Fecal Egg Count (FEC) is a diagnostic tool used to quantify the number of parasite eggs present in a horse's feces. This measure is primarily employed to assess the burden of gastrointestinal parasites, such as strongyles and ascarids, in equine populations. FEC is instrumental in informing parasite management strategies, including the timing and effectiveness of anthelmintic treatments. The process involves collecting a fecal sample from the horse, preparing it in a laboratory setting, and examining it under a microscope to count the eggs. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and implications of fecal egg count in equine parasitology.
Bartosik J, Łojek J, Długosz E, Górski P, Zygner W.Tapeworm infections in Konik Polski horses from Biebrza National Park were investigated in this study. Faecal samples were collected 10 times: in 2012 - 1 time, in 2013 - 4 times, in 2014 - 4 times and in 2015 - 1 time. In total, 162 faecal samples were collected and tested. Faecal egg counts (FECs) method was used in the study. Positive samples with cestode eggs were noted only twice - in October 2012 and December 2013 in two adult mares (9 and 11 years old). The determined prevalence was surprisingly low comparing to other studies, 4.3% in October 2013 and 28.5% in December 2013. Parasite ge...
Scala A, Tamponi C, Sanna G, Predieri G, Dessì G, Sedda G, Buono F, Cappai MG, Veneziano V, Varcasia A.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 inves...
Villa-Mancera A, Aldeco-Pérez M, Molina-Mendoza P, Hernández-Guzmán K, Figueroa-Castillo JA, Reynoso-Palomar A.The aims of this study were to determine the prevalence of gastrointestinal nematodes (GIN) in horses, donkeys and mules and its associations with age, sex and climatic factors (derived from satellite data) to identify the potential risk factors of different climate regions in four Mexican states. From May 2017 to April 2018, a total of 560 farm owners or managers answered the questionnaire, and the data were used to establish three Köppen climate classes (tropical, dry, temperate). The overall prevalence of GIN parasites in equines was 77.9% (436 out of 560). The highest percentage of GIN wa...
Nielsen MK, Gee EK, Hansen A, Waghorn T, Bell J, Leathwick DM.Strongylid and ascarid parasites are omnipresent in equine stud farms, and ever-increasing levels of anthelmintic resistance are challenging the industry with finding more sustainable and yet effective parasite control programs. Objective: To evaluate egg count levels, bodyweight and equine health under defined parasite control protocols in foals and mares at two Standardbred and two Thoroughbred stud farms. Methods: Longitudinal randomised field trial. Methods: A total of 93 foals were enrolled and split into two treatment groups, and 99 mares were enrolled and assigned to three treatment gro...
Poissant J, Gavriliuc S, Bellaw J, Redman EM, Avramenko RW, Robinson D, Workentine ML, Shury TK, Jenkins EJ, McLoughlin PD, Nielsen MK, Gilleard JS.Horses are ubiquitously infected by a diversity of gastro-intestinal parasitic helminths. Of particular importance are nematodes of the family Strongylidae, which can significantly impact horse health and performance. However, knowledge about equine strongyles remains limited due to our inability to identify most species non-invasively using traditional morphological techniques. We developed a new internal transcribed spacer 2 (ITS2) DNA metabarcoding 'nemabiome' assay to characterise mixed strongyle infections in horses and assessed its performance by applying it to pools of infective larvae ...
The aim of this study was to investigate the difference in Fecal Egg Counts (FEC) with regard to group size, age, sex and body condition of wild free-roaming Przewalski's horses in the Chernobyl Exclusion Zone (Ukraine), across different seasons, over a five-year period (2014 - 2018). We hypothesized that horses from larger group sizes would have higher faecal egg counts (FECs). The relationship between FECs and the year and season of sample collection, and age, sex and group size of the horses was analyzed. Generalized linear model using positive strongylid FEC`s as a variable response, was u...
Arfuso F, Bazzano M, Brianti E, Gaglio G, Passantino A, Tesei B, Laus F.The increasing levels of anthelmintic resistance together with the restrictions in the use of drugs in food producing animals have enforced the search for sustainable alternative approaches for parasite control. The current study aimed to investigate the safety and the efficacy of a commercially available phytotherapic formulation against gastrointestinal strongyles in donkeys. Twenty-two Ragusana jennies (2.6 ± 0.5 years old) were assigned to two equal groups. One group was treated with two doses of a phytotherapic supplement Paraxitebio® containing , and , 14 days apart (Group A). One grou...
