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.
Traversa D, Milillo P, Barnes H, von Samson-Himmelstjerna G, Schurmann S, Demeler J, Otranto D, Lia RP, Perrucci S, Frangipane di Regalbono A....A broad scale study was carried out in 2008 to evaluate the distribution and species-specific occurrence of cyathostomin populations in horse yards from Europe. In total 102 properties and 3123 horses were included in Italy (60 yards and 1646 animals), United Kingdom (22 yards and 737 animals) and Germany (20 yards and 740 animals). Individual faecal samples were examined with a McMaster technique while pooled samples were subjected to the microscopic examination of in vitro cultured larvae and to a Reverse Line Blot (RLB) assay able to molecularly identify the most diffused 13 species of cyat...
Wobeser BK, Godson DL, Rejmanek D, Dowling P.A protozoal parasite identified as Neospora hughesi was found in inflammatory lesions in the central nervous system of a Canadian-born adult horse presented with neurological signs. This is believed to be the first case of equine protozoal myeloencephalitis (EPM) caused by Neospora hughesi in a horse outside of the United States. Un parasite protozoaire identifié comme a été trouvé dans les lésions inflammatoires du système nerveux central d’un cheval adulte né au Canada présentant des signes neurologiques. On croit qu’il s’agit du premier cas d’encéphalomyélite protozoai...
Tamarit A, Gutierrez C, Arroyo R, Jimenez V, Zagalá G, Bosch I, Sirvent J, Alberola J, Alonso I, Caballero C.An outbreak of Trypanosoma evansi infection that occurred in mainland Spain is described. The outbreak occurred on an equine and camel farm to which dromedary camels from an infected area of the Canary Islands had recently been introduced. One of these camels developed clinical signs and T. evansi was discovered in a blood smear examination. The herd was evaluated in order to determine the extent of the disease. The results showed that 76% of the camels, 35% of the donkeys and 2% of the horses were affected. The animals were isolated and treated using Cymelarsan((R)) (0.5mg/kg). After treatmen...
Grinberg A, Pomroy WE, Carslake HB, Shi Y, Gibson IR, Drayton BM.To assess the occurrence of Cryptosporidium oocysts in faecal specimens from foals, and investigate an outbreak of neonatal cryptosporidiosis in foals revealed in the course of the study. Methods: Faecal specimens from foals received by a diagnostic veterinary laboratory in New Zealand between 2006 and 2007 were submitted to Massey University and tested microscopically for the presence of Cryptosporidium oocysts. The Cryptosporidium isolates in the oocyst-positive specimens were genetically identified to species level. In addition, specimen submission data from the participating laboratory for...
Santín M, Vecino JA, Fayer R.This is the first report of Enterocytozoon bieneusi in an equid species. Feces from 195 horses from 4 locations in Colombia were examined for E. bieneusi by polymerase chain reaction. Of these, 21 horses (10.8%) were found positive for E. bieneusi . The prevalence of E. bieneusi in horses 1 yr of age (2.5%). No significant differences in prevalence were observed between male (13.7%) and female horses (9%). Sequencing of the internal transcribed spacer region of the SSUrRNA locus identified 3 genotypes. Two genotypes appear to be unique to horses and were named Horse 1 and Horse 2. A third geno...
Nielsen MK, Vidyashankar AN, Andersen UV, Delisi K, Pilegaard K, Kaplan RM.Fecal analyses are becoming increasingly important for equine establishments as a means of parasite surveillance and detection of anthelmintic resistance. Although several studies have evaluated various egg counting techniques, little is known about the quantitative effects of pre-analytic factors such as collection and storage of fecal samples. This study evaluated the effects of storage temperature, storage time and airtight versus open-air storage on fecal egg counts. The experimental protocols were replicated in two study locations: Copenhagen, Denmark and Athens, Georgia, USA. In both loc...
Milillo P, Boeckh A, Cobb R, Otranto D, Lia RP, Perrucci S, di Regalbono AF, Beraldo P, von Samson-Himmelstjerna G, Demeler J, Bartolini R, Traversa D.In the framework of a trial carried out in 2008 in Europe to evaluate the efficacy of major parasiticides against horse cyathostomins, pre- and/or post-treatment Faecal Egg Counts (FEC) were evaluated in a total of 84 yards and 2105 horses from nine different regions from the South, the Center, the North-Center and North-East of Italy. Specifically, on the basis of FECs of the horses present in each property, 60 out of the 84 yards were enrolled for a Faecal Egg Count Reduction Test (FECRT) using fenbendazole, pyrantel, ivermectin and moxidectin. Results: Of the 1646 horses bred in the 60 recr...
