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.
Prichard RK, Geary TG.Macrocyclic lactone (ML) anthelmintics are the most important class of anthelmintics because of our high dependence on them for the control of nematode parasites and some ectoparasites in livestock, companion animals and in humans. However, resistance to MLs is of increasing concern. Resistance is commonplace throughout the world in nematode parasites of small ruminants and is of increasing concern in horses, cattle, dogs and other animals. It is suspected in Onchocerca volvulus in humans. In most animals, resistance first arose to the avermectins, such as ivermectin (IVM), and subsequently to...
Peng TL, Armiladiana MM, Ruhil HH, Maizan M, Choong SS.The occurrence of Setaria digitata in a horse is reported for the first time in Malaysia. An 8-year-old Thoroughbred cross mare was referred to the University Veterinary Clinic with the primary complaint of corneal opacity and excessive eye discharge. After initial treatment with Terramycin eye ointment, corneal opacity cleared partially to reveal a moving thread-like cylindrical worm in the anterior chamber of the eye. The parasite was successfully removed surgically, and examination under the light microscope revealed that the isolated worm (length = 45 mm) was a 5th stage larva of S. ...
Tydén E, Enemark HL, Franko MA, Höglund J, Osterman-Lind E.Strongylus vulgaris is considered the most pathogenic nematode parasite of the horse. Frequent deworming programs since the 1970s have reduced the prevalence of S. vulgaris to low levels, but to the price of widespread benzimidazole resistance in the small strongyles (cyathostominae) and ivermectin resistance especially in the equine roundworm Parascaris spp. To slow down the progression of anthelmintic resistance in Sweden, horse anthelmintics were made prescription only medicine in 2007 and selective therapy principles were introduced. This means that only individuals with high egg excretion...
Tydén E, Enemark HL, Franko MA, Höglund J, Osterman-Lind E.Strongylus vulgaris is considered the most pathogenic nematode parasite of the horse. Frequent deworming programs since the 1970s have reduced the prevalence of S. vulgaris to low levels, but to the price of widespread benzimidazole resistance in the small strongyles (cyathostominae) and ivermectin resistance especially in the equine roundworm Parascaris spp. To slow down the progression of anthelmintic resistance in Sweden, horse anthelmintics were made prescription only medicine in 2007 and selective therapy principles were introduced. This means that only individuals with high egg excretion...
Onyiche TE, Suganuma K, Igarashi I, Yokoyama N, Xuan X, Thekisoe O.Equine Piroplasmosis (EP) is a tick-borne disease caused by apicomplexan protozoan parasites, and . The disease is responsible for serious economic losses to the equine industry. It principally affects donkeys, horses, mules, and zebra but DNA of the parasites has also been detected in dogs and camels raising doubt about their host specificity. The disease is endemic in tropical and temperate regions of the world where the competent tick vectors are prevalent. Infected equids remain carrier for life with infection, whilst, infection with is cleared within a few years. This review focuses on...
Equine trypanosomosis is a complex of infectious diseases called dourine, nagana and surra. It is caused by several species of the genus Trypanosoma that are transmitted cyclically by tsetse flies, mechanically by other haematophagous flies, or sexually. Trypanosoma congolense (subgenus Nannomonas) and T. vivax (subgenus Dutonella) are genetically and morphologically distinct from T. brucei, T. equiperdum and T. evansi (subgenus Trypanozoon). It remains controversial whether the three latter taxa should be considered distinct species. Recent outbreaks of surra and dourine in Europe illustrate ...
Boucheikhchoukh M, Mechouk N, Benakhla A, Raoult D, Parola P.The sheep ked, Melophagus ovinus, and the forest fly, Hippobosca equina, are parasitic dipteran insects of veterinary importance. As hematophagous insects, they might be considered as potential vectors of diseases which may be transmissible to humans and animals. The purpose of this study was to present initial primary data about these two species in Algeria. To do so, we conducted a molecular survey to detect the presence of bacterial DNA in flies collected in Algeria. A total of 712 flies including, 683 Melophagus ovinus and 29 Hippobosca equina were collected from two regions in northeaster...
Nurcahyo W, Yowi MRK, Hartati S, Prastowo J.Horses have a strategic and vital role to play in the lives of the people of Sumba Island, East Nusa Tenggara Province. They act as social animals that are involved in death ceremonies, horse races, and during pasola, thereby supporting tourism, and are given away as dowry in wedding ceremonies. This study aimed to investigate the prevalence of trypanosomiasis among horses in four districts of Sumba Island by examining clinical symptoms and detecting parasites, antibodies, and other factors that are related to infection in horses. Methods: We studied a total of 211 horses that belonged to 88 ...