Nielsen MK, Banahan M, Kaplan RM.Anthelmintic resistance in equine cyathostomins is both widespread and highly prevalent in the benzimidazole and tetrahydropyrimidine classes; however, reports of resistance to macrocyclic lactone (ML) drugs are sparse and sporadic. This study reports a case of clear ML resistance in a group of Thoroughbred yearlings imported from Ireland to the US in 2019. Fecal egg count reduction (FECR) following ivermectin administered in February 2020 demonstrated 100% reduction in the US bred yearlings, but 93.5%, 70.5%, and 74.5% reduction in three groups of the imported yearlings. The two former groups...
Fesseha H, Mathewos M, Kidanemariam F.Gastrointestinal helminth parasite infection is a major influencing factor against profitability of working equines all over the world. Objective: A study was conducted from October 2016 to May 2017 in and around Hosaena to determine the efficacy of benzimidazole (BZ) and avermectin (AVM) chemical groups against strongyle nematodes in working donkeys. Methods: A total of 230 donkeys from Hosaena, Soro, Anlemo, and Gombora were randomly allocated into 5 groups of 46 donkeys in each group. All groups, except group 1 (control), were treated with ivermectin 1%, ivertong 10%, fenbendazole, and Fena...
Salem SE, Abd El-Ghany AM, Hamad MH, Abdelaal AM, Elsheikh HA, Hamid AA, Saud MA, Daniels SP, Ras R.Anthelmintic resistance is commonly reported in horse populations in developed countries, but evidence in some working horse populations is either lacking or inconclusive. Objective: To estimate prevalence of GI nematode infections in working horses in Egypt and to evaluate strongyle resistance to ivermectin, doramectin and fenbendazole. Methods: 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 ...
Cain JL, Slusarewicz P, Rutledge MH, McVey MR, Wielgus KM, Zynda HM, Wehling LM, Scare JA, Steuer AE, Nielsen MK.Fecal egg counts are the cornerstone of equine parasite control programs. Previous work led to the development of an automated, image-analysis-based parasite egg counting system. The system has been further developed to include an automated reagent dispenser unit and a custom camera (CC) unit that generates higher resolution images, as well as a particle shape analysis (PSA) algorithm and machine learning (ML) algorithm. The first aim of this study was to conduct a comprehensive comparison of method precision between the original smartphone (SP) unit with the PSA algorithm, CC/PSA, CC/ML, and ...
Tyson F, Dalesman S, Brophy PM, Morphew RM.Faecal egg counts (FECs) are the standard method of diagnosing the level of parasitic helminth egg shedding in horses and other grazing animals. Testing before treatment is an important factor in slowing the appearance of anthelmintic resistance in nematode parasites. The FECPAK, optimised for livestock, is reported to allow owners to perform FECs on their own animals without the need for a separate microscope or any specialist knowledge by tapping into remote expertise. However, the performance of the FECPAK has yet to be assessed for equids. Therefore, a comparison of the FECPAK (G2) method ...
Studzińska MB, Sallé G, Roczeń-Karczmarz M, Szczepaniak K, Demkowska-Kutrzepa M, Tomczuk K.Parascaris spp. are major gastro-intestinal nematodes that infect foals and can lead to respiratory symptoms, poor growth, and in some cases obstruction of the small intestine and death. Ivermectin resistance has been reported for Parascaris spp. in many countries. In Poland, the knowledge of the level of resistance against ivermectin in Parascaris spp. is limited. The aim of this study was to examine the efficacy of ivermectin against Parascaris spp. in foals from south-eastern Poland. Foals (n = 225 = reared in 7 stud farms) were treated orally with ivermectin paste. Faecal samples w...
Ivermectin (IVM) is an anthelmintic compound commonly used off-label in mules due to its broad-spectrum of activity. Despite the general use of IVM in mules with the same dose and route of administration licensed for horses, significant pharmacokinetic differences might exist between horses and mules, as already observed for donkeys. The aim of the present study was to evaluate the pharmacokinetic profile and anthelmintic efficacy of an oral paste of IVM in mules naturally infected with cyathostomins. Fifteen adult mules with fecal egg counts (FEC) ≥200 eggs per gram (EPG), with exclusive pr...
Hedberg-Alm Y, Penell J, Riihimäki M, Osterman-Lind E, Nielsen MK, Tydén E.All grazing horses are exposed to intestinal parasites, which have the potential to cause gastrointestinal disease. In Sweden, there is a concern about an increase in parasite-related equine gastrointestinal disease, in particular , since the implementation of prescription-only anthelmintics approximately 10 years ago. In a prospective case-control study, parasitological status, using fecal analyses for strongyle egg counts, the presence of eggs and Polymerase chain reaction (PCR) as well as serology for , were compared between horses presenting with or without gastrointestinal disease at a ...
