Parasites are organisms that live on or within a host, deriving nutrients at the host's expense. In horses, parasitic infections can affect various systems, including the gastrointestinal tract, skin, and respiratory system. Common equine parasites include strongyles, ascarids, tapeworms, and bots. These parasites can lead to a range of health issues, from mild discomfort to severe disease, depending on the type and burden of the infestation. This page compiles peer-reviewed research studies and scholarly articles that explore the biology, life cycle, and impact of parasites on equine health, as well as strategies for diagnosis, treatment, and prevention of parasitic infections in horses.
Salas-Romero J, Gómez-Cabrera KA, Aguilera-Valle LA, Bertot JA, Salas JE, Arenal A, Nielsen MK.Increasing levels of anthelmintic resistance observed in equine cyathostomin parasites have led to recommendations of selective anthelmintic treatment strategies to lower the selection pressure favoring resistant populations. This principle is based on determining strongyle fecal egg counts from all herd members, and treating those exceeding a predetermined treatment cutoff. However, epidemiological information is lacking from horses kept under tropical conditions, where parasite burdens may be of a different composition and magnitude compared to those of horses kept under temperate climate co...
Castilla-Castaño E, Vischi A, Navarro C, Lecru LA, Ribeiro C, Pradier S, Cadiergues MC.Two open-controlled studies evaluated the tolerance and the efficacy of a 10 mg/mL deltamethrin-based pour-on solution (Deltanil®; Virbac, France) in treating (study 1) and preventing (study 2) natural Damalinia equi infestations in horses. In study 1, seven adult horses received 10 mL of the solution from mane to tail head on day 0 (D0). Four adult horses, living separately, served as non-treated controls. All were naturally infected. Lice burden was recorded by counting the number of live parasites, bilaterally, over seven anatomic regions. Lesional score was based on alopecia, crusts, papu...
Davitkov D, Davitkov D, Vucicevic M, Stanisic L, Radakovic M, Glavinic U, Stanimirovic Z.Equine piroplasmosis in donkeys has been recognised as a serious problem of major economic importance. The present molecular study is the first investigation of the presence of Theileria equi and Babesia caballi in Balkan donkeys and of the possible haematological alterations related to it. A total of 70 apparently healthy donkeys from Serbia were included in this study. The overall prevalence of T. equi infection in donkeys tested with multiplex PCR was 50%. There was no B. caballi-positive sample. Infections in donkeys included in this study seem to be associated with decreased red blood cel...
Alanazi AD, Mukbel RM, Alyousif MS, AlShehri ZS, Alanazi IO, Al-Mohammed HI.In the last decade, Parascaris spp. resistance to anthelmintics has been recorded in many countries. In Saudi Arabia, there are limited data available on Parascaris spp. resistance to anthelmintics. Objective: To determine the current status of ivermectin, abamectin and praziquantel combined, and fenbendazole resistance to Parascaris spp. in horses in Saudi Arabia. Methods: Three hundred and forty-one foals from eleven different farms were examined by faecal egg count (FEC). The foals were all Arab horses aged 17.2 ± 4.5 (SD) months. Ivermectin (n = 46 foals), abamectin and praziquantel combi...
Collas C, Sallé G, Dumont B, Cabaret J, Cortet J, Martin-Rosset W, Wimel L, Fleurance G.The spread of anthelmintic resistance in equine strongyle nematodes has become a major problem, advocating for the development of alternative control for strongyles. Our study consisted of both in vivo and in vitro experiments. We investigate for the first time the efficacy of a short-term consumption of tannin-rich sainfoin (Onobrychis viciifolia) or extra proteins in naturally infected horses. We used 30 horses allocated into three groups of 10 individuals that received for 18 days either (i) a tannin-rich diet with 70% DM sainfoin pellets (Sd), (ii) a protein-rich diet with 52% DM Italian r...
Montes Cortés MG, Fernández-García JL, Habela Martínez-Estéllez MÁ.Equine piroplasmoses are enzootic parasitic diseases distributed worldwide with high incidence in tropical and subtropical regions. In Spain, there is insufficient epidemiological data about equine piroplasmoses. The main aim of the present study was therefore to estimate the prevalence of Theileria equi and Babesia caballi in five regions and obtain information about the risk factors. This study was conducted in the central and south-western regions of Spain, using indirect fluorescence antibody testing (IFAT) in 3,100 sera samples from apparently healthy horses of different ages, breeds, coa...
