Nematodes are parasitic worms that can infect horses, affecting their health and well-being. These parasites typically inhabit the gastrointestinal tract of equines, where they can cause a variety of health issues. Common nematodes affecting horses include strongyles, ascarids, and pinworms. The presence and load of nematodes in horses can lead to symptoms such as weight loss, colic, and diarrhea, and can impact overall performance and health. Monitoring and managing nematode infections is an important aspect of equine veterinary care. This page compiles peer-reviewed research studies and scholarly articles that explore the biology, epidemiology, and management strategies of nematode infections in horses.
Żak-Bochenek A, Bajzert J, Sambor D, Siwińska N, Szponar B, Łaczmański Ł, Żebrowska P, Czajkowska A, Karczewski M, Chełmońska-Soyta A.The defensive function of the intestinal mucosa depends both on the ability to secrete immunoglobulin A and communication with the mucus microbiome. In horses, the functioning of this system is also influenced by the presence of nematode eggs. Feces collected from healthy horses were examined to determine the fecal egg count, immunoglobulin A level (ELISA), microbiome composition (Next-Generation Sequencing, NGS, V3−V4 and V7−V9 hypervariable regions of the 16S rRNA gene analysis and short-chain fatty acid (SCFA) production ((high-performance liquid chromatography, HPLC). In the taxonomic ...
Cain JL, Norris JK, Ripley NE, Suri P, Finnerty CA, Gravatte HS, Nielsen MK.Parasitic nematodes, including large roundworms colloquially known as ascarids, affect the health and well-being of livestock animals worldwide. The equine ascarids, Parascaris spp., are important parasites of juvenile horses and the first ascarids to develop widespread anthelmintic resistance. The microbiota has been shown to be an important factor in the fitness of many organisms, including parasitic nematodes, where endosymbiotic Wolbachia have been exploited for treatment of filariasis in humans. Methods: This study used short-read 16S rRNA sequences and Illumina sequencing to characterize...
Nielsen MK.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 docume...
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...
Dauparaitė E, Kupčinskas T, Varady M, Petkevičius S.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 (F...
Abo-Aziza FAM, Hendawy SHM, Abdullah HHAM, El Namaky A, Laidoudi Y, Mediannikov O.Equine filariosis (EF) is a neglected vector-borne disease caused by nematode species belonging to the Onchocercidae and Setariidae families. Aside from their zoonotic potential, some species are responsible for serious health problems in equids worldwide, leading to significant economic difficulties. Here, we molecularly investigated equine blood samples (320 horses and 109 donkeys from Egypt) and four adult worms isolated from the peritoneal cavity of 5 out of the 94 slaughtered donkeys. In addition, quantitative enzyme-linked immunoassays (ELISAs) targeting circulating cytokines were used t...
Cain JL, Nielsen MK.The equine ascarids, Parascaris spp., are important nematode parasites of juvenile horses and were historically model organisms in the field of cell biology, leading to many important discoveries, and are used for the study of chromatin diminution. In veterinary parasitology, Parascaris spp. are important not only because they can cause clinical disease in young horses but also because they are the only ascarid parasites to have developed widespread anthelmintic resistance. Despite this, much of the general biology and mechanisms of anthelmintic resistance are poorly understood. This review co...
Chicca J, Cazeault NR, Rus F, Abraham A, Garceau C, Li H, Atwa SM, Flanagan K, Soto ER, Morrison MS, Gazzola D, Hu Y, Liu DR, Nielsen MK, Urban JF....Bacillus thuringiensis (Bt) is a Gram-positive soil bacterium that is widely and safely applied in the environment as an insecticide for combatting insect pests that damage crops or are disease vectors. Dominant active ingredients made by Bt are insect-killing crystal (Cry) proteins released as crystalline inclusions upon bacterial sporulation. Some Bt Cry proteins, e.g., Cry5B (formally Cry5Ba1), target nematodes (roundworms) and show exceptional promise as anthelmintics (cures for parasitic nematode diseases). We have recently described inactivated bacteria with cytosolic crystal(s) (IBaCC) ...