Kuzmina ТА, Zvegintsova NS, Yasynetska NI, Kharchenko VA.Resistance of strongylids in domestic horses to benzimidazole anthelmintics (BZ) has been detected worldwide; however, information on the presence of BZ-resistance in wild equids has not been published to date. The purpose of this study was to analyze the manifestations of the BZ resistance in strongylids in domestic and wild equids kept in the Askania Nova Biosphere Reserve, Ukraine. Four species of equids: domestic horses and Shetland ponies (Equus caballus), donkeys (E. asinus), plains zebras (E. burchelli) and Grévy’s zebras (E. grevyi) kept under semi-free conditions were examined usin...
Cooper LG, Caffe G, Cerutti J, Nielsen MK, Anziani OS.Macrocyclic lactones are the most widely used drugs for the control of gastrointestinal nematodes of horses in Argentina. Ivermectin and moxidectin are used as broad spectrum anthelmintics and although there are several international reports on the resistance of Parascaris spp., the resistance status of the local nematode population is largely unknow. This report informs a case of suboptimal efficacy to both drugs to control Parascaris spp in foals in central Argentina. In February 2018, routine fecal parasite egg counts showed a moderate-high number of Parascaris spp eggs (mean = 680 eggs p...
Vera JHS, Fachiolli DF, Ramires LM, de Lima Saes I, Yamada PH, Gonçalves JA, de Oliveira K, do Amarante AFT, de Soutello RVG.The objectives of the present study were to evaluate the efficacy of three anthelmintic drugs, i.e. fenbendazole, ivermectin and moxidectin; to determine the genera and species of the most abundant strongyles; and to investigate parasite control measures used in herds of horses in the western region of the state of São Paulo, Brazil. This study was onducted between February and December 2013 on 10 farms in this region. Coprological evaluations were conducted for counting the numbers of eggs per gram of feces (EPG) and coprocultures were made in order to identify third-stage larvae (L3) of str...
Wilkes EJA, Heller J, Raidal SL, Woodgate RG, Hughes KJ.Information regarding parasite control practices currently used on Thoroughbred and Standardbred studs in Australia is lacking. Anthelmintic resistance (AR) is a global problem which has implications for equine health and welfare. Objective: To identify parasite control practices currently used on horse studs in Australia and investigate the frequency of use of management factors that have been associated with the likelihood of promoting or delaying AR. Methods: Questionnaire study of equine parasite control on Thoroughbred and Standardbred studs in Australia. Methods: An online questionnaire ...
Jenkins E, Backwell AL, Bellaw J, Colpitts J, Liboiron A, McRuer D, Medill S, Parker S, Shury T, Smith M, Tschritter C, Wagner B, Poissant J....Sable Island, Nova Scotia, Canada hosts one of few natural populations of feral horses (Equus caballus) never exposed to anthelmintics. Coproculture revealed cyathostomes, Strongylus equinus, S. edentatus, and S. vulgaris, with S. equinus (unusually) dominating in adult horses and cyathostomes dominating in young horses (<3 years of age). We examined 35 horses found dead in the springs of 2017 and 2018, as well as fecal samples from live horses in spring (n = 45) and summer 2018 (n = 236) using McMaster fecal flotation and Baermann larval sedimentation on fresh samples, and modified Wiscon...
Tang L, Xiu Y, Yan L, Cui Y, Ma X, Ente M, Zhang Y, Li K, Zhang D.Reintroduction of endangered species to natural habitat is considered as an important tool for conservation. The effect of drug management on captive population of reintroduced species is largely neglected. Decreased drug efficacy could pose a substantial threat to health of animals. More importantly, captive population without proper drug administration could act as transmission medium of resistance nematodes to wild population, making it important to delay the occurrence of drug resistance in captive population. Ivermectin have been used in captive Przewalski's horse () to eradicate intestin...
The study evaluated the effectiveness of a commercially available polyherbal dewormer to control intestinal strongyles in naturally infected donkeys. The animals were allotted to two groups: treated with the herbal dewormer (n=8) according to manufacturer recommendations and untreated control group (n=6). Fecal samples were taken from each animal on days 0 (day of treatment), 14, 21 (day of second additional treatment), 35, and 42. Faecal egg count reduction tests showed very negligible or no reduction in number of strongyle eggs for donkeys in the phytotherapeutic treatment group compared to ...