Rose Vineer H, Vande Velde F, Bull K, Claerebout E, Morgan ER.Gastrointestinal nematodes present a major threat to the health and welfare of equids worldwide. Anthelmintic resistance (AR) is increasingly reported and challenges effective control in horses and ponies in many regions. The use of faecal worm egg counts (FECs) to support targeted treatment (FEC-TT) and targeted selective treatment (FEC-TST) has been promoted as an effective deworming strategy that may prolong the useful life of anthelmintics and reduce the costs associated with parasite control. However, treatment applied at set intervals or on pre-determined dates remains common. A structur...
Coultous RM, Raftery AG, Shiels BR, Sutton DGM, Weir W.Sarcocystis fayeri is a canine protozoan parasite with an equine intermediate host. Historically classified as an incidental pathogen, recent literature has described the toxic effects of Sarcocystis fayeri in human food poisoning, and highlighted potential involvement in equine neuromuscular disease. Until now, horses were believed to be the exclusive intermediate host. This study reports the first molecular confirmation of S. fayeri in a donkey, and gives rise to the consideration of donkeys being a potential reservoir for the parasite. This finding is of particular importance in understandi...
Gizaw Y, Megersa M, Fayera T.Dourine is a venereal transmitted trypanosomosis causing a major health problem threatening equines worldwide. The origin and identification of Trypanosoma equiperdum within the subgenus Trypanozoon is still a subject of debate. Unlike other trypanosomal infections, dourine is transmitted almost exclusively by coitus. Diagnosis of dourine has continued to be a challenge, due to limited knowledge about the parasite and host-parasite interaction following infection. The pathological lesions caused by the diseases are poorly described and are observed mainly in the reproductive organs, in the ner...
Suganuma K, Yamasaki S, Molefe NI, Musinguzi PS, Davaasuren B, Mossaad E, Narantsatsral S, Battur B, Battsetseg B, Inoue N.Dourine is caused by Trypanosoma equiperdum via coitus with an infected horse. Although dourine is distributed in Equidae worldwide and is listed as an internationally important animal disease by the World Organization for Animal Health (OIE), no effective treatment strategies have been established. In addition, there are no reports on drug discovery, because no drug screening system exists for this parasite. A new T. equiperdum strain was recently isolated from the genital organ of a stallion that showed typical symptoms of dourine. In the present study, we adapted T. equiperdum IVM-t1 from...
Bak EJ, Jean YH, Woo GH.Four thoroughbred horses showing lameness, ataxia, circling, depression, recumbency, and seizures, were examined. The horses had gross, pale- to dark-red manifestations and foci in the central nervous system (CNS). Multifocal to coalescing eosinophilic necrotizing encephalomyelitis was observed histologically in the CNS along with intact or degenerated nematodes. Nematodes had polymyarian-coelomyarian musculature, a smooth thin cuticle, and intestines lined by multinucleated cells with microvilli. These traits suggested the nematodes belonged to the family Protostrongylidae, which includes Par...
Roncoron C, Fagiolo A, Amoruso C, De Liberato C.Species of Anoplocephalidae are cestodes affecting equines worldwide and causing many intestinal disorders. Between October 2010 and September 2013, 284 faecal samples of horses originating from Lazio Region (Central Italy) were tested for the presence of Anoplocephala sp. eggs by a classic copromicroscopic technique. Data regarding pasture‑dependence/non dependence, age, and sex of the horses were also collected. Statistical analysis, aimed at detecting possible associations between these variables and Anoplocephala sp. prevalence, was performed. Anoplocephala sp. eggs were found in 13% of ...
Venturi SS, da Silva AF, Frazão-Teixeira E, de Oliveira FCR, Consalter A, Padilha FGF, Fonseca ABM, Ferreira AMR.The aim of this study was to perform a survey on the prevalence of anti-Toxoplasma gondii antibodies in horses from Rio de Janeiro State, Brazil. From 2012 to 2013, a total of 624 blood samples were collected from horses from the eight regions comprising Rio de Janeiro State (Baixadas Litorâneas, Serrana, Norte Fluminense, Noroeste Fluminense, Centro-Sul, Metropolitana, Médio Paraíba, and Costa Verde). All sera samples were tested for anti-T. gondii antibodies by performing the modified agglutination test with a cut-off of 1:25. Positive serology for T. gondii was detected in 22.8% (142/624...