Han L, Lan T, Lu Y, Zhou M, Li H, Lu H, Wang Q, Li X, Du S, Guan C, Zhang Y, Sahu SK, Qian P, Zhang S, Zhou H, Guo W, Chai H, Wang S, Liu Q, Liu H....The evolution of parasites is often directly affected by the host's environment. Studies on the evolution of the same parasites in different hosts are of great interest and are highly relevant to our understanding of divergence. Methods: Here we performed whole-genome sequencing of Parascaris univalens from different Equus hosts (horses, zebras and donkeys). Phylogenetic and selection analyses were performed to study the divergence and adaptability of P. univalens. Results: At the genetic level, multiple lines of evidence indicate that P. univalens is mainly separated into two clades (horse-de...
Baranova MV, Panova OA, Polukhina DN, Panova DS.Anthelmintics are used to control equine nematodes. However, helminth resistance to regularly used drugs is a well-known challenge. Among tests to assess effective control and monitor resistance, the most common is the fecal egg count reduction test (FECRT). In the absence of reliable FECRT results, the nematode egg reappearance period (ERP) is taken into account. This study aimed to examine horses from farms around the Moscow Region to assess nematode resistance through ERP after therapy. Unassigned: In the first stage, fecal samples from 280 horses were examined by the flotation method with ...
Jürgenschellert L, Krücken J, Bousquet E, Bartz J, Heyer N, Nielsen MK, von Samson-Himmelstjerna G.The infection of horses with strongylid nematodes is highly prevalent, with multi-species infections being the rule. spp. and in particular are amongst the most pathogenic strongyle equine parasites. Presumably due to regular strategic anthelmintic treatments in combination with long prepatencies, prevalence of these worms was severely reduced in past decades. In this study, 484 horses from 48 farms in Berlin/Brandenburg, Germany were sampled between May 2017 and January 2018. Mini-FLOTAC and combined sedimentation/flotation were used to analyse faecal samples and larval cultures were carrie...
Mathewos M, Teshome D, Fesseha H.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 9...
Dube F, Hinas A, Roy S, Martin F, Åbrink M, Svärd S, Tydén E.The nematode Parascaris univalens is one of the most prevalent parasitic pathogens infecting horses but anthelmintic resistance undermines treatment approaches. The molecular mechanisms underlying drug activity and resistance remain poorly understood in this parasite since experimental in vitro models are lacking. The aim of this study was to evaluate the use of Caenorhabditis elegans as a model for P. univalens drug metabolism/resistance studies by a comparative gene expression approach after in vitro exposure to the anthelmintic drug ivermectin (IVM). Methods: Twelve adult P. univalens worms...
Özben M, von Samson-Himmelstjerna G, Freiin von Streit MKB, Wilkes EJA, Hughes KJ, Krücken J.Benzimidazoles resistance is widespread in strongyle parasitic nematodes and associated with polym orphisms in the codons 167, 198 and 200 of isotype 1 β-tubulin (tbb-1). In ascarids, benzimidazole (BZ) resistance has rarely been reported and in none of these cases were any of these polymorphisms detected. Here, available genome and transcriptome data from WormBase ParaSite were used to compare the complete β-tubulin reservoirs of , and . Adult spp. specimens collected in Australia from horses after BZ treatment (susceptible, n = 13) or surviving BZ treatment and collected after ivermectin...
Mansell SE, Behnke MC.The nematode Onchocerca cervicalis is the most common causative agent of equine onchocerciasis; this condition is characterised by pruritus and dermatitis and is a differential diagnosis for insect bite hypersensitivity. Onchocerciasis is currently presumed of minor importance within the UK, however prevalence may increase if macrocyclic lactone use declines amid concerns about anthelmintic resistance in gastrointestinal nematodes. This survey aimed to establish O. cervicalis awareness and knowledge levels amongst UK equine veterinarians and to determine approximate numbers of UK horses affect...
Halvarsson P, Gustafsson K, Höglund J.A questionnaire was sent to sheep owners in Sweden to get information about anthelmintic drug use. The survey also investigated how respondents experienced problems with gastrointestinal nematode infections (GIN) focusing on Haemonchus contortus. The response rate was 31% and included both conventional and organic farms. The use of anthelmintics was low (45%), among which a majority (76%) drenched ewes on a single occasion, mostly with ivermectin (59%) followed by albendazole (19%). Other drugs were used rarely, however, unawareness of GIN risk was high (19%), especially among respondents with...
