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.
Wilkołek PM, Pomorski ZJ, Szczepanik MP, Adamek L, Pluta M, Taszkun I, Gołyński M, Rozwód A, Sitkowski W.The present study was designed to asses specific IgE towards environment allergens in 42 healthy horses. Determination of this immunoglobulin in serum serve as diagnostic tools in allergic diseases to improve efficacy of the treatment and proper allergen selection to specific immunotherapy. Serum levels of allergen specific IgE were measured with equine monoclonal antibody, using 15 individual and 5 mix allergens in North European Panel. The study revealed season dependent increased levels of allergen specific IgE in normal horses. It is noteworthy that healthy horses show high percentage of p...
Michlik KM, Biazik AK, Henklewski RZ, Szmigielska MA, Nicpoń JM, Pasławska U.Quadricuspid aortic valve (QAV) and ventricular septal defect (VSD) are congenital heart defects and have been described in both human and veterinary medical literature. Methods: A 5-year-old half-bred bay stallion was referred for surgical castration. Cardiac murmurs were heard on the presurgical clinical examination and the cardiac examination revealed subcutaneous oedema, tachycardia with a precodrial thrill and a grade 5/6 pansystolic murmur, which was heard on auscultation of the right and left side of the chest. Examination of the B-mode echocardiograms revealed the presence of a QAV (on...
Guo PF, Chen TT, Tsaihong JC, Ho GD, Cheng PC, Tseng YC, Peng SY.Cryptosporidiosis is a zoonotic disease caused by the protozoan parasite Cryptosporidium. A total of 436 horse fecal samples were collected from 19 farms, and acid-fast staining method was used for primary screening. Cryptosporidium oocysts were found in 161 samples, among which 33 positive sample were selected for nested PCR, restriction fragment length polymorphism analysis and DNA sequencing of 18 S rDNA, showing 31 samples to be bovine C. parvum and 2 C. felis. The methods employed in this study should be useful as tools to identify cryptosporidiosis genotypes and species of livestock.
Morsy AT, Saleh MS, Morsy TA.A zoonosis is an animal disease that is transmissible to humans. Humans are usually an accidental host that acquires disease through close contact with an infected animal, who may or may not be symptomatic. Children are at highest risk for infection because they are more likely to have close contact with pets. Pets are responsible for transmission of an extensive array of bacterial, fungal, and parasitic zoonotic pathogens. The route of transmission can be through the saliva (e.g., bites or contaminated scratches), feces, respiratory secretions, direct contact, or by the animal acting as a veh...
Qingling M, Guanglei W, Jun Q, Xinquan Z, Tianli L, Xuemei S, Jinsheng Z, Huisheng W, Kuojun C, Chuangfu C.Hydatid worms, hosted by humans and animals, impose serious human health risk and cause significant livestock production loss. To better understand the disease infection status in Xinjiang, China, we investigated the disease epidemics in 4 livestock animals, i.e., cattle, sheep (both sheep and goat), camels, and horses, slaughtered at the abattoirs in Urumqi, Yining, Tacheng, and Altay areas. The results showed that the animals were infected at different rates, in the order of sheep (9.8%), cattle (8.4%), camels (6.8%), and horses (4.3%). The infection rates were found to be different between ...
Sumbria D, Singla LD, Sharma A, Moudgil AD, Bal MS.The detection of Trypanosoma evansi in blood is intricate, primarily in chronic stage of infection, as the parasitaemia is often low and fluctuating. The climatic conditions of the target area of Punjab (a province of India with a total of 34,000 horses and ponies used for sports and transport) are conducive for the parasite propagation. The objective of present investigation was to assess the prevalence of T. evansi in central and western Punjab by PCR and card agglutination test (CATT/T. evansi) in relation to clinico-haematobiochemical alterations and risk factors associated with latent try...