Pérez-Godínez EA, Lagunes-Zarate J, Corona-Hernández J, Barajas-Aceves M.Disposal of animal manure without treatment can be harmful to the environment. In this study, samples of four zoo animal dungs and one horse dung were pre-composted in two ways: (a) traditional composting and (b) bokashi pre-composting for 1month, followed by vermicomposting for 3months. The permanence (PEf) and reproductive potential (RP) of Eisenia foetida as well as the quality of vermicompost were evaluated. The PEf values and RP index of E. foetida were higher for samples pre-composted using the traditional composting method (98.7-88% and 31.85-16.27%, respectively) followed by vermicompo...
Leathwick DM, Sauermann CW, Geurden T, Nielsen MK.A previously described model for the dynamics of the parasitic stages of Parascaris spp. was modified to include eggs outside the host and the genetics of anthelmintic resistance before being used to address questions regarding the development of resistance. Three broad questions were addressed; i) How sustainable is the current common practice of treating foals monthly for their first year of life (i.e. 12 treatments/year)? ii) Does the timing of treatments have an effect on resistance development? (i.e. do certain treatments select for resistance more strongly than others?), and iii) How sus...
Beasley AM, Kotze AC, Allen K, Coleman GT.The macrocyclic lactone (ML) drugs are central to the control of equine strongyles but recent international reports raise concerns about reduced efficacy of these drugs against cyathostomins. The objectives of the present study were firstly, to evaluate the efficacy of ML drugs against cyathostomins on a cross-section of Australian horse farms, and secondly, to determine the egg reappearance period (ERP) following treatment of horses with MLs. A total of 419 horses on 43 properties were treated orally with ivermectin, abamectin or moxidectin, at recommended dose rates and drug efficacy was det...
Murungi EK, Kariithi HM.The apicomplexan parasite Sarcocystis neurona causes equine protozoal myeloencephalitis (EPM), a degenerative neurological disease of horses. Due to its host range expansion, S. neurona is an emerging threat that requires close monitoring. In apicomplexans, protein kinases (PKs) have been implicated in a myriad of critical functions, such as host cell invasion, cell cycle progression and host immune response evasion. Here, we used various bioinformatics methods to define the kinome of S. neurona and phylogenetic relatedness of its PKs to other apicomplexans. We identified 97 putative PKs clust...
de Sousa SH, Paludo GR, Freschi CR, Machado RZ, de Castro MB.The aim of this report was to confirm the cause of abortion to be Theileria equi acquired transplacentally in a mare in Federal District, Brazil. The aborted fetus showed a high parasitemia of erythrocytes (80%) by the oval and Maltese cross forms of T. equi. Necropsy of the fetus demonstrated congestion of organs, jaundice, anemia and pronounced spleno- and hepatomegaly. Twelve breeding mares, including the one that aborted and her fetus, tested positive for T. equi infection by universal and multiplex PCR assay. The absence of histopathologic changes such as inflammation and necrosis in the ...
Mittelman NS, Divers TJ, Engiles JB, Gerhold R, Ness S, Scrivani PV, Southard T, Johnson AL.There are reports of horses with acute onset acquired cervical scoliosis and cutaneous analgesia. The underlying dorsal gray column myelitis that produces these neurologic signs has been only presumptively attributed to migration of Parelaphostrongylus tenuis within the spinal cord. Despite previous confirmation brain by polymerase chain reaction testing, of P. tenuis within the brain of horses by polymerase chain reaction testing, genetic testing has failed to definitively identify the presence of this parasite in cases of equine myelitis. This case report provides molecular confirmation via ...
Lyons ET, Bellaw JL, Dorton AR, Tolliver SC.Field tests were performed on Thoroughbred yearlings (n=143), evaluating efficacy of moxidectin (MOX) against ascarids and strongyles and the efficacy of an ivermectin (IVM)-praziquantel (PRAZ) combination against those nematodes and tapeworms on a farm in Central Kentucky. The study was started on March 1, 2016 and completed on August 23, 2016. Fecal samples were collected from yearlings every two weeks for counts of ascarid and strongyle eggs per gram of feces (EPGs) and for determining the presence of tapeworm eggs. MOX was given to 88 yearlings on March 1; 55 yearlings were nontreated cont...