Nielsen MK, von Samson-Himmelstjerna G, Kuzmina TA, van Doorn DCK, Meana A, Rehbein S, Elliott T, Reinemeyer CR.This guideline have been developed to assist in the design, execution, and interpretation of studies to assess the efficacy of anthelmintic drugs against internal parasites of equines, including nematodes, cestodes, and larval instars of Gasterophilus spp. The design and execution of critical and controlled studies are outlined, and their advantages and disadvantages are discussed. Unique considerations for specific target parasites are included. Information is also provided on selection of animals, procedures for randomization, housing, feeding, dosage titration, dosage confirmation and field...
Lauková A, Micenková L, Kubašová I, Bino E, Kandričáková A, Plachá I, Štrkolcová G, Gálik B, Kováčik A, Halo M, Simonová MP.The beneficial influence of bacteriocin-producing, probiotic, mostly non-autochthonous bacteria has already been reported in various animals. However, their use in horses provides limited information, and results with autochthonous bacteria have not been reported. Therefore, the main objective of this model study was to test the effect of autochthonous, bacteriocin-producing faecal strain Enterococcus faecium EF 412 application in horses. One gram of freeze-dried EF 412 strain (10 CFU/mL for 21 days) was applied to horses in a small feed ball. Clinically healthy horses (12), Slovak warm-blood ...
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 ...
Živković S, Pavlović I, Mijatović B, Trailović I, Trailović D.This study aimed to investigate the prevalence, intensity and risk factors (age and gender) promoting the intestinal helminthic infections of the Domestic mountain ponies and Balkan donkeys in Serbia. Methods: Prevalence, intensity and risk factors influencing helminth infection in horses (n=39) and donkeys (n=18) at the site of Nature Park Stara Planina, were studied from May to Sep 2015. The presence of one or several gastrointestinal helminth species was confirmed by faecal flotation in 97.43% of horses and 88.88% of donkeys included in the monitoring. The identified helminth species were ,...
Palozzo A, Traversa D, Marruchella G, Celani G, Morelli S, Petrizzi L.Cutaneous habronemosis in horses is caused by larvae of the spirurid nematodes Habronema microstoma and Habronema muscae. These lesions, also known as "summer sores'', are often severe and disfiguring. Although Habronema-caused lesions at the coronary grooves have been described, cases of hoof cracks with secondary summer sores have never been reported. The present case describes clinic-pathological and surgical features of a quarter crack case complicated by cutaneous habronemosis at the dermal layers. A 15-year-old, Andalusian stallion was referred to the Veterinary Teaching Hospital of the ...
Martin F, Eydal M, Höglund J, Tydén E.The equine roundworm Parascaris univalens has developed resistance to the three anthelmintic substances most commonly used in horses. The mechanisms responsible for resistance are believed to be multi-genic, and transport proteins such as the P-glycoprotein (Pgp) family have been suggested to be involved in resistance in several parasites including P. univlaens. To facilitate further research into the mechanisms behind drug metabolism and resistance development in P. univalens we aimed to develop an in vitro model based on larvae. We developed a fast and easy protocol for hatching P. univalens...
Trailovic SM, Rajkovic M, Marjanovic DS, Neveu C, Charvet CL. sp. is the only ascarid parasitic nematode in equids and one of the most threatening infectious organisms in horses. Only a limited number of compounds are available for treatment of horse helminthiasis, and sp. worms have developed resistance to the three major anthelmintic families. In order to overcome the appearance of resistance, there is an urgent need for new therapeutic strategies. The active ingredients of herbal essential oils are potentially effective antiparasitic drugs. Carvacrol is one of the principal chemicals of essential oil from , , , , and herbs. However, the antiparasi...
Fausto GC, Fausto MC, Vieira ÍS, Freitas SG, Carvalho LM, Oliveira IC, Silva EN, Campos AK, Araújo JV.Equine gastrointestinal nematodiosis contributes to the lower productivity of these animals. There are growing reports of the emergence of nematodes resistant to the drugs used for decades in anthelmintic treatments. An alternative to the emergence of resistance may be the use of nematophagous fungi as a complementary method of treatment. Therefore, the objective was to evaluate the effects of the use of the product Bioverm® as a carrier of Duddingtonia flagrans, on pasture contamination level and equine parasitic burden. Sixteen mares were used, divided into two groups, one control and one t...