Regnier A, Martin C, Semin MO, Lienard E, Geffre A, Douet JY, Raymond-Letron I.An 18-month-old Arabian-English filly resident in southwest France was referred for evaluation of a conjunctival mass in the right eye (OD). A pink, solid, and mobile nodular formation, measuring approximately 1.2 × 0.8 cm was found under the superior nasal bulbar conjunctiva during an ophthalmic examination that was otherwise normal. The mass was surgically removed using a standing procedure. Cytological examination of fine-needle aspirates from the mass revealed a mixed eosinophilic-lymphocytic inflammation. Histological examination confirmed the dense and diffuse eosinophilic-lymphocyti...
Hreinsdóttir I, Hreinsdóttir A, Eydal M, Tysnes KR, Robertson LJ.In Iceland, there is at least 1 horse for every 5 human inhabitants, mostly kept on uncultivated rangelands. Although the Icelandic horse is considered robust compared with other breeds, it is nevertheless susceptible to disease. Few studies have investigated the prevalence of intestinal parasites in horses in Iceland. The purpose of this study was to determine the prevalence of the tapeworm, Anoplocephala perfoliata, in horses in Iceland and to explore associations between intensity of infection and the severity of macroscopic pathological lesions in this population. In addition, the relation...
Hay AN, Witonsky SG, Lindsay DS, LeRoith T, Zhu J, Kasmark L, Leeth CM. is a ubiquitous parasite in the eastern United States, which is the principal causative agent in the neurologic disorder equine protozoal myeloencephalitis (EPM). While much is known about this protozoa's life cycle in its natural host, the opossum (), little is known of how it acts in the aberrant equine host, which displays a high incidence of exposure with a relatively low rate of morbidity. For this study, we employed the popular interferon gamma knockout mouse model to determine the potential for recrudescence of infection after treatment with the anticoccidial drug diclazuril. Mice wer...
Saeed MA, Beveridge I, Abbas G, Beasley A, Bauquier J, Wilkes E, Jacobson C, Hughes KJ, El-Hage C, O'Handley R, Hurley J, Cudmore L, Carrigan P....Equine gastrointestinal nematodes (GINs) have been the subject of intermittent studies in Australia over the past few decades. However, comprehensive information on the epidemiology of equine GINs, the efficacy of available anthelmintic drugs and the prevalence of anthelmintic resistance (AR) in Australasia is lacking. Herein, we have systematically reviewed existing knowledge on the horse GINs recorded in Australia, and main aspects of their pathogeneses, epidemiology, diagnoses, treatment and control. Methods: Six electronic databases were searched for publications on GINs of Australian hors...
Wilkes EJA, Woodgate RG, Raidal SL, Hughes KJ.This study investigated the impact of variability in Parascaris spp. and strongyle faecal egg counts (FEC) from foals on treatment decision-making and detection of a patent infection. A single faecal sample was collected once daily for three days from 53 foals and a FEC was performed on three separate portions of each sample (total of nine egg counts per foal). Differences in the decision to administer an anthelmintic using the results of a single count (C), the mean of three (X¯) or nine counts (X¯) and the upper 5% confidence limit of the gamma confidence interval (CI) of the estimate of t...
Devi CN, Borthakur SK, Patra G, Singh NS, Tolenkhomba TC, Ravindran R, Ghosh S.Information pertaining to parasitic fauna and parasitic diseases in Manipuri ponies in India is not available. Moreover, no systematic studies have been undertaken on cutaneous habronemosis in Manipuri ponies which is a common skin problem of Manipuri ponies as reported by pony owners. Keeping in the view of the importance of parasitic infections in veterinary health coverage particularly in Manipuri ponies, the present study was planned. A survey of natural cases of cutaneous habronemosis followed by molecular confirmation of species involved and treatments were done. Out of 200 ponies examin...
Ramírez-Hernández A, Polo G, Robayo-Sánchez LN, Cruz-Maldonado OA, Imbacuán-Pantoja WO, Cortés-Vecino JA.Working equids are used in different countries for numerous purposes and regularly are crucial for multiple communities' income and profit. Historically, in Bogotá D.C. they were used as animal-powered vehicles but in 2013 it was initiated a substitution and adoption program as a result of society pressure and lawful processes. Infectious diseases and mainly parasitic diseases, poses a threat in the health and productivity of these animals. Our aim was to identify, by coproparasitological methods, the gastrointestinal and pulmonary parasite species infecting working horses submitted to the me...