Corning S.The small strongyles of horses, also known as cyathostomins, are considered the most prevalent and pathogenic parasites of horses today. The clinical syndrome of larval cyathostominosis which occurs as a result of mass emergence of inhibited stages has a high fatality rate despite the best standard of care given to affected horses. Management of the challenge level of cyathostomins to prevent the syndrome is preferable. Many different management programmes have been tried over the past two decades, with mixed success. Programmes have relied heavily on repeated use of anthelmintic treatments th...
von Samson-Himmelstjerna G, Traversa D, Demeler J, Rohn K, Milillo P, Schurmann S, Lia R, Perrucci S, di Regalbono AF, Beraldo P, Barnes H, Cobb R....For the control of worm infections, the strategic use of anthelmintics, often accompanied by additional farm and/or pasture management procedures, is currently applied on most horse farms in industrialized countries. However, the particular effects of the specific worm control procedures are often unclear and have only been investigated to a limited extent. We examined faecal egg count (FEC), faecal egg count reduction (FECR) and questionnaire data on farm and pasture management procedures. The aim of this study was to determine whether specific worm control practices reported to be applied in...
Lake SL, Matthews JB, Kaplan RM, Hodgkinson JE.Genetic resistance against benzimidazole (BZ) anthelmintics is widespread in cyathostomins, the commonest group of intestinal parasitic nematodes of horses. Studies of BZ-resistant nematodes of sheep, particularly Haemonchus contortus, have indicated that an anthelmintic resistance-conferring T/A polymorphism, encoding an F (phenylalanine) to Y (tyrosine) substitution, in beta-tubulin isotype 1 is present at two loci, codons 167 and 200 (F167Y, F200Y). Recent studies using complementary (c) DNA derived from BZ-susceptible and -resistant cyathostomins identified statistical differences in the f...
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...
Cobb R, Boeckh A.This article reviews the current knowledge of the use of moxidectin (MOX) in horses, including its mode of action, pharmacokinetic and pharmacodynamic properties, efficacy, safety and resistance profile.Moxidectin is a second generation macrocyclic lactone (ML) with potent endectocide activity. It is used for parasite control in horses in an oral gel formulation. The principal mode of action of MOX and of other MLs is binding to gamma-aminobutyric (GABA) and glutamate-gated chloride channels. Moxidectin is different from other MLs in that it is a poor substrate for P-glycoproteins (P-gps) and ...
Traversa D, von Samson-Himmelstjerna G, Demeler J, Milillo P, Schürmann S, Barnes H, Otranto D, Perrucci S, di Regalbono AF, Beraldo P, Boeckh A....A large survey was carried out in 2008 in Europe to evaluate the efficacy of fenbendazole (FBZ), pyrantel (PYR), ivermectin (IVM) and moxidectin (MOX), i.e. the major anthelmintic molecules used in current practice against cyathostomins affecting horses. A total of 102 yards and 1704 horses was studied in three countries: 60 yards and 988 horses from Italy, 22 and 396 from the UK, 20 and 320 from Germany. The survey consisted of Faecal Egg Count Reduction Tests (FECRTs) with a faecal egg count reduction (FECR) categorization of (I) resistance present if FECR <90% and the lower 95% confidenc...
Dantas-Torres F.The objective of this article was to discuss some aspects of ticks associated with domestic animals in the State of Pernambuco, northeastern Brazil, based on a literature review and present new data obtained from recent tick collections carried out in this northeastern Brazilian state. From August 2007 to June 2008, 1,405 ticks were collected and five species were identified: Amblyomma cajennense (Fabricius, 1787), Amblyomma ovale Koch, 1844, Dermacentor nitens Neumann, 1897, Rhipicephalus (Boophilus) microplus (Canestrini, 1887), and Rhipicephalus sanguineus (Latreille, 1806). Dogs from urban...
Müller N, Welle M, Lobsiger L, Stoffel MH, Boghenbor KK, Hilbe M, Gottstein B, Frey CF, Geyer C, von Bomhard W.The present report describes a novel etiological agent of cutaneous leishmaniasis in horses that, at least for some cases, sporadically appeared as autochthonous infections in geographically distant regions of Germany and Switzerland. The infection was initially diagnosed upon clinical and immunohistological findings. Subsequent comparative sequence analysis of diagnostic PCR products from the internal transcribed spacer 1 (ITS1) of ssrRNA classified the respective isolates as neither Old World nor New World Leishmania species. However, four isolates subjected to molecular analyses all exhibit...