Urban JF, Nielsen MK, Gazzola D, Xie Y, Beshah E, Hu Y, Li H, Rus F, Flanagan K, Draper A, Vakalapudi S, Li RW, Ostroff GR, Aroian RV. and are important parasites in the family Ascarididae, large, ubiquitous intestinal-dwelling nematodes infecting all classes of vertebrates. Parasitic nematode drug resistance in veterinary medicine and drug recalcitrance in human medicine are increasing worldwide, with few if any new therapeutic classes on the horizon. Some of these parasites are zoonotic, , is passed from humans to pigs and . The development of new therapies against this family of parasites would have major implications for both human and livestock health. Here we tested the therapeutic ability of a paraprobiotic or dead ...
Zanet S, Battisti E, Labate F, Oberto F, Ferroglio E.Nematodes are an important cause of disease and loss of performance in horses. Changes in the parasitic fauna of horses have occurred in the past few decades, making cyathostomins the major parasites in adult horses, while large strongyles have become less prevalent. spp. remains the most important parasite infecting foals and weanlings. Anthelmintic resistance is highly prevalent in cyathostomins and spp. worldwide and it must be factored into treatment decisions. To assess anthelmintic efficacy in Northern Italy, we sampled 215 horses from 17 sport and horse-breeding farms. Fecal egg count...
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 ...
Paraschou G, Adako GM, Priestnall SL, Burden FA.Three donkeys were presented with progressive lameness and distal suspensory ligament breakdown in multiple limbs. Treatment with nonsteroidal anti-inflammatory drugs was only partially effective and eventually the donkeys were euthanized due to further progression of the lameness and concerns for their welfare. At necropsy, the distal part of the suspensory ligaments in multiple limbs, including the suspensory ligament branches, was markedly thickened, enlarged, and mottled white and brown on cut section. In one case, adult sp. nematodes were grossly identified embedded within the suspensory...
Salant H, Rojas A, Yardeny D, Brenner O, Schvartz G, Baneth G, Dvir E.Draschia megastoma, Habronema microstoma, and Habronema muscae are the etiological agents of cutaneous habronemosis, commonly known as summer sores, an inflammatory cutaneous and ocular parasitic disease of horses and other equids transmitted by flies. Here, we describe a cluster of cutaneous habronemosis in five horses that showed single or multiple typical cutaneous ulcerative wounds located on the face, lower forelegs or hindquarters in Israel with the presence of typical "sulphur granules." All affected animals were confirmed by histopathological and/or molecular methods to be infected by ...
Szewc M, De Waal T, Zintl A.Gastrointestinal nematodes (GIN) are a cause of significant losses in animal production worldwide. In recent years, there have been important advances in the biological control of GIN of ruminants and horses. While these measures are still relatively under-utilised in practice, interest will undoubtedly grow due to the emergence of drug resistant parasite populations, the rise in demand for organically farmed products (which does not allow prophylactic use of drugs, including anthelmintics) and legislation, which regulates and restricts the use of anthelmintics. This review provides an overvie...
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-...
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 ...
Gao Y, Zhang Y, Yang X, Qiu JH, Duan H, Xu WW, Chang QC, Wang CR.Equine strongyles, the significant nematode pathogens of horses, are characterized by high quantities and species abundance, but classification of this group of parasitic nematodes is debated. Mitochondrial (mt) genome DNA data are often used to address classification controversies. Thus, the objectives of this study were to determine the complete mt genomes of three Cyathostominae nematode species (, and ) of horses and reconstruct the phylogenetic relationship of Strongylidae with other nematodes in Strongyloidea to test the hypothesis that spp. belong to Cyathostominae using the mt genomes...
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,...
Lindgren K, Ljungvall O, Nilsson O, Ljungström BL, Lindahl C, Höglund J.Environmental contamination and the egg excretion pattern of the ascarid Parascaris equorum (Nematoda) was investigated in relation to anthelmintic treatment on a Swedish stud farm. Faecal samples from 15 foals, dewormed every 8th-week with a paste formulation of ivermectin at the standard dose rate of 0.2 mg/kg bodyweight, were collected at five sampling occasions between August and November 2006. In addition, soil samples were obtained from four paddocks used by these foals in November 2006. The number of eggs per gram (epg) was counted in both faeces and soil. Egg excretion started when the...