Sauermann CW, Nielsen MK, Luo D, Leathwick DM.Previously described models for the free-living and parasitic phases of the cyathostomin life-cycle were combined into a single model for the complete life-cycle. The model simulates a single free-living population on pasture utilising parasite egg output from the horses and localised temperature and rainfall data to estimate infective larval density on herbage. Multiple horses of different ages are possible, each with an individualised anthelmintic treatment programme. Genotypes for anthelmintic resistance are included allowing for up to three resistance genes with 2 alleles each. Because lit...
Schott HC, Estrada-Coates A, Alva-Trujillo M, Petersen AD, Kinsley MA, Esser MM, Casillas J, Garcia-Seco E, Madariaga-Najera M, Fernando Martínez JA....There is great need for veterinary care for working equids worldwide. Addressing this need provides an opportunity for veterinary students to gain primary care experience. An annual two week collaborative outreach and educational program with Michigan State University (MSU), the Universidad Nacional Autónoma de México (UNAM) and the Universidad Veracruzana (UV) was developed to provide care for working equids in rural Mexican communities. From 2017 to 2019 24 US veterinary students and 25 Mexican veterinary students, interns and residents examined, vaccinated and dewormed more than 2200 equi...
Elghryani N, Duggan V, Relf V, de Waal T.Knowledge regarding helminth control strategies and nematode infection of horses in Ireland is limited and only one study has been published recently. This present study was designed to investigate the current helminth control strategies followed by horse owners in Ireland. A questionnaire was formulated to collect data on general grazing, pasture management and deworming strategies including the use of fecal egg counts. Questionnaires were emailed to 700 members of the Irish Thoroughbred Breeders Association and Horse Sport Ireland. Only 78 questionnaires were returned. Respondents indicated ...
Walshe N, Duggan V, Cabrera-Rubio R, Crispie F, Cotter P, Feehan O, Mulcahy G.The interactions between parasitic helminths and gut microbiota are considered to be an important, although as yet incompletely understood, factor in the regulation of immunity, inflammation and a range of diseases. Infection with intestinal helminths is ubiquitous in grazing horses, with cyathostomins (about 50 species of which are recorded) predominating. Consequences of infection include both chronic effects, and an acute inflammatory syndrome, acute larval cyathostominosis, which sometimes follows removal of adult helminths by administration of anthelmintic drugs. The presence of cyathosto...
Gharbi M, Drissi G, Darghouth MA.A preliminary study was carried out to examine the population dynamics of ticks on 24 pure Arabian horses. The horses were monitored monthly over one year in the Ghardimaou region of north-west Tunisia. A total of 120 adult ticks were collected and identified, leading to the estimation of different parasitological indicators. The ticks belonged to a single genus (Hyalomma) and three species: H. scupense (59%), H. marginatum (28%) and H. excavatum (13%) (p < 0.001). The mean infestation prevalence was 29.5%; the highest prevalence was observed for H. scupense (41.7%) (p 0.05), but the propo...
Nielsen MK, Sauermann CW, Leathwick DM.Anthelmintic resistance is widespread in equine cyathostomin populations across the world, and with no new anthelmintic drug classes in the pharmaceutical pipeline, the equine industry is forced to abandon traditional parasite control regimens. Current recommendations aim at reducing treatment intensity and identifying high strongylid egg shedders in a targeted treatment approach. But, virtually nothing is known about the effectiveness of these recommendations, nor their applicability to different climatic regions, making it challenging to tailor sustainable recommendations for equine parasite...
Gold S, Regan CE, McLoughlin PD, Gilleard JS, Wilson AJ, Poissant J.Variability in host resistance or tolerance to parasites is nearly ubiquitous, and is of key significance in understanding the evolutionary processes shaping host-parasite interactions. While ample research has been conducted on the genetics of parasite burden in livestock, relatively little has been done in free-living populations. Here, we investigate the sources of (co)variation in strongyle nematode faecal egg count (FEC) and body condition in Sable Island horses, a feral population in which parasite burden has previously been shown to negatively correlate with body condition. We used the ...