Tydén E, Jansson A, Ringmark S.Horse grazing can be favorable from a biological diversity perspective. This study documented the occurrence of endo- and ectoparasites and sought to reduce parasite egg excretion with the anthelmintic drug pyrantel in 12 Gotlandsruss stallions maintained in a year-round grazing system for 2.5 years. Feces samples were collected monthly and all horses were treated with pyrantel, the anthelmintic drug of choice in biological diversity preservation, at study population mean cyathostomin eggs per gram (EPG) of >200. The relationship between cyathostomin EPG and body condition was studied, as was ...
Scare JA, Leathwick DM, Sauermann CW, Lyons ET, Steuer AE, Jones BA, Clark M, Nielsen MK.An alternative control regimen for drug-resistant parasites is combination deworming, where two drugs with different modes of action are administered simultaneously to target the same parasite. Few studies have investigated this in equine cyathostomins. We previously reported that an oxibendazole (OBZ) and pyrantel pamoate (PYR) combination was not sustainable against a cyathostomin population with high levels of OBZ and PYR resistance. This study consisted of a field study and two computer simulations to evaluate the efficacy of a moxidectin-oxibendazole (MOX-OBZ) combination against the same...
Egbe-Nwiyi TN, Paul BT, Cornelius AC.This study aimed to investigate the prevalence and intensity of nematode infection among slaughtered donkeys in Kaltungo, Nigeria. Methods: A total of 72 fecal samples were examined by salt flotation and the modified McMaster fecal egg count technique to morphologically identify nematodes eggs and determine their egg per gram (EPG) outputs. Results: Out of a total of 72 (100%) donkeys sampled, 36 (50%) tested positive, but the prevalence of nematodes was independent of the age, sex, and breed of donkeys (p>0.05). Among the four species of nematodes identified in single and mixed infections,...
Slusarewicz M, Slusarewicz P, Nielsen MK.Fecal egg counts are the primary diagnostic tools of equine parasitology and use of the McMaster test and its variants in clinical practice is widely recommended. Manual counting is, however, prone to various sources of human error. For example, in real-world situations analysts can be under significant pressure to process high numbers of samples in a limited time. This practice could affect test result quality, but yet no studies have determined whether this is the case. This study's purpose was to assess the effect of shortened counting duration (from either restricting counting time or coun...
Forteau L, Dumont B, Sallé G, Bigot G, Fleurance G.Strongyle infection is an important issue in horse breeding. It impairs horse health and performance, with young horses being the most sensitive. Strongyle control has long relied on the systematic use of chemical treatments. However, expanding anthelmintic resistance among strongyles calls for alternative options. Mixed grazing is assumed to reduce strongyle load on the pasture as the result of a dilution effect. This has been shown in small ruminants grazing with cattle, but the putative benefits of co-grazing between horses and cattle have not yet been evaluated. Here, we conducted field su...
Imani-Baran A, Abdollahi J, Akbari H, Jafarirad S, Moharramnejad S.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. Objective: 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. Methods: Thirty donkeys, naturally and severely infected with Stro...
Norris JK, Slusarewicz P, Nielsen MK.The efficacy of anthelmintic treatments against populations of endoparasites infecting livestock throughout the world is decreasing. To mitigate this, the use of fecal egg counts is recommended to determine both the necessity, and to ensure the appropriate choice, of anthelmintic treatment. Traditionally, and in order to facilitate easier identification and/or enumeration, samples are analysed after separating eggs from other fecal particulates by exposing them to a solution with a density higher than that of the eggs, but lower than the remaining fecal contents. While many parasite egg flotat...
Tzelos T, Morgan ER, Easton S, Hodgkinson JE, Matthews JB.Interval treatment control programmes used widely in equine helminth control have favoured the development of anthelmintic resistance worldwide. Best practice guidelines have been designed to address resistance and include the requirement for improved pasture hygiene to break helminth transmission cycles, along with anthelmintic application informed by the results of diagnostic tests to reduce selection pressure for resistance. Using an online questionnaire, this study examined uptake of measures recommended in these guidelines by UK horse owners. The survey comprised 58 questions spanning gra...