Frederick J, Giguère S, Sanchez LC.Diarrhea is common in foals but there are no studies investigating the relative prevalence of common infectious agents in a population of hospitalized diarrheic foals. Objective: To determine the frequency of detection of infectious agents in a population of hospitalized foals with diarrhea and to determine if detection of specific pathogens is associated with age, outcome, or clinicopathologic data. Methods: Two hundred and thirty-three foals < or = 10 months of age with diarrhea examined at a referral institution. Methods: Retrospective case series. Each foal was examined for Salmonella s...
Hébert L, Cauchard J, Doligez P, Quitard L, Laugier C, Petry S.There is great concern about the potential pathogen contamination of horse manure compost spread in the same fields horses graze in. To ensure that pathogen destruction occurs, temperatures need to be sufficiently high during composting. Here, we investigated the survival rate of two marker organisms, Rhodococcus equi and Parascaris equorum eggs, exposed to temperatures potentially encountered during horse manure composting. Our results show that the time required to achieve a 1 log10 reduction in R. equi population (D-value) are 17.1 h (+/-1.47) at 45 degrees C, 8.6 h (+/-0.28) at 50 degrees ...
McWilliam HE, Nisbet AJ, Dowdall SM, Hodgkinson JE, Matthews JB.Parasitic nematodes of the group Cyathostominae are an important cause of disease in horses. This group consists of approximately 50 species, all of which have similar life cycles that involve encystment of larval stages in the large intestinal wall. Encysted larvae can persist for months to years and, occasionally, large numbers can accumulate and emerge synchronously to cause severe pathology, resulting in diarrhoea, weight loss, colic and/or oedema. This syndrome, known as larval cyathostominosis, can be fatal in up to 50% of cases, despite treatment. There is no diagnostic method that enab...
Kornaś S, Skalska M, Nowosad B, Gawor J, Kharchenko V, Cabaret J.Three parts of the large intestine, i.e. the dorsal and ventral colon, and caecum in 41 working horses from small farms in southern Poland were examined. Five species of large strongyles (3 migratory species from genus Strongylus and 2 non-migratory from genus Triodontophorus) and as well as 17 species of cyathostomes were revealed. The prevalence of large strongyles was observed, accordingly: Strongylus vulgaris--80.5%, S. equinus--9.8%, S. edentatus--4.9%, Triodontophorus serratus--19.5% and T. brevicauda--7.3%. Among cyathostomes, 5 most prevalent species were Cyathostomum catinatum--31.7%,...
Nizoli LQ, Conceição FR, Silva SS, Dummer LA, Santos AG, Leite FP.The equine piroplasmosis caused by Theileria equi is one of the most important parasitic diseases of the equine, causing damage to animal health and economic losses. In T. equi, 2 merozoite surface proteins, equi merozoite antigen EMA-1 and EMA-2, have been identified as the most immunodominant antigens. This suggests that these antigens might be used as immunobiological tools. The EMA-1 of Theileria equi was cloned and expressed in the yeast Pichia pastoris. The transformed yeast was grown at high cell density, expressing up to 389 mg x L(-1) of recombinant protein. The protein was concentrat...
Gürelli G, Göçmen B.Blepharocorys curvigula Gassovsky, 1919 found in the intestine of domestic horses (Equus caballus Linnaeus, 1758), living in the vicinity of Izmir was investigated. It was seen in nine of the thirteen horses examined (69%). This study reports the presence of Blepharocorys curvigula in the intestine of Equids for the first time in Turkey. Specimens were found to be similar to the original descriptions on the basis of morphological characters and biometric data.
Hamza E, Torsteinsdottir S, Eydal M, Frey CF, Mirkovitch J, Brcic M, Wagner B, Wilson AD, Jungi TW, Marti E.Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides spp. IBH does not occur in Iceland where Culicoides are absent. However, following importation into continental Europe where Culicoides are present, >or=50% of Icelandic horses (1st generation) develop IBH but
Reinemeyer CR, Nielsen MK.Equids are hosts to dozens of species of internal parasites that infect no other domestic animals. Virtually all horses, especially those exposed to pasture, experience some level of parasitism continuously. Despite pathologic evidence of parasitic damage in various organs and tissues, few parasitisms are manifested systemically in well-managed horses. Contrary to conventional wisdom, only three common parasitisms of horses are likely to be manifested as colic: Strongylus vulgaris, Parascaris equorum, and Anoplocephala perfoliata. This article discusses the life cycles, pathophysiology, manife...