Chaney SB, Marsh AE, Lewis S, Carman M, Howe DK, Saville WJ, Reed SM.Equine protozoal myeloencephalitis (EPM) remains a significant central nervous system disease of horses in the American continents. Sarcocystis neurona is considered the primary causative agent and its intermediate life stages are carried by a wide host-range including raccoons (Procyon lotor) in North America. S. neurona sarcocysts mature in raccoon skeletal muscle and can produce central nervous system disease in raccoons, mirroring the clinical presentation in horses. The study aimed to develop laboratory tools whereby the life cycle and various life stages of S. neurona could be better stu...
Portella LP, Cadore GC, Sangioni LA, Pellegrini LF, Fighera R, Ramos F, Vogel FS.Sarcocystis spp., Neospora spp., and Toxoplasma gondii are Apicomplexa protozoa that can infect horses. This study aimed to investigate the occurrence of antibodies against Sarcocystis spp., Neospora spp., and T. gondii in horses slaughtered in southern Brazil. The presence of histological lesions, tissue cysts, and Sarcocystis spp. DNA in the hearts of these horses was also investigated. A total of 197 paired serum and heart samples were evaluated by serology and direct microscopic examination; 50 of these samples were subjected to histopathological and PCR analyses. Antibodies against at lea...
Deng L, Li W, Zhong Z, Gong C, Cao X, Song Y, Wang W, Huang X, Liu X, Hu Y, Fu H, He M, Wang Y, Zhang Y, Wu K, Peng G.A total of 333 fecal specimens from horses in southwestern China were genotyped based on analysis of the small subunit rRNA (SSU rRNA) gene. Cryptosporidium hominis and Cryptosporidium andersoni were identified in 2 and 4 stool specimens, respectively. The identification of C. hominis was confirmed by sequence analysis of the 70-kDa heat shock protein (HSP70) and oocyst wall protein (COWP) genes. Subtyping analysis of the 60-kDa glycoprotein (GP60) gene sequence of C. hominis revealed a new rare subtype Id, named IdA15; only three Id isolates have been reported in humans to date. Multilocus ...
López López C, Ferreira LMM, García U, Moreno-Gonzalo J, Rodrigues MAM, Osoro K, Ferre I, Celaya R.The number of horses in northern Spanish mountains has increased in recent decades, but little is known about their grazing behaviour, performance and potential for foal meat production. This research aimed to study the diet selection, liveweight (LW) changes and parasitic status of dry and lactating mares, and foals' LW gains, grazing on heathlands with different botanical composition. The experimental design consisted of three vegetation types: dominated by heather (Ericaceae) species (H), dominated by gorse (Ulex gallii; G) and co-dominated by gorse and heath-grasses (G-G), with four replic...
Cavallero S, Pombi M, Perrone V, Milardi GL, D'Amelio S, Giuliani C, Gabrielli S.Larval forms of the bot-fly Gasterophilus are obligate parasites commonly found in the gastrointestinal tract of equids, causing intestinal myiasis. Five species are reported so far in Italy, mostly observed during necroscopy, located in different portion of gastrointestinal tract of equids: G. intestinalis, G. nasalis, G. inermis, G. pecorum and G. haemorrhoidalis. An unusual finding of larval Gasterophilus intestinalis deeply inserted into the diaphragmatic muscle is here reported. Due to the uncommon localization, to the absence of clinical signs related to myiasis and subsequent uncertaint...
Wilkes E, McConaghy FF, Thompson RL, Dawson K, Sangster NC, Hughes KJ.This study was performed to investigate the efficacy of a morantel-abamectin combination for the treatment of macrocyclic lactone (ML)-resistant Parascaris spp. infections in foals. Methods: Foals on five properties with a Parascaris faecal egg count (FEC) > 50 eggs per gram were used to estimate the FEC reduction (FECR) and efficacy of the anthelmintic combination. Conclusions: On all properties, resistance to ivermectin and abamectin was present and the Parascaris FECR in foals administered the morantel-abamectin combination was > 99%, indicating that this combination effective...
Horak IG, Heyne H, Halajian A, Booysen S, Smit WJ.The aim of the study was to determine the species spectrum of ixodid ticks that infest horses and donkeys in South Africa and to identify those species that act as vectors of disease to domestic livestock. Ticks were collected opportunistically from 391 horses countrywide by their owners or grooms, or by veterinary students and staff at the Faculty of Veterinary Science, University of Pretoria. Ticks were also collected from 76 donkeys in Limpopo Province, 2 in Gauteng Province and 1 in North West province. All the ticks were identified by means of a stereoscopic microscope. Horses were infest...