Solismaa M, Laaksonen S, Nylund M, Pitkänen E, Airakorpi R, Oksanen A.In autumn 2006, Finnish meat inspection data revealed lesions in tendons, muscles and ligaments of bovine hind legs leading to partial condemnation of carcasses. In gross pathological examination at Finnish Food Safety Authority Evira, Oulu (now Fish and Wildlife Health) Research Unit, Onchocerca sp. (Filarioidea; Onchocercidae) nematodes were detected in lesions. Due to this, a pilot study was made in order to find out what filarioid nematodes do occur in cattle, horses and sheep in Finland. Methods: Ventral skin biopsies from 209 dairy cattle and 42 horses, as well as blood samples from 209 ...
Klei TR, Chapman MR.Defining the characteristics of immunity and immune responses to equine cyathostome infections is clearly important to advancing our understanding of the development of these nematodes within the host, the clinical conditions attributed to them, and in developing more rational and novel strategies for their control. Nonetheless, little is currently known on this topic. Current data based on field observations, worm burdens and fecal egg counts suggest that horses acquire a resistance to cyathostome infection with age. This response is slow to develop and incomplete in that most horses regardle...
Wright JD, Kelly WR, Waddell AH, Hamilton J.Verminous encephalomyelitis due to Angiostrongylus cantonensis larvae was diagnosed in 2 foals at necropsy. The principal clinical feature was tetraparesis, although history and neurological examination revealed progressive and multifocal neurological disease. At presentation, a tentative diagnosis of parasitic larval migration involving the central nervous system (CNS), presumably due to Strongylus vulgaris, was proposed. Dissection of the spinal cord in one case resulted in recovery of intact larvae of both sexes of A. cantonensis. In both foals, histopathology of the brain and spinal cord r...
Duan H, Gao JF, Hou MR, Zhang Y, Liu ZX, Gao DZ, Guo DH, Yue DM, Su X, Fu X, Wang CR.The complete mitochondrial (mt) genome sequence of Triodontophorus brevicauda, an intestinal equine nematode parasite was determined for the first time. The circular T. brevicauda mt genome is 14,305 bp in length and contains 36 genes, of which 12 code for protein, 22 for transfer RNA, and two for ribosomal RNA, and lacks atp8 mtDNA gene. Phylogenetic analysis based on the concatenated amino acid sequence of the 12 protein-coding genes was performed using three different tree-building methods. The Strongyloidea cluster divides into two large branches, and each nematode family included in our s...
Ogbourne CP.Observations have been made on the development and survival of the free-living stages in faeces deposited out of doors at different times of year, and on the migration of infective larvae to the surrounding herbage. Laboratory experiments were performed to assist in the interpretation of the field observations. Studies were made on the rate of development to the infective stage in faeces kept at different temperatures. The rates at which eggs and larvae of Strongylus vulgaris, S edentatus, S. equinus and Trichonema nassatum developed on faecal-agar cultures at different temperatures were compa...
Urban JF, Nielsen MK, Gazzola D, Xie Y, Beshah E, Hu Y, Li H, Rus F, Flanagan K, Draper A, Vakalapudi S, Li RW, Ostroff GR, Aroian RV. and are important parasites in the family Ascarididae, large, ubiquitous intestinal-dwelling nematodes infecting all classes of vertebrates. Parasitic nematode drug resistance in veterinary medicine and drug recalcitrance in human medicine are increasing worldwide, with few if any new therapeutic classes on the horizon. Some of these parasites are zoonotic, , is passed from humans to pigs and . The development of new therapies against this family of parasites would have major implications for both human and livestock health. Here we tested the therapeutic ability of a paraprobiotic or dead ...
Dowdall SM, Proudman CJ, Klei TR, Mair T, Matthews JB.Cyathostomins are the most common parasitic nematodes of horses. Larval stages, which inhabit the intestinal wall, are particularly pathogenic and can cause severe colitis and colic. Despite their clinical importance, diagnostic techniques for the prepatent stages do not exist. A method that could estimate mucosal infection intensity would have a major impact on the control and diagnosis of cyathostominosis. Here, serum IgG(T) responses to two larval antigen complexes of 25 and 20 kDa were quantified in horses with experimental infections, natural infections and in horses that presented with c...
Vidyashankar AN, Kaplan RM, Chan S.Resistance to anthelmintics in gastrointestinal nematodes of livestock is a serious problem and appropriate methods are required to identify and quantify resistance. However, quantification and assessment of resistance depend on an accurate measure of treatment efficacy, and current methodologies fail to properly address the issue. The fecal egg count reduction test (FECRT) is the practical gold standard for measuring anthelmintic efficacy on farms, but these types of data are fraught with high variability that greatly impacts the accuracy of inference on efficacy. This paper develops a statis...