Yasine A, Ashenafi H, Geldhof P, Bekana M, Tola A, Van Brantegem L, Van Soom A, Duchateau L, Goddeeris BM, Govaere J.Trypanosoma equiperdum (T. equiperdum) causes dourine, a venereally transmitted infection in horses. Purification of semen by single layer centrifugation (SLC) has been proven to be successful in reducing venereally transmitted diseases when dealing with other pathogens. The objective of this study was to evaluate the purification of T. equiperdum spiked semen by SLC. Semen was spiked using cryopreserved T. equiperdum stabilates (Dodola strain isolate 943). In total, 6 concentrations, varying from 10 to >5 × 10 trypanosomes, were added to semen samples. Subsequently, SLC was performed ...
Mitchell CJ, O'Sullivan CM, Pinloche E, Wilkinson T, Morphew RM, McEwan NR.Next-generation sequencing of DNA from nematode eggs has been utilised to give the first account of the equine 'nemabiome'. In all equine faecal samples investigated, multiple species of Strongylidae were detected, ranging from 7.5 (SEM 0.79) with 99+% identity to sequences in the NCBI database to 13.3 (SEM 0.80) with 90+% identity. This range is typical of the number of species described previously in morphological studies using large quantities of digesta per animal. However, the current method is non-invasive; relies on DNA analysis, avoiding the need for specialist microscopy identificatio...
Yasine A, Daba M, Ashenafi H, Geldhof P, Van Brantegem L, Vercauteren G, Demissie T, Bekana M, Tola A, Van Soom A, Duchateau L, Goddeeris B, Govaere J.Dourine, caused by Trypanosoma equiperdum, is a life-threatening venereal disease in equidae. So far, there is no clear evidence on how and when stallions become infectious, nor which tissues are affected by the parasite in diseased animals. Post-infection, after a transient, temporary phase of parasitaemia, the parasite disperses to different tissues in an unknown distribution pattern. This study describes the distribution of the parasite after infection by artificial insemination (AI) or blood transfusion. Mares (N = 4) were artificially inseminated with T. equiperdum spiked semen wherea...
Ren WX, Zhang XX, Long CY, Zhao Q, Cheng T, Ma JG, Xu P, Hou G, Ni HB.Horse meat and milk are an important source of nutrition for many Chinese. Previous studies have shown a fairly high prevalence of infection in horses. However, there is no data concerning the molecular characterization of in horses in China. The present study tested 231 cervical lymph node samples of horses from northern China (97 from Jilin, 54 from Liaoning, and 80 from Xinjiang) for the presence of the B1 gene by seminested PCR. The B1-positive samples were genotyped at nine nuclear loci, that is, SAG1, alternative SAG2, SAG3, BTUB, c22-8, GRA6, c29-2, PK1, and an apicoplast locus, usin...
Yan L, Zhang M, Tang L, Ente M, Ma X, Chu H, Li K, Hu D, Zhang D.Myiasis has great economic and medical importance. However, myiasis in wildlife that is caused by oestroid flies is relatively rarely recorded compared with that in humans and domestic animals. Recently, during our research on the conservation of Przewalski's horse (PH), we observed two new records of oestroid flies parasitizing wildlife in China. The first is the horse nasal bot fly, Rhinoestrus sp. (Diptera: Oestridae), found in a dead PH from Kalamaili Nature Reserve. One morphotype (R. purpureus-like) was identified. The second is the Wohlfahrt's wound myiasis fly, Wohlfahrtia magnifica (S...
Leathwick DM, Sauermann CW, Reinemeyer CR, Nielsen MK.A model was developed to reproduce the dynamics of the parasitic stages of equine cyathostomins. Based on a detailed review of published literature, a deterministic simulation model was constructed using the escalator boxcar-train approach, which allows for fully-overlapping cohorts of worms and approximately normally distributed variations in age/size classes. Key biological features include a declining establishment of ingested infective stage larvae as horses age. Development rates are constant for all the parasitic stages except the encysted early third stage larvae, for which development ...
Rissanen K, Galat M, Kovalenko G, Rodnina O, Mikharovskyi G, Must K, Jokelainen P.Horses are recognized as important hosts for the zoonotic parasite Toxoplasma gondii, mainly because meat of infected horses can be a source of human T. gondii infections. However, the baseline knowledge on equine T. gondii infections is limited and lacking from many countries. This seroepidemiological study was set in Ukraine, a country where little is known about T. gondii prevalence in any host species. Methods: We investigated 78 serum samples from horses, collected from Kyiv and Lviv regions of Ukraine, using a commercial enzyme-linked immunosorbent assay (ELISA) and a commercial modified...