Tzelos T, Barbeito JS, Nielsen MK, Morgan ER, Hodgkinson JE, Matthews JB.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...
Darghouth MA.Several species of piroplasms of livestock are present in Tunisia; some of them are of high veterinary importance. This paper reviews the species already reported in Tunisia on the basis of clinical observations, parasitological routine diagnostic and serological surveys, as well as those considered as potentially present according to epidemiological argumentations. The genus Theileria includes four species reported in Tunisia: T. annulata, T. buffeli, T. ovis, and T. equi. The ovine malignant theileriosis agent, T. lestoquardi, appears to be absent in Tunisia. Five species belonging to the ge...
Abedi V, Razmi G, Seifi H, Naghibi A.Equine piroplasmosis is a tickborne disease of equids with worldwide distribution, caused by Theileria equi and Babesia caballi. The aim of this study was molecular detection of T. equi and B. caballi in donkeys in northeastern Iran and investigate the association between positivity of piroplasm infection and host-related factors. In the present study, Blood samples were collected from 106 apparently healthy donkeys (Equus asinus) in North Khorasan province, Iran. Blood smears were prepared and stained by giemsa method. DNA was extracted from blood and then multiplex-PCR was done for detection...
Tirosh-Levy S, Steinman A, Levy H, Katz Y, Shtilman M, Gottlieb Y.Equine piroplasmosis is a highly endemic protozoan disease of horses worldwide, caused by Theileria equi and Babesia caballi. While most horses in endemic areas are subclinically infected, the mechanisms leading to clinical outcome are vastly unknown. Moreover, since clinical signs of disease are not specific, and the prevalence in endemic areas is high, it is difficult to determine if equine piroplasmosis is the cause of disease. To identify possible mechanisms leading to the clinical outcome in an endemic area, we compared parasite loads and genotypes in clinically and subclinically infected...
Pfister K, van Doorn D.Regular anthelmintic treatment has contributed to anthelmintic resistance in horse helminths. This mass anthelmintic treatment was originally developed owing to a lack of larvicidal drugs against Strongylus vulgaris. The high prevalence of anthelmintic resistance and shortening of strongyle egg reappearance period after avermectins/moxidectins requires epidemiologically appropriate and sustainable measures. Selective anthelmintic treatment is a much-needed deworming approach: More than 50% of adult horses manifest no strongyle egg excretion. In this article, selective anthelmintic treatment pr...
Eysker M, Boersema JH, Kooyman FN.A controlled and critical test on the efficacy of ivermectin against larval and adult stages of the cyathostomes was carried out in six yearling castrated male Shetland ponies. The ponies grazed together as one group from 3 May to 4 October 1990, after which they were housed. Three ponies were treated with ivermectin on 29 October while the others served as controls. The shedding of helminths in the faeces was followed in all ponies until necropsy on 14 November. Comparison of worm counts of both groups before and after necropsy showed no evidence for an effect of ivermectin against inhibited ...
Edwards GT.The stomachs of 448 horses from northern England and Wales were examined for Gasterophilus larvae, and 237 (52.7%) were found to be infected with G. intestinalis. Larvae were present in stomachs examined during each month of the year except August. Second instar larvae occurred from September through February and third instars were present from November through July. Adult fly activity began in August as indicated by the presence of eggs on horses. The life-cycle of G. intestinalis in northern England and Wales is outlined from the data presented. The mean instar burdens were 15.7 second and 3...
Ghafar A, Abbas G, Beasley A, Bauquier J, Wilkes EJA, Jacobson C, McConnell E, El-Hage C, Carrigan P, Cudmore L, Tennent-Brown B, Hurley J....This review is aimed to (i) appraise the literature on the use of molecular techniques for the detection, quantification and differentiation of gastrointestinal helminths (GIH) of equids, (ii) identify the knowledge gaps and, (iii) discuss diagnostic prospects in equine parasitology. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for systematic reviews, we retrieved 54 studies (horses: 50/54; donkeys and zebras: 4/54) from four databases. Polymerase chain reaction (PCR) was employed in all of the studies whereas PCR amplicons were sequenced...
Yadav SC, Kumar R, Manuja A, Goyal L, Gupta AK.In present communication, we report an outbreak of Trypanosoma evansi in equine herd n = 30 (horse and mules) which, were reared in fly proof stables as well as in open paddock maintained under semi-intensive system of management, and its effective control using trypanocidal drug. The infection was monitored by antibody ELISA up to 180 days post-treatment (PT). A total of 8 out of 14 equines (57.14 %) which were maintained only in open paddocks were found positive with T. evansi infection parasitologically. The infected animals were treated with quinapyramine methyl sulphate and chloride c...