Abbas G, Ghafar A, Hurley J, Bauquier J, Beasley A, Wilkes EJA, Jacobson C, El-Hage C, Cudmore L, Carrigan P, Tennent-Brown B, Gauci CG, Nielsen MK....Cyathostomins are the most important and common parasitic nematodes of horses, with > 50 species known to occur worldwide. The frequent and indiscriminate use of anthelmintics has resulted in the development of anthelmintic resistance (AR) in horse nematodes. In this study we assessed the efficacy of commonly used anthelmintics against cyathostomins in Australian thoroughbred horses. Methods: Two drug efficacy trials per farm were conducted on two thoroughbred horse farms in the state of Victoria, Australia. In the first trial, the horses on Farm A were treated with single and combinations ...
Xiao L, Herd RP, Majewski GA.Efficacies of moxidectin and ivermectin were compared in four groups of eight ponies with natural parasite infections: placebo (Control), oral moxidectin gel at 0.3 mg kg-1 of body weight (Mox 0.3), oral moxidectin gel at 0.4 mg kg-1 of body weight (Mox 0.4), and oral ivermectin paste at 0.2 mg kg-1 of body weight (Ivermectin). Fecal samples were taken 0 and 2 weeks after treatment. Animals were necropsied and worms were collected 2 weeks after treatment. Moxidectin and ivermectin showed similar efficacy (99%) against adult cyathostomes, Strongylus spp., Triodontophorus spp. and Habronema musc...
Sargison N, Chambers A, Chaudhry U, Costa Júnior L, Doyle SR, Ehimiyein A, Evans M, Jennings A, Kelly R, Sargison F, Sinclair M, Zahid O.Understanding the composition of gastrointestinal nematode communities may help to mitigate or exploit parasite adaptations within their host. We have used nemabiome deep amplicon sequencing of internal transcribed spacer-2 (ITS-2) ribosomal DNA to describe the temporal and host species composition of gastrointestinal nematode communities following sampling of six Scottish ponies across 57 months. In the absence of parasite control, each horse showed seasonal trends of increases and decreases in faecal egg counts, consistent with the epidemiology of equine strongylid parasites, however, the c...
van Doorn DC, Ploeger HW, Eysker M, Geurden T, Wagenaar JA, Kooyman FN.The normal time interval between treatment of horses with a macrocyclic lactone (ML) and reappearance of strongyle eggs in the feces, or 'Egg Reappearance Period (ERP)', is at its shortest 8 weeks for ivermectin (IVM) and 12 weeks for moxidectin (MOX). Nowadays, it is not uncommon to find shorter ERPs, potentially indicating the beginning of the development of drug resistance. Whether all cyathostomin species contribute equally to a shortened ERP is not known. In the present study a Reverse Line Blot (RLB) on individual infective larvae was used to compare species composition before and after ...
Nielsen MK, Pfister K, von Samson-Himmelstjerna G.Since the 1960s equine parasite control has relied heavily on frequent anthelmintic treatments often applied with frequent intervals year-round. However, increasing levels of anthelmintic resistance in cyathostomins and Parascaris equorum are now forcing the equine industry to change to a more surveillance-based treatment approach to facilitate a reduction in treatment intensity. The principle of selective therapy has been implemented with success in small ruminant parasite control, and has also found use in horse populations. Typically, egg counts are performed from all individuals in the pop...
Traversa D, Milillo P, Barnes H, von Samson-Himmelstjerna G, Schurmann S, Demeler J, Otranto D, Lia RP, Perrucci S, Frangipane di Regalbono A....A broad scale study was carried out in 2008 to evaluate the distribution and species-specific occurrence of cyathostomin populations in horse yards from Europe. In total 102 properties and 3123 horses were included in Italy (60 yards and 1646 animals), United Kingdom (22 yards and 737 animals) and Germany (20 yards and 740 animals). Individual faecal samples were examined with a McMaster technique while pooled samples were subjected to the microscopic examination of in vitro cultured larvae and to a Reverse Line Blot (RLB) assay able to molecularly identify the most diffused 13 species of cyat...
Clayton HM.P. equorum is a common and ubiquitous parasite that persists for many years in stables and on pasture in spite of good hygiene and anthelmintic control programs. Foals are usually infected early in life. During the migratory phase of the infection, clinical signs include coughing and a nasal discharge followed by depression and unthriftiness as the worms mature in the gut. Some foals die as a result of intestinal impaction or rupture. Patency is established around 3 months of age, and fecal egg counts may rise to very high levels. From 6 months of age onwards, the ascarid burden diminishes as ...