McCraw BM, Slocombe JO.Pony foals inoculated with infective Strongylus edentatus larvae were monitored for clinical signs and selected blood changes and were examined at necropsy from two to 56 days postinfection. Larvae penetrated the intestine and reached the liver intravenously before 40 hours postinfection. Occasional thrombi and larval tracks associated with the intima of cecal and colic veins suggested aberrant paths. Larvae in the liver doubled in width between seven and 15 days postinfection and a sudden increment in circulating eosinophils occurred between 11 and 15 days. These changes were probably associa...
Fogarty U, del Piero F, Purnell RE, Mosurski KR.The intestinal tracts of 363 horses were examined after slaughter at a horse abattoir. The presence or absence of Anoplocephala perfoliata and the sites of attachment were recorded. A total of 51 per cent of the horses had A perfoliata attached to the mucosa of the ileocaecal junction and/or to the caecal mucosa; 5 per cent of the horses had A perfoliata attached only to the mucosa of the ileocaecal junction, 24 per cent had A perfoliata attached only to the caecal mucosa and 22 per cent of the horses had A perfoliata attached at both sites. The degree of infestation did not appear to be influ...
Kjaer LN, Lungholt MM, Nielsen MK, Olsen SN, Maddox-Hyttel C.Increased knowledge is needed to assist in the interpretation of presently available diagnostic techniques for infection by the tapeworm Anoplocephala perfoliata in horses. Objective: The suggested cut-off level of an A. perfoliata specific ELISA may not adequately reflect the actual infection level. Hence, faecal egg counts may be a more useful diagnostic test for individual horses than previously reported. Methods: Eighty-four horses admitted for slaughter at a Danish abattoir were examined for the presence of A. perfoliata. The number of tapeworms, their stage of development and gross patho...
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 ...
Krecek RC, Reinecke RK, Horak IG.Between 1980 and 1982, the gastrointestinal tracts of 17 horses which had been grazing on mixed grassveld at Potchefstroom and bushveld at Onderstepoort in the province of Transvaal, Republic of South Africa, were examined at necropsy and processed for parasite recovery. The large strongyles and their prevalences were as follows: Strongylus vulgaris and associated lesions (88-94%), Strongylus edentatus (24%), Strongylus equinus (30%), Triodontophorus nipponicus (35%) and Craterostomum acuticaudatum (18%). The seven most prevalent and abundant cyathostomes collected were Cylicostephanus longibu...
Reubel GH, Barlough JE, Madigan JE.We report on the production and characterization of Ehrlichia risticii, the agent of Potomac horse fever (PHF), from snails (Pleuroceridae: Juga spp.) maintained in aquarium culture and compare it genetically to equine strains. Snails were collected from stream waters on a pasture in Siskiyou County, Calif., where PHF is enzootic and were maintained for several weeks in freshwater aquaria in the laboratory. Upon exposure to temperatures above 22 degrees C the snails released trematode cercariae tentatively identified as virgulate cercariae. Fragments of three different genes (genes for 16S rRN...
Shin J, Ahn KS, Suh GH, Kim HJ, Jeong HS, Kim BS, Choi E, Shin SS.Ocular setariases of cattle were reported but those of equine hosts have never been reported in the Republic of Korea (Korea). We found motile worms in the aqueous humor of 15 horses (Equus spp.) from 12 localities in southern parts of Korea between January 2004 and November 2017. After the affected animals were properly restrained under sedation and local anesthesia, 10 ml disposable syringe with a 16-gauge needle was inserted into the anterior chamber of the affected eye to successfully remove the parasites. The male worm that was found in 7 of the cases showed a pair of lateral appendages n...
Lyons ET, Tolliver SC.Critical tests were performed in 2011 in four weanling horses (L-1, L-2, L-29, and L-30) treated with ivermectin paste at 200 μg/kg. They were born in 2011 and raised together on a farm (MC) in Central Kentucky. The horses had not been treated previously with an antiparasitic drug. However, ivermectin had been administered repeatedly to the horse herd for several years and strongyle eggs per gram of feces (EPGs) returned sooner posttreatment than after initial usage. Critical tests in a recent previous study in this horse herd indicated that the reason for the early return of strongyle EPGs a...
