to 12 weeks after anthelmintic drug administration to determine the egg reappearance period for moxidectin, ivermectin and pyrantel. The egg reappearance period for all three anthelmintic drugs was shorter than previously observed. Overall, our results indicate that ivermectin and moxidectin administration provided acceptable efficacy at 14 days; however, egg reappearance period results suggest that these products are working less effectively than measured previously. As shortened egg reappearance period is believed to be an early indicator of resistance, this highlights the issue of impending multi-drug resistance in strongyles on stud farms.
Collapse
|
43
|
Anthelmintic resistance in important parasites of horses: Does it really matter? Vet Parasitol 2014; 201:1-8. [DOI: 10.1016/j.vetpar.2014.01.004] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 01/03/2014] [Accepted: 01/08/2014] [Indexed: 11/20/2022]
|
44
|
Affiliation(s)
- J. B. Matthews
- Disease Control; Moredun Research Institute; Edinburgh UK
| |
Collapse
|
45
|
Lester HE, Matthews JB. Faecal worm egg count analysis for targeting anthelmintic treatment in horses: Points to consider. Equine Vet J 2013; 46:139-45. [DOI: 10.1111/evj.12199] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 10/05/2013] [Indexed: 11/28/2022]
|
46
|
Lester HE, Bartley DJ, Morgan ER, Hodgkinson JE, Stratford CH, Matthews JB. A cost comparison of faecal egg count-directed anthelmintic delivery versus interval programme treatments in horses. Vet Rec 2013; 173:371. [PMID: 24068698 DOI: 10.1136/vr.101804] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- H E Lester
- Department of Disease Control, Moredun Research Institute, Edinburgh EH26 0PZ, UK
| | | | | | | | | | | |
Collapse
|
47
|
Wright S. Highlights of recent clinically relevant papers. EQUINE VET EDUC 2013. [DOI: 10.1111/eve.12074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|