Rendle DI, Cottle HJ, Love S, Hughes KJ.In equids, chorioptic mange is a common dermatitis for which there are no licensed medications in the uk. Doramectin and fipronil are licensed for the control of ectoparasites in other species and were evaluated for the treatment of 17 cases of chorioptic mange in 13 equids. Equids were included if clinical findings were indicative of chorioptic mange, chorioptes mites were positively identified and concurrent disease that could affect response to disease was not evident. A random number table was used to allocate subjects to receive doramectin (group D, eight animals) or fipronil (group F, ni...
Nielsen MK, Fritzen B, Duncan JL, Guillot J, Eysker M, Dorchies P, Laugier C, Beugnet F, Meana A, Lussot-Kervern I, von Samson-Himmelstjerna G.Development of resistance of several important equine parasites to most of the available anthelmintic drug classes has led to a reconsideration of parasite control strategies in many equine establishments. Routine prophylactic treatments based on simple calendar-based schemes are no longer reliable and veterinary equine clinicians are increasingly seeking advice and guidance on more sustainable approaches to equine parasite control. Most techniques for the detection of equine helminth parasites are based on faecal analysis and very few tests have been developed as diagnostic tests for resistan...
Ybañez AP, Ybañez RHD, Talle MG, Arreglo RMT, Geens MJC, Villas JGI, Villar SR, Laruga CL, Cao S, Moumouni FPA, Liu M, Igarashi I, Xuan X.Theileria equi and Babesia caballi are tick-borne protozoan parasites that can cause anemia in horses. In the Philippines, serological detection of these parasites has only been reported in the Northern area (Luzon). In this study, 105 horses from Cebu and Bohol, Philippines were tested using peripheral blood smear examination (PBSE), immunochromatographic test (ICT) strips, and PCR. Clinical history, presenting clinical signs and complete blood count were obtained. Results revealed that although all horses were negative using PBSE, 23 (21.9%) were positive (12 for T. equi, and 11 for B. cabal...
Monahan CM, Chapman MR, Taylor HW, French DD, Klei TR.Three groups of foals were raised under different management programs in this study: Group 1 (n = 6) and Group 2 (n = 6) were raised with their dams on pasture; Group 3 foals (n = 5) were raised under parasite-free conditions. Mares and foals of Group 1 received daily pyrantel tartrate (PT) treatment with their pelleted feed ration, whereas mares and foals of Groups 2 and 3 received only the pelleted ration. Pasture-reared foals were weaned and moved to a heavily contaminated pasture for 5 weeks. Group 1 foals continued to receive daily PT treatment whereas Group 2 foals received only the pell...
Sevá Ada P, Funada MR, Souza Sde O, Nava A, Richtzenhain LJ, Soares RM.The aim of this study was to assess the occurrence of Cryptosporidium in domestic animals in rural properties surrounding rain forest fragments within the municipality of Teodoro Sampaio, southeastern Brazil. Conventional sucrose flotation method followed by molecular characterization of the parasites by sequencing PCR products amplified from SSU rRNA gene were used. Stool samples were collected from domestic animals raised as pets and livestock in all rural properties surrounding three forest fragments. Samples from cattle (197), equine (63), pigs (25), sheep (11), and dogs (28) were collecte...
Baldacchino F, Cadier J, Porciani A, Buatois B, Dormont L, Jay-Robert P.Urine volatiles from different ungulates (cows, horses and sheep) were tested as bait for tabanids in southeastern France using Nzi traps during the early summer of 2011. Tabanus bromius Linnaeus, 1758 and Atylotus quadrifarius (Loew, 1874) (both: Diptera: Tabanidae) were the most captured species, respectively representing 57% and 41% of all tabanids collected (all of which were female). Horse urine significantly increased catches of T. bromius (1.6-fold) and A. quadrifarius (3.5-fold), and sheep urine significantly increased catches of A. quadrifarius (2.5-fold). In parallel, an electroanten...
Kornaś S, Gawor J, Cabaret J, Molenda K, Skalska M, Nowosad B.The prevalence of infection with cyathosthomes of horses is high worldwide. Identification of species on infective larvae based on available morphological keys is not fully accurate and the aim of the present study was to provide a reliable identification key of cyathostomes infective larvae. At the abattoir, horse large intestines were examined and the cyathostomes females extracted and identified. The eggs from uteruses of identified cyathostomes females were used for breeding the infective larvae. Morphological parameters of Cyathostominae infective larvae, i.e. the length of the larvae wit...