Upjohn MM, Shipton K, Lerotholi T, Attwood G, Verheyen KL.This study aimed to (1) estimate infection prevalence of strongyle, Oxyuris equi and Parascaris equorum species and the intensity of infection with strongyles in working horses in lowland Lesotho and (2) investigate associations between infection and horse age, sex and owner-reported use of anthelmintics. In a cross-sectional survey, fresh faecal samples were obtained from 305 randomly selected horses and worm egg counts performed using a validated field laboratory kit. Details of anthelmintic use were collected using a standardised face-to-face owner questionnaire. Infection prevalence estima...
Duncan JL, Bairden K, Abbott EM.The efficacy of five daily treatments with 7.5 mg fenbendazole/kg bodyweight against mucosal cyathostome larvae was evaluated in 20 12- and 24-month-old ponies with naturally acquired cyathostome infections. After three weeks communal grazing on infected pasture and six weeks indoors, one group of 10 ponies were treated. Six weeks later, both groups of ponies were humanely destroyed and their burdens of large intestinal cyathostome worms, including luminal parasites and mucosal larvae, were assessed. In the control animals approximately 7 per cent of the total worm burden was present in the gu...
Becher AM, Mahling M, Nielsen MK, Pfister K.For 9 consecutive months (March-November 2008), faecal samples were collected monthly from 129 horses residing within 40 km of Salzburg, Austria. Samples were analysed quantitatively using a modified McMaster egg counting technique. Whenever a faecal egg count (FEC) result exceeded 250 eggs per gram (EPG), the horse was treated with pyrantel, ivermectin or moxidectin. In 52 of 129 horses (40.3%), no strongyle eggs were ever detected over the course of 9 months. In 39 horses (30.2%), strongyle eggs were detected in at least 1 sample, but the egg count never exceeded 250 EPG. The remaining 38 (2...
Ribeiro MJ, Rosa MH, Bruhn FR, Garcia Ade M, Rocha CM, Guimarães AM.The present study used the indirect fluorescent antibody test (IFAT) to determine the seroprevalence of Sarcocystis neurona, Toxoplasma gondii and Neospora spp., and evaluated the variables associated with these infections among 506 apparently healthy horses, reared in the south of the state of Minas Gerais, Brazil. This study was conducted between April 2012 and October 2013. Among the horses, the true prevalence of S. neurona was 26% (95% CI: 22.0-30.4%), T. gondii 19.9% (95% CI: 15.5-24.8%) and Neospora spp. 23.9% (95% CI: 19.9-28.1%); and among the farms, 88.3% (95% CI: 74.4-91.6%), 71.6% ...
Traversa D, Kuzmina T, Kharchenko VA, Iorio R, Klei TR, Otranto D.This study investigated the genetic variability within Cylicocyclus nassatus (Nematoda, Strongylida, Cyathostominae) collected from different domestic and wild hosts (i.e. horse, donkey, Przewalskii horse, tarpan and Turkmen kulan) and localities in Europe and/or USA. The ribosomal Internal Transcribed Spacer 2 (ITS2) and the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were PCR-amplified and sequences characterized from seventy individual parasitic specimens. While ITS2 displayed 0-0.6% variation rate among all individual adult specimens of C. nassatus examined, 22 different seque...
Two closed horse herds (Old Lot 4 and Field 24), infected since 1966 with Population B small strongyles resistant to thiabendazole (TBZ) and phenothiazine (PTZ), were terminated in February, March, and May, 2005. At necropsy, only the large endoparasites were identified and counted. The number of horses on pasture was 14 (239 days of age to 23 years old) for Old Lot 4 and two (3 to 20 years old) for Field 24. The time of the last antiparasitic treatment, relative to the year (2005) of necropsy, was 26 years for Old Lot 4 and 9 years for Field 24 horses. Gasterophilus intestinalis third instars...
Acosta-Jamett G, Cleaveland S, Cunningham AA, Bronsvoort BM, Craig PS.Cyst echinococcosis (CE) is one of the most important zoonosis in Chile, where studies have focussed mainly in moist southern regions. The present study was conducted to determine the prevalence of cystic echinococcosis (CE) in livestock and humans in the semiarid Coquimbo region in north-central Chile. A review of all surgical cases of CE in humans reported in the Elqui, Limarí and Choapa provinces in Coquimbo region for the period comprising 1995-2006 was obtained. In addition, a retrospective study of CE covering condemnation records from slaughterhouses of these provinces from the same pe...