Francisco I, Arias M, Cortiñas FJ, Francisco R, Mochales E, Sánchez JA, Uriarte J, Suárez JL, Morrondo P, Sánchez-Andrade R, Díez-Baños P....Two groups of autochthonous Pura Raza Galega (PRG) horses, one comprising 483 animals under a silvopasturing regime, and the other comprising 72 PRG horses managed in farms, were used to analyse the effect of silvopasture on infection by endoparasites. Results were considered according to the age and the sex of the horses. Faecal samples were individually collected from each animal and analysed by the coprological flotation, sedimentation and migration techniques. Coprocultures were also done to identify the main strongylid genera affecting the horses. Eggs from the gastrointestinal nematoda P...
Duffy CW, Morrison LJ, Black A, Pinchbeck GL, Christley RM, Schoenefeld A, Tait A, Turner CM, MacLeod A.African animal trypanosomiasis, or Nagana, is a debilitating and economically costly disease with a major impact on animal health in sub-Saharan Africa. Trypanosoma vivax, one of the principal trypanosome species responsible for the disease, infects a wide host range including cattle, goats, horses and donkeys and is transmitted both cyclically by tsetse flies and mechanically by other biting flies, resulting in a distribution covering large swathes of South America and much of sub-Saharan Africa. While there is evidence for mating in some of the related trypanosome species, Trypanosoma brucei...
Sanada Y, Senba H, Mochizuki R, Arakaki H, Gotoh T, Fukumoto S, Nagahata H.To establish a reliable diagnostic measure for equine Anoplocephala perfoliata infection, the impact of deworming was examined in 12 Thoroughbreds to which bithionol (5-10 mg/kg body weight) was administered and feces were examined by the modified Wisconsin method using sucrose solution. One day after the administration, cestode eggs were detected in previously fecal egg-negative 3 horses and increased in the other 9 horses. The optimum time for post-deworming egg detection was examined in following horses: 17 mares were administered bithionol and 10 mares were used as controls. The fecal egg ...
Hébert L, Guitton E, Madeline A, Géraud T, Carnicer D, Lakhdar L, Pitel PH, Coste M, Laloy E, Giraudet A, Zientara S, Büscher P, Laugier C, Hans A....Trypanosoma equiperdum, the causative agent of dourine, may affect the central nervous system, leading to neurological signs in infected horses. This location protects the parasite from most (if not all) existing chemotherapies. In this context, the OIE terrestrial code considers dourine as a non-treatable disease and imposes a stamping-out policy for affected animals before a country may achieve its dourine-free status. The use of practices as drastic as euthanasia remains controversial, but the lack of a suitable tool for studying a treatment's efficacy against dourine hampers the developmen...
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...
Bairden K, Brown SR, McGoldrick J, Parker LD, Talty PJ.The efficacy of moxidectin 2 per cent equine gel against naturally acquired strongyle infections was assessed in 18 ponies which had grazed on contaminated pasture before being housed for eight weeks. Twenty-four hours before the treatment, two randomly selected ponies were euthanased and their worm burdens were determined. Eight of the remaining 16 ponies were treated with moxidectin 2 per cent gel while the other eight were given a placebo gel. Eight weeks later the 16 animals were necropsied and their worm burdens established. A 100 per cent efficacy was recorded against adult and lumenal L...
Sabir N, Chaudhry ZI, Aslam A, Muhammad K, Shahid M, Hussain A, Khan SA, Ahmad I.Trypanosomiasis is an important protozoal disease with a diverse range of susceptible host including human. In the current study, molecular characterization of prevalent species was done through a pan-trypanosome polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP). A total of three hundred (n = 300) equines including horses, donkeys and mules (100 each) were randomly selected and the equine blood samples were subjected to screening for trypanosomes through microhaematocrit centrifuge technique (MHCT), conventional PCR, semi-nested PCR and RFLP. Overall...