Akagami M, Shibahara T, Yoshiga T, Tanaka N, Yaguchi Y, Onuki T, Kondo T, Yamanaka T, Kubo M.A ten-year-old Shetland pony gelding showed low appetite, ataxia, peculiar swaying, clouding of consciousness, and ultimately died. At necropsy, multiple coalescing granulomatous foci were detected in the kidneys, and small necrotic lesions were found in the cerebellum. Histologic examination of the renal tissue sections revealed extensive granuloma, and Halicephalobus gingivalis-like nematodes were seen. Similar nematodes were found in the granulomatous or necrotic lesions of the renal lymph nodes and cerebellum, and were also frequently detected in cerebrospinal meningovascular lesions. Morp...
Hermosilla C, Coumbe KM, Habershon-Butcher J, Schöniger S.A fatal case of eosinophilic and granulomatous meningoencephalitis caused by the free-living panagrolaimid nematode Halicephalobus gingivalis is reported in a 10-year-old Welsh gelding in the United Kingdom. Clinical examination first revealed behavioural abnormalities which rapidly progressed to severe ataxia, reduced mentation status and cranial nerve signs. Despite symptomatic treatment no amelioration of neurological signs was achieved and the horse was subjected to euthanasia. A complete post mortem examination revealed eosinophilic and granulomatous meningoencephalitis mainly affecting t...
Silva AV, Costa HM, Santos HA, Carvalho RO.Thirty six horses from nine Brazilian states (Goiás, Minas Gerais, Pará, Maranhão, Piauí, Paraíba, Pernambuco, Rio Grande do Norte, and Ceará) were examined for infections by small strongyles. The following species were identified: Cylicocyclus nassatus, C. insigne, C. brevicapsulatus, C. leptostomum, C. radiatus, C. ultrajectinus, C. ashworthi, Cylicostephanus goldi, C. calicatus, C. minutus, C. longibursatus, Petrovinema poculatum, Coronocyclus coronatus, C. labiatus, C. labratus, Cyathostomum catinatum, C. pateratum, C. alveatum, Parapoteriostomum euproctus, Cylicodontophorus bicorona...
Studzińska MB, Tomczuk K, Demkowska-Kutrzepa M, Szczepaniak K.Postmortem parasitic examinations of the large intestines of 725 slaughtered horses from individual farmers in southeastern Poland were carried out. The examinations were carried out monthly since February 2006 until January 2007 (except for August 2007 because of a technological stoppage in the slaughterhouse). The examinations included the intensiveness and extensiveness of the infestation of the Strongylidae belonging to the Strongylus genus. The Strongylidae were found in 26.5% of the examined horses. Strongylus vulgaris was the most dominant nematode and had a 22.8% prevalence, Strongylus...
The Journal of parasitologyMay 23, 2003
Volume 89, Issue 2 309-314 doi: 10.1645/0022-3395(2003)089[0309:POSNIN]2.0.CO;2
Chapman MR, French DD, Klei TR.One hundred and seventeen ponies were surveyed for the seasonal prevalence of strongyloid parasites, particularly cyathostomes, and for host- and age-related differences in these infections. For 56 ponies, all stages of the cyathostome life cycle, both mucosal and luminal, were enumerated. Total numbers of cyathostomes and percentage of developing larvae (DL) encysted in the mucosa remained constant in all 4 seasons of the year, whereas a significant increase in the percentage of adults in the cyathostome population occurred in fall. In yearling ponies, encysted early third-stage larvae consti...
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 ...
Corbett CJ, Love S, Moore A, Burden FA, Matthews JB, Denwood MJ.The level of anthelmintic resistance within some cyathostomin parasite populations has increased to the level where sole reliance on anthelmintic-based control protocols is not possible. Management-based nematode control methods, including removal of faeces from pasture, are widely recommended for use in association with a reduction in anthelmintic use to reduce selection pressure for drug resistance; however, very little work has been performed to quantitatively assess the effectiveness of such methods. Methods: We analysed data obtained from 345 donkeys at The Donkey Sanctuary (Devon, UK), m...