Misra KK, Roy S, Choudhury A.Trypanosoma (Trypanozoon) evansi is a causative agent of the dreadful mammalian disease trypanosomiasis or 'Surra' and carried as a latent parasite in domestic cattle but occasionally proves fatal when transmitted to horses and camel. Sporadic outbreak of 'Surra' to different animals (beside their natural hosts) reminds that T. evansi may be zoonotic, as their close relative cause sleeping sickness to human being. This haemoflagellate is mechanically transmitted by horse fly and its effect on different host varies depending on certain factors including the effectiveness of transmission by mech...
Scoles GA, Ueti MW.The apicomplexan hemoprotozoan parasite Theileria equi is one of the etiologic agents causing equine piroplasmosis, a disease of equines that is endemic throughout large parts of the world. Before 2009 the United States had been considered to be free of this parasite. Occasional cases had occurred but there was no evidence for endemic vector-borne transmission in the U.S. until a 2009 outbreak in Texas in which Dermacentor variabilis and Amblyomma cajennense were implicated as vectors. Although D. variabilis has previously been shown to be a competent laboratory vector, studies suggested A. ca...
McManus DP, Smyth JD.Extracts of the horse and sheep strains of Echinococcus granulosus and E. multilocularis were compared on the basis of their isoenzyme patterns for 10 enzymes by means of isoelectric focusing in polyacrylamide gels. The enzymes examined were: acid phosphatase, lactate dehydrogenase, malate dehydrogenase, malic enzyme, phosphoglucoseisomerase, isocitrate dehydrogenase, adenylate kinase, aldolase and alpha-glycerophosphate dehydrogenase. Interspecific and intraspecific differences are apparent in the isoenzyme profiles of all the enzymes except adenylate kinase; the pattern and activity of adeny...
Ai S, Zhang Z, Wang X, Zhang Q, Yin W, Duan Z.Protozoans of Entamoeba spp. are globally distributed zoonotic parasites that infect diverse animal hosts and humans. Prevalence and species/genotypes distribution of Entamoeba spp. in domestic animals are not fully investigated on Qinghai-Tibetan Plateau (QTP), an animal husbandry and agriculture region of China. In a survey, 528 fecal samples were collected from 7 species of domestic animals on multiple locations across QTP region and analyzed by PCR and sequencing analysis. The overall prevalence of Entamoeba spp. infection in all examined animals was 97.9 %. Four Entamoeba species, E. bovi...
Johnson ACB, Biddle AS.Cyathostomins are a multispecies parasite ubiquitous in Equids. Cyathostomins have developed resistance to all but one class of anthelmintics, but species-level sensitivity to anthelmintics has not been shown. This study measured reinfection rates of cyathostomin species following the administration of three commercial dewormers. Nine treated horses were compared with 90 untreated controls during June-September 2017-2019. Ivermectin (IVM) (n = 6), Moxidectin (MOX) (n = 8) or Pyrantel (PYR) (n = 8) were orally administered. Fecal samples were collected every 14 d for 98 d. Fecal egg count reduc...
Veronesi F, Moretta I, Moretti A, Fioretti DP, Genchi C.A study was carried out to assess the field efficacy of ivermectin (IVM) and pyrantel pamoate (PYR) against Parascaris equorum. Seventy-three foals (3-18 months old) from 5 stud farms, not treated with anthelmintics in the previous 10 weeks and with individual faecal egg counts (FEC) >200, were included in the study. For each stud farm, 5-7 foals were included in the IVM-treatment group (IVM 0.2%, 200 mcg/kg body weight) or in the PYR-treatment group (PYR 38%, 13.2mg/kg body weight) and 3 were untreated as controls. For each foal, FECs were carried out before treatment (Day 0) and on Days 7 an...
Williamson RM, Beveridge I, Gasser RB.To compare the sensitivities of three coprological techniques for the diagnosis of Anoplocephala perfoliata infection in horses and to assess the value of the methods for diagnosis of horses at risk of clinical cestodiasis. Methods: Faecal samples were collected from necropsied horses with or without A perfoliata infection and examined using one sedimentation and two different flotation methods. The coprological results were compared with worm counts performed at necropsy of the horses and the degree of mucosal damage. In addition, the efficiency of recovery of A perfoliata eggs from faeces wa...
Gokbulut C, Cirak VY, Senlik B, Aksit D, Durmaz M, McKellar QA.Pour-on formulations of endectocides decrease the risk of injury for both user and animal, and are particularly convenient for animal owners who can apply the product. This study was designed to investigate the plasma disposition and efficacy of ivermectin (IVM) following pour-on, per os and intravenous administrations. Eighteen female horses weighing 510-610 kg were used in this study. The animals were allocated into three groups (per os, pour-on and intravenous groups). The equine paste, bovine pour-on and bovine injectable formulations of IVM were administered orally, topically and intraven...