Kelly JD, Hall CA.This chapter discusses the resistance of animal helminths to anthelmintics. Resistance is defined as a significant increase in the ability of individuals within a strain to tolerate doses of a compound, which would prove lethal to the majority of individuals in a normal population of the same species. The introduction of phenothiazine and the benzimidazole broad-spectrum anthelmintics, has unfortunately led to the selection of drug-resistant strains of important parasitic helminths. The emergence of an increasing number of resistant helminths is associated with the widespread use and misuse of...
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...
Eysker M, Jansen J, Mirck MH.Inhibited early third stage larvae of Cyathostominae were found in the digested mucosa of the large intestine of 12 yearling, female Shetland ponies, which were used in two grazing experiments. The ponies were killed in late autumn. In some ponies the inhibited larvae were very abundant and in most animals the majority of the Cyathostominae populations consisted of these early third stage larvae, suggesting that the phenomenon has an epidemiological significance.
Scare JA, Steuer AE, Shaffer CL, Slusarewicz P, Mousley A, Nielsen MK.In vitro maintenance of helminth parasites enables a variety of molecular, pharmaceutical and immunological analyses. Currently, the nutritional and environmental in vitro requirements of the equine ascarid parasite, Parascaris spp., have not been determined. Additionally, an objective method for assessing viability of Parascaris spp. intestinal stages does not exist. The purpose of this study was to ascertain the in vitro requirements of intestinal stages of Parascaris spp., and to develop a viability assessment method. A total of 1045 worms were maintained in a total of 212 cultures. Worms o...
Seyoum Z, Zewdu A, Dagnachew S, Bogale B.A study was conducted from November 2015 to April 2016 to determine fenbendazole and ivermectin resistance status of intestinal nematodes of cart horses in Gondar, Northwest Ethiopia. Forty-five strongyle infected animals were used for this study. The animals were randomly allocated into three groups (15 horses per group). Group I was treated with fenbendazole and Group II with ivermectin and Group III was left untreated. Faecal samples were collected from each cart horse before and after treatment. Accordingly, the reduction in the mean fecal egg count at fourteen days of treatment for iverme...
Ortega-García MV, Salguero FJ, García N, Domínguez M, Moreno I, Berrocal A.Cutaneous forms of leishmaniosis due to Leishmania braziliensis have been reported in horses in the New World. Domestic animals play a role in the transmission of the disease. In Costa Rica, human cases of L. braziliensis, L. panamensis and L. infantum have been reported. The present report describes five cases of equine cutaneous leishmaniosis in Costa Rica. The aetiological diagnosis was based on the presence of the parasite within the lesions. Skin biopsies were used to perform histopathological analyses of the lesions. Immunohistochemistry was used to detect the presence of the Leishmania ...
Saadi, A, Tavassoli, M, Dalir-Naghadeh, B, Samiei A.Dictyocaulus arnfieldi is a lungworm commonly found in equids; however, relatively little is known about it. The aim of the present study was to establish the prevalence of equine lungworms in naturally-infected working and sporting horses, donkeys and mules in rural areas of Urmia, northwest Iran. The fecal samples were collected from 299 working horses, 57 sporting horses, 66 donkeys and 37 mules during the period March 2014 to June 2016. The collected fecal samples were processed within 48 hours following rectal sampling. The larval count/g (LPG) of feces was determined using the Baermann t...
Wilson AD.Horses are affected by a wide variety of arthropod ectoparasites, ranging from lice which spend their entire life on the host, through ticks which feed over a period of days, to numerous biting insects that only transiently visit the host to feed. The presence of ectoparasites elicits a number of host responses including innate inflammatory responses, adaptive immune reactions and altered behaviour; all of which can reduce the severity of the parasite burden. All of these different responses are linked through immune mechanisms mediated by mast cells and IgE antibodies which have an important ...
Inácio SV, de Brito RL, Zucatto AS, Coelho WM, de Aquino MC, Aguirre Ade A, Perri SH, Meireles MV, Bresciani KD.The present study aimed to analyze the occurrence of infection by Cryptosporidium spp. in mares and their respective foals. This study was carried out in 11 farms located in the municipalities of Araçatuba, Birigui, Guararapes and Santo Antônio do Aracangua, in the northwest region of the State of Sao Paulo, from November 2010 to March 2011. A total of 98 mares and 98 foals of several breeds were analyzed; among foals, 59 were males and 39 females, aged from three to 330 days. Feces were collected directly from the rectal ampulla, purified and processed according to modified Kinyoun stain. O...