Bredtmann CM, Krücken J, Murugaiyan J, Kuzmina T, von Samson-Himmelstjerna G.Human and animal health is globally affected by a variety of parasitic helminths. The impact of co-infections and development of anthelmintic resistance requires improved diagnostic tools, especially for parasitic nematodes e.g., to identify resistant species or attribute pathological effects to individual species or particular species combinations. In horses, co-infection with cyathostomins is rather a rule than an exception with typically 5 to 15 species (out of more than 40 described) per individual host. In cyathostomins, reliable morphological species differentiation is currently limited ...
Larsen M.Resistance against anthelmintics is widespread, particularly in parasitic nematode populations of small ruminants. Several new techniques or supplements have been developed or are under investigation. Biological control (BC) is one of these new methods. The net-trapping predacious fungus Duddingtonia flagrans produces thick walled resting spores, chlamydospores, which are able to survive passage through the gastrointestinal tract of cattle, horses, sheep and pigs. Under Danish climatic conditions it has been shown that the number of parasite larvae on pasture and the worm burden of the grazing...
Kuzmina TA, Lyons ET, Tolliver SC, Dzeverin II, Kharchenko VA.The aims of the study were to determine fecundity of several strongylid species parasitizing domestic horses and analyze possible relations between numbers of eggs in female uteri and size of both the eggs and the nematodes as well as the influence of fecundity on proportion of species in the strongylid community. Twenty-five specimens from each of 15 strongylid species (Strongylus vulgaris, Strongylus edentatus, Triodontophorus serratus, Triodontophorus brevicauda, Triodontophorus tenuicollis, Cyathostomum catinatum, Coronocyclus coronatus, Cylicocyclus nassatus, Cylicocyclus insigne, Cylicoc...
Braga FR, Araújo JV, Silva AR, Carvalho RO, Araujo JM, Ferreira SR, Carvalho GR.The predatory capacity of the nematophagous fungus Pochonia chlamydosporia (isolate VC4) embedded in sodium alginate pellets after passage through the gastrointestinal tract of horses was assessed in vitro against Oxyuris equi eggs. Twelve previously dewormed crossbred mares, average weight of 362.5kg (+/-21) were used in the experiment. Each animal of the treated group received an oral dose (100g) of sodium alginate pellets containing P. chlamydosporia mycelial mass. The control group received pellets without fungus. Faecal samples from fungus-treated and control groups were collected at inte...
Sevá ADP, Pena HFJ, Nava A, Sousa AO, Holsback L, Soares RM.Morro do Diabo State Park (MDSP) is a significant remnant of the Atlantic Rain Forest in Brazil and is surrounded by rural properties. In that area, wild and domestic animals and humans are in close contact, which facilitates the two-way flow of infectious diseases among them. We assessed endoparasites in domestic livestock from all rural properties surrounding MDSP. There were sampled 197 cattle, 37 horses, 11 sheep, 25 swine, 21 dogs, one cat and 62 groups of chickens from 10 large private properties and 75 rural settlements. Eimeria spp. was present in almost all hosts, excepted in horses, ...
Blackhall WJ, Kuzmina T, von Samson-Himmelstjerna G.Resistance to benzimidazoles (BZ) in the gastrointestinal nematodes of livestock is characterised by the presence of specific polymorphisms in the β-tubulin isotype 1 protein, a component of microtubules. The most prevalent polymorphism associated with resistance in nematodes infecting cattle, sheep, and goats is found at codon 200, with minor occurrences of polymorphisms at codons 167 and 198. In the cyathostomins that infect horses, however, a polymorphism at codon 167 appears to be more common than the codon 200 polymorphism. In the present study, a focussed analysis of PCR-amplified β-tu...
Al Anazi AD, Alyousif MS.This study aimed to provide recent data on the occurrence of non-strongyle intestinal parasite infestation in horses in the Riyadh region of Saudi Arabia as a basis for developing parasite control strategies. We conducted necropsy for 45 horses from September 2006 to November 2007 in the Riyadh region, Saudi Arabia. 39 out of 45 horses were infected with intestinal parasites with an infestation rate of 86.6%. Infestations with seven nematode species and two species of Gasterophilus larva were found. The most prevalent parasites were Strongyloides westeri (64.4%) and Parascaris equorum (28.8%) ...
Mathewos M, Teshome D, Fesseha H.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 9...