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...
Lyons ET, Kuzmina TA, Tolliver SC, Collins SS.Early development and maturation of species of small strongyles have not been studied extensively. Most information is on the first appearance of strongyle eggs in feces of foals. However, species cannot be determined in this manner because of similarity of the morphological features of the eggs. To determine more definitive knowledge on development and species composition of natural infections of small strongyles, eight equid foals were necropsied and examined at various ages (31 to 92 days of age). The entire contents of the large intestine were examined, and all worms (6,671) recovered were...
Tatz AJ, Segev G, Steinman A, Berlin D, Milgram J, Kelmer G.There is a consensus in the veterinary literature that Parascaris equorum (ascarid) impaction carries a poor prognosis. Hence surgery is often delayed and foals are often subjected to euthanasia after diagnosis of ascarid impaction is established. Our clinical impression was that ascarid impaction carries a better prognosis than previously reported. Objective: Our expectation was that manually evacuating the impaction into the caecum, thus refraining from opening the small intestine, would improve the prognosis for survival of horses with ascarid impaction. The aim of this study was to examine...
Avarzed A, Igarashi I, De Waal DT, Kawai S, Oomori Y, Inoue N, Maki Y, Omata Y, Saito A, Nagasawa H, Toyoda Y, Suzuki N.Monoclonal antibody (MAb) BEG3 was produced against Babesia equi parasites to define a species-specific antigen for diagnostic use. The MAb reacted with single, paired, and Maltese cross forms of B. equi, and no reaction was observed with this MAb on acetone-fixed Babesia caballi, Babesia ovata, or Babesia microti parasites in the indirect immunofluorescent antibody test. Confocal laser and immunoelectron microscopic studies showed that the antigen which was recognized by this MAb was located on the surface of B. equi parasites. This MAb recognized a 19-kDa protein of B. equi antigen and did n...
Bahrami S, Ghadrdan AR, Mirabdollahi SM, Fayed MR.A total of 105 blood samples from healthy horses from different stables in Yazd province, center of Iran, were examined for the presence of Theileria equi infection using parasitological and molecular methods. Out of the 105 samples, the parasitological method detected T. equi infection in 5 (4.76%) cases while the PCR method gave 24 (22.86%) positive results. Age, gender and breed were not determined as risk factors for T. equi infection in this study. Since blood samples were taken from healthy animals, this implies that 22.86% of horses had subclinical theileriosis in the current study. In ...
Hernández JÁ, Sánchez-Andrade R, Cazapal-Monteiro CF, Arroyo FL, Sanchís JM, Paz-Silva A, Arias MS.An approach to preventing strongyle infection in horses was tested, comprising rotational pasturing and the administration of spores of two parasiticidal fungi, Mucor circinelloides and Duddingtonia flagrans. Twenty-two adult Spanish Sport Horses were dewormed with ivermectin (1 mg pour-on/kg body weight) and then randomly divided into three groups. G-1 was maintained with continuous grazing, and G-2 and G-3 were kept on a four-paddock rotation system. Commercial pelleted feed (2.5 kg/horse) was supplied to G-1 and G-2 twice a week; horses in G-3 received pellets containing 2 × 10 spores/kg o...
Bjørn H, Sommer C, Schougård H, Henriksen SA, Nansen P.This study was undertaken to establish whether anthelmintic resistance was present in nematode parasites of horses in Denmark. Sixteen horse farms were selected for faecal egg count reduction (FECR) tests to measure the efficacy of the anthelmintic used. Resistance to benzimidazole anthelmintics was found on 13 of the 16 farms, with FECR values ranging from 80.0% to -101.3%. On the remaining 3 farms FECR was 100.0%, 99.3% and 97.2%. Results of a questionnaire study on anthelmintic usage, parasite control measures and management practices showed that horses in this study were treated on average...
Lyons ET, Tolliver SC, Collins SS.Two field tests (A and B) were conducted in Thoroughbred weanlings born in 2008 and 2009 on a farm (BC) in Central Kentucky. The purpose was to determine the current efficacy of moxidectin (MOX) and ivermectin (IVM) on small strongyles by pre- and posttreatment counts of eggs per gram of feces (EPGs) in this geographical area. In previous parasite studies in horses on this farm and in horses on numerous other farms in this area, cultures of feces indicated the strongyle larvae were all small strongyles. Therefore, the strongyle eggs in the EPG counts are considered small strongyles. Designatio...