Kuzmina TA, Kharchenko VO.In 2004-2006, 322 brood horses from 11 horse farms were examined using the faecal egg count reduction test (FECRT) to determine the presence and distribution of anthelmintic resistance in strongylids in Ukraine. The anthelmintic drugs "Albendazole-7.5" (7.5mg of albenazole, Ukraine) at a dose of 5mg per kg body weight and "Univerm" (0.2% aversectin C, Russia) at a dose of 0.5mg per kg body weight were used. Seventy-one horses from six farms were examined in vivo to investigate the influence of anthelmintic treatment on the gastrointestinal strongylid community structure. Horses were treated wi...
Schneider S, Pfister K, Becher AM, Scheuerle MC.As a consequence of the increasing levels of anthelmintic resistance in cyathostomes, new strategies for equine parasite control are being implemented. To assess the potential risks of these, the occurrence of strongyles was evaluated in a group of 1887 horses. The distribution of fecal egg counts (FECs), the frequency of anthelmintic drug use, and the deworming intervals were also analyzed. Between June 2012 and May 2013, 1887 fecal samples from either selectively or strategically dewormed horses were collected at 195 horse farms all over Germany and analyzed quantitatively with a modified Mc...
Stratford CH, Lester HE, Morgan ER, Pickles KJ, Relf V, McGorum BC, Matthews JB.Anthelmintic resistance in equine gastrointestinal nematodes is a threat to equine health and welfare. Detailed knowledge of anthelmintic use and parasite control methods is a prerequisite to identification of potential risk factors for resistance. Objective: To identify parasite control practices employed by equine owners in Scotland and investigate management factors associated with anthelmintic resistance. Methods: Questionnaire study of equine parasite control in Scotland. Methods: Questionnaires were available electronically, distributed at a conference and mailed to clients. Key areas ex...
Sallé G, Cortet J, Bois I, Dubès C, Guyot-Sionest Q, Larrieu C, Landrin V, Majorel G, Wittreck S, Woringer E, Couroucé A, Guillot J, Jacquiet P....Intestinal strongyles are the most problematic endoparasites of equids as a result of their wide distribution and the spread of resistant isolates throughout the world. While abundant literature can be found on the extent of anthelmintic resistance across continents, empirical knowledge about associated risk factors is missing. This study brought together results from anthelmintic efficacy testing and risk factor analysis to provide evidence-based guidelines in the field. It involved 688 horses from 39 French horse farms and riding schools to both estimate Faecal Egg Count Reduction (FECR) aft...
Traversa D, Klei TR, Iorio R, Paoletti B, Lia RP, Otranto D, Sparagano OA, Giangaspero A.In the present survey, 276 horses bred on 16 farms located in central and southern Italy were investigated for the presence of drug resistant cyathostomes by a Fecal Egg Count Reduction Test (FECRT). Sixteen to 20 animals were selected on each farm and randomly assigned to one of four equally sized treatment groups. Groups were treated with fenbendazole, pyrantel pamoate, ivermectin or moxidectin. Resistance to fenbendazole was declared on six farms (37.5%) and suspected in two farms (12.5%), with FECR values ranging from 41% to 88.3%. Resistance to pyrantel was found in two farms (12.5%) and ...
Herd RP.Seasonal rises in mean faecal egg output were observed in grazing ponies in spring (578 eggs per gram) and in summer (930 epg) on 30 April and 2 September, respectively, in untreated ponies. Pasture infectivity reached a peak of 18,486 third stage larvae (L3)/kg on 17 September, two weeks after peak egg counts, coincidental with abundant September rainfall (103.0 mm). Differentiation of infective larvae from pasture showed the cyathostomes (small strongyles) to be predominant, but Trichostrongylus axei assumed major importance from late August to October. The large strongyles were rarely detec...
Wirtherle N, Schnieder T, von Samson-Himmelstjerna G.Faecal egg counts (FECs) were made on samples from 1383 horses on 64 farms in northern Germany between August 2000 and November 2001. There were significant differences between the mean FECs in the two years; in 2000, 59.6 per cent of 369 samples were positive and in 2001, 32.6 per cent of 1014 samples were positive for strongyle eggs. The results of a FEC reduction test indicated that resistance to fenbendazole was present on all 10 farms where it had been used, including in 33 of 60 horses tested. In contrast, treatment with ivermectin resulted in the complete elimination of nematode eggs in...