Hussain N, Shabbir RMK, Ahmed H, Afzal MS, Ullah S, Ali A, Irum S, Naqvi SK, Yin J, Cao J.Ticks are ectoparasites that act as vectors for transmission of various pathogens to wild and domesticated animals and pose a serious threat to human health. Because of the hot and humid conditions in different agro-ecological zones of Pakistan, ticks are abundant and parasitize a variety of animals. The aim of this study was to identify different tick species and distribution on different hosts especially livestock, such as sheep, goat, cattle, buffalo, and camel, and livestock associated canines and equines, such as horse, donkey, and dog, across different agro-ecological zones of Pakistan. ...
Taylor MA, Hunt KR.The term 'anthelmintic drug resistance' describes the heritable ability of some nematode parasites to survive treatment with anthelmintic drugs at the recommended therapeutic dose levels. Genes for resistance appear to be present in many of the important pathogenic nematodes of ruminants and horses. Under intensive management systems, where heavy reliance is placed on anthelmintic drugs for worm control, the selection of resistant genotypes may result in increased reports of the drugs failing to control the nematode populations against which they are aimed. Anthelmintic resistance has been rep...
Cantón GJ, Navarro MA, Asin J, Chu P, Henderson EE, Mete A, Uzal FA.Reproductive failure represents an important cause of economic loss for the equine industry. We reviewed the cases of equine abortion and stillbirth submitted to the California Animal Health and Food Safety Laboratory System, University of California-Davis from 1990 to 2022. A total of 1,774 cases were reviewed. A confirmed cause of abortion was determined in 29.2% of the cases. Abortion or stillbirth was attributed to infectious agents in 18.7% of the cases, with Streptococcus spp., equine herpesvirus 1, and Leptospira spp. being the most prevalent. Noninfectious causes of abortion were estab...
Gondim LSQ, Jesus RF, Ribeiro-Andrade M, Silva JCR, Siqueira DB, Marvulo MFV, Aléssio FM, Mauffrey JF, Julião FS, Savani ESMM, Soares RM, Gondim LFP.Sarcocystis neurona and Neospora spp. are protozoan parasites that induce neurological diseases in horses and other animal species. Opossums (Didelphis albiventris and Didelphis virginiana) are definitive hosts of S. neurona, which is the major cause of equine protozoal myeloencephalitis (EPM). Neospora caninum causes abortion in cattle and infects a wide range of animal species, while N. hughesi is known to induce neurologic disease in equids. The aims of this study were to investigate S. neurona and N. caninum in tissues from opossums in the northeastern Brazil, and to isolate Brazilian stra...
Zakari FO, Ayo JO, Rekwot PI, Kawu MU.The review examines the role of blood in homeostasis, diagnosis and treatment of disease as influenced by meteorological stress factors, age, sex and physical activity of the donkeys. Haematological parameters play a crucial role in clinical diagnosis of infectious and parasitic diseases, in assessing the responses of donkeys to treatment and in prevention of diseases. The changes in blood values are important in evaluating the responses of the animals to various physiologic conditions. In conclusion, haematological values of donkeys are largely influenced by age, sex, physical factors of the ...
Li XM, Geng HL, Wei YJ, Yan WL, Liu J, Wei XY, Zhang M, Wang XY, Zhang XX, Liu G.Cryptosporidiosis is a zoonotic disease caused by Cryptosporidium infection with the main symptom of diarrhea. The present study performed a metaanalysis to determine the global prevalence of Cryptosporidium in Equus animals. Unassigned: Data collection was carried out using Chinese National Knowledge Infrastructure (CNKI), VIP Chinese journal database (VIP), WanFang Data, PubMed, and ScienceDirect databases, with 35 articles published before 2021 being included in this systematic analysis. This study analyzed the research data through subgroup analysis and univariate regression analysis to re...
Mignon B, Losson B.This is the first documented case report of dermatitis associated with the poultry mite (Dermanyssus gallinae) in a horse. It occurred in a 16-year-old horse that was in contact with domestic hens. Clinical signs consisted of severe pruritus, with self-induced hair loss mainly on the head. Despite the multiple skin scrapings performed during both day- and nighttime, mites were only isolated from the in-contact poultry and from the horse's environment, and not the horse. The animal was treated using a 2% permethrin solution, sprayed on the entire body once a week for 4 weeks, and by decontamina...