Singh G, Singh NK, Singh H, Rath SS.A total of 311 equine faecal samples (190 horses and 121 mules) collected from six districts of Central Plain Zone, Punjab were examined using standard coprological methods. The results showed an overall prevalence of 27.33 % for strongyles with rare to mild type of infection as evident from egg per gram of faeces. In particular, amongst the examined samples, 17.90 % of horses and 42.14 % of mules were infected and the difference was statistically significant (P < 0.01). Identification of the faecal culture harvested larval stages, showed 56 % and 46 % of horses and mules, respectively, ...
Richards KS, Riley EM, Taylor DH, Morris DL.Protoscoleces of Echinococcus granulosus were subjected to high concentrations of praziquantel (10-1000 micrograms/ml medium or cyst fluid) for a short, 10 min duration in vitro or in situ within cysts. Drug efficacy was then monitored either by in vitro culture in drug-free medium and/or by passage into rodents. The in vitro test of effectiveness suggested that ovine-derived protoscoleces were more sensitive than those of equine origin, and that the in vitro method of treatment was more successful than that performed in situ. However, the subsequent passage of treated protoscoleces, whether i...
Saes IL, Vera JHS, Fachiolli DF, Yamada PH, Dellaqua JVT, Saes RL, Amarante AFT, Soutello RVG.The aim of this study was to determine the time required by different anthelmintic agents to reduce strongyle egg shedding in horses. Fifty horses were divided into five homogenous groups based on faecal egg counts (FECs). Treatment groups received either ivermectin; moxidectin; fenbendazole; piperazine; or no treatment (control group). Faecal examinations were performed 4, 8, 12, 18, 24, 36 and 48h after the anthelmintic treatment. After this period, faecal samples were taken every 24h over the next 12days and finally on alternate days (48-h intervals) for another 14days until the end of the ...
Farkas R, Hall MJ.Veterinarians in Hungary were asked to complete a questionnaire on traumatic myiasis; of the 664 veterinarians contacted, 247 replied (37.2 per cent) and of these 209 (84.6 per cent) reported myiasis to be a problem among the livestock they treated. Infestation levels of > 10 per cent of animals were reported in sheep, cattle and horses. The myiasis season lasted from March to November with most cases reported in July and August. Significantly more respondents reported that fly larvae were present deep in wounds rather than superficially, consistent with infestations due to the obligate parasi...
Foil LD, Klei TR, Miller RI, Church GE, Foil CS, French DD, Smith JN.Seasonal changes in density and spatial distribution of Onchocerca cervicalis microfilariae were studied in ventral-midline skin of 15 infected pony mares in southern Louisiana. Triple running mean analysis of data over a 13-mo period indicated that a distinct pattern exists in total microfilariae population density and in microfilariae occurrence in different levels of the dermis. Microfilariae density reaches peak levels in the spring followed by a 58% decrease in the summer, a 19% increase in the fall, and a decrease to the lowest numbers in the winter. Microfilariae were found in all level...
Polley L.In an abattoir survey of 383 horses from the four western provinces of Canada and 240 horses from Washington, Montana and North Dakota prevalences of Onchocerca sp of 11.8% and 25.8% respectively have been demonstrated by umbilical skin specimen examinations. The results of this survey are discussed in relation to the parasite's natural history and its clinical significance in western Canada.
Yeargan MR, Howe DK.Equine protozoal myeloencephalitis (EPM) is a common neurologic disease of horses that is caused by the apicomplexan pathogen Sarcocystis neurona. To help improve serologic diagnosis of S. neurona infection, we have modified existing enzyme-linked immunosorbent assays (ELISAs) based on the immunogenic parasite surface antigens SnSAG2, SnSAG3, and SnSAG4 to make the assays polyvalent, thereby circumventing difficulties associated with parasite antigenic variants and diversity in equine immune responses. Two approaches were utilized to achieve polyvalence: (1) mixtures of the individual recombin...
Anis E, Ilha MRS, Engiles JB, Wilkes RP.Equine infectious disease outbreaks may have profound economic impact, resulting in losses of millions of dollars of revenue as a result of horse loss, quarantine, and cancelled events. Early and accurate diagnosis is essential to limit the spread of infectious diseases. However, laboratory detection of infectious agents, especially the simultaneous detection of multiple agents, can be challenging to the clinician and diagnostic laboratory. Next-generation sequencing (NGS), which allows millions of DNA templates to be sequenced simultaneously in a single reaction, is an ideal technology for co...