Francisco I, Arias M, Cortiñas FJ, Francisco R, Mochales E, Dacal V, Suárez JL, Uriarte J, Morrondo P, Sánchez-Andrade R, Díez-Baños P....A coprological survey to determine the influence of some intrinsic factors (breed, age, and sex) on the infection by helminth parasites in equine livestock (n = 418) under an oceanic climate area (NW Spain) was conducted. Faecal samples were individually collected and analyzed by the coprological techniques. The main strongylid genera identified were Trichonema and Cyalocephalus spp (small strongyles) and Strongylus and Triodontophorus (large strongyles). The prevalence of gastrointestinal nematode was 89% (95% CI 86, 92) and 1% cestoda (0, 2). The percentage of horses with strongyloid parasit...
Lloyd S, Smith J, Connan RM, Hatcher MA, Hedges TR, Humphrey DJ, Jones AC.One hundred and fifty horse owners, primarily private owners and riding schools, replied to a questionnaire concerning the practices they used to control parasites. Twenty-seven had experienced a parasite problem. Faecal samples from 188 horses selected at random showed that worm control practices were generally successful; however, many owners were not following recommendations for slowing the development of resistant parasites. In 1996, 86 per cent of the owners were using either three or two classes of anthelmintic a year, and they used a median of six doses with a range from one to 11. App...
Kehrli D, Jandova V, Fey K, Jahn P, Gerber V.Multiple hypersensitivities (MHS) have been described in humans, cats, and dogs, but not horses. Objective: Horses suffering from recurrent airway obstruction (RAO), insect bite hypersensitivity (IBH), or urticaria (URT) will have an increased risk of also being affected by another one of these hypersensitivities. This predisposition for MHS also will be associated with decreased shedding of strongylid eggs in feces and with a single nucleotide polymorphism (SNP BIEC2-224511), previously shown to be associated with RAO. Methods: The first population (P1) included 119 randomly sampled horses re...
Ionita M, Howe DK, Lyons ET, Tolliver SC, Kaplan RM, Mitrea IL, Yeargan M.A sensitive and specific PCR hybridization assay was applied for species-specific monitoring of the small strongyle (Strongylida: Cyathostominae) populations in horses in a herd before and after treatment with the anthelmintic drug ivermectin. Fecal samples were collected pre- and post-treatment weekly from eight individual horses (four foals and four yearlings) for 6 weeks to determine counts of strongyle eggs per gram of feces (EPGs). Additionally, one foal and one yearling were nontreated controls. Also, one horse, from another herd known to be infected with Strongylus spp., was a positive ...
Hautala K, Näreaho A, Kauppinen O, Nielsen MK, Sukura A, Rajala-Schultz PJ.Gastrointestinal parasites, Parascaris sp. and strongyles, are common in young horses worldwide and control of these parasites is challenged by increasing anthelmintic resistance. Our aim was to identify risk factors for these infections as well as to assess the efficacy of fenbendazole (dose 7.5 mg/kg) and pyrantel embonate (dose 19 mg/kg) against Parascaris sp. We also evaluated association between owner observed symptoms and patent infections with these parasites. Fecal samples were collected from 367 young horses in Finland and a questionnaire study was conducted. Fecal egg counts were...
Fritzen B, Rohn K, Schnieder T, von Samson-Himmelstjerna G.Increasing prevalence of anthelmintic resistance in equine nematodes calls for a reexamination of current parasite control programmes to identify factors influencing control efficacy and development of resistance. Objective: To investigate if associations occur between prevalence of parasitic nematodes and management practices. Methods: German horse farms (n = 76) were investigated in 2003 and 2004. Information on farm and pasture management with respect to endoparasite control measures obtained using a questionnaire survey. Faecal examinations were performed in parallel. Results: Horses (n = ...
Denwood MJ, Reid SW, Love S, Nielsen MK, Matthews L, McKendrick IJ, Innocent GT.The Faecal Egg Count Reduction Test (FECRT) is the most widely used method of assessing the efficacy of anthelmintics, and is the only in vivo technique currently approved for use with horses. Equine Faecal Egg Count (FEC) data are frequently characterised by a low mean, high variability, small sample size and frequent zero count observations. Accurate analysis of the data therefore depends on the use of an appropriate statistical technique. Analyses of simulated FECRT data by methods based on calculation of the empirical mean and variance, non-parametric bootstrapping, and Markov chain Monte ...
Nielsen MK.Anoplocephalid tapeworms are commonly occurring in grazing horses around the world. Two currently available anthelmintics have documented high efficacy against Anoplocephala perfoliata; praziquantel in various dosages ranging from 1.0 to 2.5 mg/kg and pyrantel pamoate administered at 13.2 mg base/kg. Anthelmintic resistance has not been reported in A. perfoliata, but anecdotal reports made during 2022 have suggested a possible loss of efficacy for both actives. This paper reports fecal egg count data from a Thoroughbred operation in Central Kentucky in 2023. Fifty-six yearlings were first de...