Tydén E, Morrison DA, Engström A, Nielsen MK, Eydal M, Höglund J.The large roundworm of horses, Parascaris equorum is considered ubiquitous in breeding operations, and is regarded as a most important helminth pathogen of foals. Over the past decade, this parasite has been reported increasingly resistant to anthelmintic drugs worldwide. This paper reports analysis of the population genetic structure of P. equorum. Adult parasites (n=194) collected from Sweden, Norway, Iceland, Germany, Brazil and the USA were investigated by amplified restriction fragment length polymorphism (AFLP) analysis. The genetic variation was low (Hj=0.12-0.4), for the global populat...
Blutke A, Hamel D, Hüttner M, Gehlen H, Romig T, Pfister K, Hermanns W.In Europe, cystic echinococcosis is rare in horses and is mostly diagnosed at slaughter or postmortem examination. Equine cystic echinococcosis can be caused by various Echinococcus taxa, but only Echinococcus equinus (the "horse strain") is known to produce fertile cysts. In Europe, E. equinus appears to be endemic in Great Britain, Ireland, Spain, and Italy and has sporadically been reported in Belgium and Switzerland. The present report describes the first case of a molecularly confirmed E. equinus infection in a horse foaled and raised in Germany. The 19-year-old mare was presented for exa...
Nielsen MK.Given the increasing levels of anthelmintic resistance in equine parasites, parasitologists now recommend traditional treatment approaches to be abandoned and replaced by more sustainable strategies. It is of crucial importance to facilitate veterinary involvement to ensure that treatment decisions are based on parasitic knowledge. Despite recommendations given for the past two decades, strategies based on the selective therapy principle have not yet been implemented on a larger scale in equine establishments. In contrast, treatment regimens appear to be derived from recommendations originally...
Matthee S, Krecek RC, McGeoch MA.The intestinal helminth communities of 8 horses, 12 donkeys, 21 Hartmann's mountain zebras, and 44 Burchell's zebras were compared using the original data from 6 studies in South Africa and Namibia. Necropsy and worm recovery techniques were comparable between the studies. Sixty helminth species (58 nematode, 1 cestode, and 1 trematode species) were recorded. There were significant differences in the helminth community structures of the 4 Equus species. The helminth communities of the 2 closely related zebra subspecies were most similar, and they jointly shared 7 helminth species with donkeys ...
Drudge JH, Lyons ET.The critical test is the primary method used for the efficacy evaluation of drugs against the major internal parasites (bots, ascarids, large strongyles, small strongyles, and pinworms) of the horse. The critical test determines: (1) spectrum of activity, (2) effectiveness of removal, (3) pattern of discharge, and (4) physical condition of each species of these parasites. General characteristics of the major parasitisms of the horse are discussed briefly. Criteria of the critical test also are considered including: (1) number of tests, (2) strain variation and drug resistance, (3) selection of...
Burk SV, Dangoudoubiyam S, Brewster-Barnes T, Bryant UK, Howe DK, Carter CN, Vanzant ES, Harmon RJ, Kazacos KR, Rossano MG.Currently, diagnosis of Parascaris equorum infection in equids is limited to patent infections. The goals of this study were to culture P. equorum larvae in vitro and identify excretory-secretory (ES) products for prepatent diagnostic testing. Parascaris equorum L2/L3 larvae were hatched and cultured for up to 3 weeks for ES product collection. Fifth stage (L5) P. equorum were also cultured for ES product collection. Examination of ES fractions by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and silver stain revealed L2/L3 products ranging from 12-94 kDa and L5 products...
Tandon R, Kaplan RM.A larval development assay (LDA, DrenchRite) was evaluated to determine the effectiveness of this method in detecting anthelmintic resistance in cyathostomin nematodes of horses. A total of 15 horse farms from Georgia and South Carolina (USA) and Population S ponies from the University of Kentucky (USA) were included in this study. Nematode eggs were extracted from pooled fecal samples and placed into the wells of a DrenchRite plate for testing against thiabendazole (TBZ), levamisole (LEV) and 2 ivermectin (IVM) analogs (IVM-1, IVM-2). After a 7-day incubation larvae in each well were counted ...