Böse R, Peymann B.From Babesia caballi in vitro cultures a preparation of 100% infected erythrocytes was obtained. From this, B. caballi antigens were extracted with the detergent 3-[(3-Cholamidopropyl)-dimethylammonio]-1-propane-sulfonate (CHAPS) and used as ELISA antigens. A control antigen of normal erythrocytes from the same donor horse was prepared in an identical manner. The ELISA and Western blot were validated by testing of sera from horses experimentally infected with B. caballi or B. equi or not infected with Babesia spp. ELISA and Western blot results were compared with those obtained by the immunofl...
Locatelli-Dittrich R, Dittrich JR, Richartz RR, Gasino Joineau ME, Antunes J, Pinckney RD, Deconto I, Hoffmann DC, Thomaz-Soccol V.Antibodies to Neospora sp. and Toxoplasma gondii were measured in mares and precolostral foals from a farm in Parana State, Brazil. An indirect fluorescent antibody test (IFAT) was used to determine specific antibodies. Three sampling points, 2003, 2004 and at parturition were included in the study, but not all horses are represented at a parturition time point. In 2003, antibodies to Neospora were detected in 17 mares (47%) at 1:50 dilution and in 5 mares (13.8%) at 1:100 dilution. In 2004, antibodies to Neospora were found in 11/36 (30%) horses with titers of 1:50 and in 6 mares (16.6%) at 1...
Breider MA, Kiely RG, Edwards JF.A generalized debilitating disease in a horse was believed to be related to hypersensitivity to migrating strongyle larvae. The clinical signs included weight loss, diarrhea, and ulcers on all 4 coronary bands. The mare's condition deteriorated rapidly, so the mare was euthanatized and necropsied. The major histopathologic findings were chronic multifocal eosinophilic pancreatitis, hepatic portal fibrosis, biliary hyperplasia, and chronic ulcerative eosinophilic colitis. This case was similar to previously reported cases of chronic eosinophilic gastroenteritis in horses. Although the etiologic...
Equine piroplasmosis (EP) is an endemic tick-borne disease found in most countries around the world. It affects all species of Equidae, and it is caused by Theileria equi, Babesia caballi and T. haneyi. The research herein is the second study on the prevalence of piroplasms in Romania conducted in the past two decades. The aim of this study was to assess the seroprevalence of anti-Theileria equi antibodies and the geographical distribution of this disease in the southwest, west, and northwest regions of Romania in order to obtain a more thorough understanding of the parasitological status of h...
Marques C, da Silva B, Nogueira Y, Bezerra T, Tavares A, Borges-Silva W, Gondim L.The protozoan (syn. ) infects horses and has dogs as definitive hosts. Herein we aimed to detect in Brazilian horses destined for human consumption and to determine the frequency of infection in the examined animals. Muscle fragments from 51 horses were collected in a slaughterhouse in Bahia State during three different seasons of the year. Samples from six tissues from each animal were prepared for macroscopic and microscopic evaluation, using tissue grinding, squash and histology. sp. was observed in 100% of the examined horses. Selected samples were processed for transmission electron mi...
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...
Sumbria D, Singla LD, Sharma A, Bal MS, Kumar S.Multiplex PCR for simultaneous detection of Trypanosoma evansi and Theileria equi in single-step reaction was optimized and employed on 108 equids (99 horses and 9 donkeys/mules) blood samples collected from two agro-climatic zones (Sub-mountain undulating zone and Undulating plain zone) of Punjab to evaluate the status of concurrent infection and associated risk factors. The amplification products of 257 and 709 bp targeting repetitive nucleotide sequence of variable surface glycoproteins of T. evansi and 18S rRNA gene of T. equi, respectively expressed high fidelity of the primer pairs with ...
Drudge JH, Lyons ET, Tolliver SC.Three formulations of cambendazole were evaluated for anthelmintic activity by critical testing method in 21 horses. Cambendazole suspension was administered via stomach tube at the dose rate of 10 mg/kg to 3 horses and at the dose rate of 20 mg/kg to 3 horses. Cambendazole paste was given intraorally to 8 horses, and the pellet formulation was fed to 7 horses at the dose rate of 20 mg/kg. Anthelmintic activity of cambendazole was similar for all dose rates and formulations. Gasterophilus intestinalis, Gasterophilus nasalis, Draschia megastoma, Anoplocephala perfoliata, and Anoplocephala magna...