Hernández JÁ, Arroyo FL, Suárez J, Cazapal-Monteiro CF, Romasanta Á, López-Arellano ME, Pedreira J, de Carvalho LMM, Sánchez-Andrade R....The usefulness of pellets industrially manufactured with spores of parasiticide fungi as a contribution to integrated nematode control was assessed in grazing horses throughout sixteen months. Two groups of 7 Pura Raza Galega autochthonous horses (G-T and G-P) were dewormed pour-on (1mg Ivermectin/kg bw) at the beginning of the trial, and other group (G-C) remained untreated. The G-P was provided daily with commercial pellets to which was added a mixture of fungal spores during the industrial manufacturing (2×10 spores of Mucor circinelloides and same dose of Duddingtonia flagrans/kg), and G-...
Uhlinger C.Four privately owned herds (25 to 49 animals per herd) were used in a five-year trial designed to evaluate the effect of anthelmintic schedules on the incidence of colic. These herds had been treated bi-monthly with non-ivermectin, non-benzimidazole drugs for two years before the trial. Prior parasitological studies showed that they had substantial pre-treatment faecal egg counts (900 to 2200 eggs per gramme), and that they were infected with benzimidazole-resistant cyathostomes. In Years 1 and 2 of the trial, all herds (A, B, C, D) were treated bi-monthly with non-ivermectin anthelmintics (Sc...
Dauparaitė E, Kupčinskas T, von Samson-Himmelstjerna G, Petkevičius S.With intensive use of anthelmintic drugs in recent decades, anthelmintic resistance (AR) in horse nematodes is becoming a growing issue in many countries. However, there is little available information about the parasites, treatment practices or AR in the horse population in Lithuania. The aim of this study was to assess the current situation of AR on horse farms in Lithuania. The study was conducted in 25 stables on horses with a strongyle faecal egg count (FEC) of ≥ 200 eggs per gram. A faecal egg count reduction test (FECRT) was performed on each farm after administration of ivermectin ...
Nápravníková J, Petrtýl M, Stupka R, Vadlejch J.The detection and quantification of nematode eggs using fecal egg count techniques have an irreplaceable role in equine parasitic control. The reliability, particularly precision and accuracy, of individual techniques have been described only for strongylid infections. The aim of this study was to compare three fecal egg count techniques used for the detection of the two most common equine nematode infections: strongylid and ascarid. The Simple McMaster, Concentration McMaster and Mini-FLOTAC techniques were tested on spiked fecal samples with various levels of egg concentration (50, 100, 200,...
Stratford CH, Lester HE, Pickles KJ, McGorum BC, Matthews JB.Cyathostomins comprise 50 helminth species, considered the most problematic equine endoparasites. Three classes of anthelmintic are currently licensed for their control, namely the benzimidazoles (fenbendazole), tetrahydropyrimidines (pyrantel) and macrocyclic lactones (ivermectin and moxidectin). Anthelmintic resistance in cyathostomins is common. With no new classes expected in the near future, it is essential to determine the efficacy of the available anthelmintics to inform future control programmes. Objective: To determine the efficacy of all 3 anthelmintic classes against strongyles in e...
Tzelos T, Morgan ER, Easton S, Hodgkinson JE, Matthews JB.Interval treatment control programmes used widely in equine helminth control have favoured the development of anthelmintic resistance worldwide. Best practice guidelines have been designed to address resistance and include the requirement for improved pasture hygiene to break helminth transmission cycles, along with anthelmintic application informed by the results of diagnostic tests to reduce selection pressure for resistance. Using an online questionnaire, this study examined uptake of measures recommended in these guidelines by UK horse owners. The survey comprised 58 questions spanning gra...
Nielsen MK, Gee EK, Hansen A, Waghorn T, Bell J, Leathwick DM.Strongylid and ascarid parasites are omnipresent in equine stud farms, and ever-increasing levels of anthelmintic resistance are challenging the industry with finding more sustainable and yet effective parasite control programs. Objective: To evaluate egg count levels, bodyweight and equine health under defined parasite control protocols in foals and mares at two Standardbred and two Thoroughbred stud farms. Methods: Longitudinal randomised field trial. Methods: A total of 93 foals were enrolled and split into two treatment groups, and 99 mares were enrolled and assigned to three treatment gro...