Acosta Ida C, Da Costa AP, Gennari SM, Marcili A.Trypanosoma and Leishmania infections affect wild and domestic animals and human populations. The growing process of deforestation and urbanization of Atlantic Rainforest areas has given rise to introduction of humans and domestic animals to the sylvatic cycles of Trypanosoma and Leishmania species. Serological, parasitological, and molecular surveys among wild and domestic animals in the Corrego do Veado Biological Reserve, which is an Atlantic Rainforest fragment in the state of Espírito Santo, southeastern Brazil, were evaluated. In total, 154 wild animals of 25 species and 67 domestic ani...
Collas C, Fleurance G, Cabaret J, Martin-Rosset W, Wimel L, Cortet J, Dumont B.Agroecology opens up new perspectives for the design of sustainable farming systems by using the stimulation of natural processes to reduce the inputs needed for production. In horse farming systems, the challenge is to maximize the proportion of forages in the diet, and to develop alternatives to synthetic chemical drugs for controlling gastrointestinal nematodes. Lactating saddle mares, with high nutritional requirements, are commonly supplemented with concentrates at pasture, although the influence of energy supplementation on voluntary intake, performance and immune response against parasi...
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 ...
Reinemeyer CR, Prado JC, Andersen UV, Nielsen MK, Schricker B, Kennedy T.Strongylid infections are ubiquitous in grazing horse populations. Infections with cyathostomin (small strongyle) and strongylin (large strongyle) nematodes have long been associated with clinical disease in horses, but little is known about their subclinical impact. A masked, randomized, controlled study was conducted to evaluate the effects of daily administration of pyrantel tartrate on body condition scores, weight gain, fecal egg counts, and total worm counts of young horses repeatedly inoculated with strongylid larvae. Twenty eight immature horses were treated with larvicidal anthelminti...
Betancourt A, Lyons ET, Horohov DW.Anthelmintic treatments have been associated with local inflammatory reactions. Since each class of anthelmintic has unique mechanisms of action affecting different subpopulations of parasites, we hypothesised that they will also induce characteristic proinflammatory responses. Objective: To determine the effect of anthelmintic class on the proinflammatory response post treatment. Methods: Ponies naturally infected with cyathostomins and other parasites after pasture grazing were left untreated or treated with representatives of 3 different classes of anthelmintics: fenbendazole (benzimidazole...
Schurer J, Davenport L, Wagner B, Jenkins E.Fecal samples from wild and domestic carnivores are routinely frozen for three days at -80°C to kill eggs of Echinococcus spp., following recommendations from the World Health Organization (WHO) and World Organization for Animal Health (OIE). This is done to decrease the risk of zoonotic infection with these pathogenic cestodes. In addition, it is often necessary to freeze fecal samples collected for research prior to batch processing by a limited number of personnel, especially large numbers of samples or those collected in remote locations. The effect of freezing on the recovery of endopara...
Bohórquez A, Meana A, Pato NF, Luzón M.Current copro-diagnostic tests for Anoplocephala perfoliata show high variation in their sensitivity and given the morphological similarity of Anoplocephala spp. eggs, this could be related to the presence of Anoplocephala magna alone or co-existing with A. perfoliata. In the present study, coprology was significantly more sensitive (p<0.01) at detecting A. magna than A. perfoliata. This difference was independent of the parasite burden and was greater when testing was limited to horses with mature or gravid tapeworms. A. magna infection was strongly linked to young horses (≤ 2 years). The e...
Tomczuk K, Kostro K, Szczepaniak KO, Grzybek M, Studzińska M, Demkowska-Kutrzepa M, Roczeń-Karczmarz M.The autopsy of 487 slaughter horses revealed the presence of Anoplocephala perfoliata in 36 animals. The invasions varied in the intensity (3 to 2,069 tapeworms) and in the level of tapeworms' proglottid maturity. Twenty nine horses were found to contain tapeworms with gravid proglottid. Fecal samples collected from the rectum were tested using following techniques: flotation with solution-saturated NaCl, decantation, McMaster's, and modified sedimentation-flotation methods (50 g feces samples, flotation solution-saturated NaCl and sucrose, specific gravity 1.25 g/ml). The number of A. perfoli...
Geurden T, van Doorn D, Claerebout E, Kooyman F, De Keersmaecker S, Vercruysse J, Besognet B, Vanimisetti B, di Regalbono AF, Beraldo P, Di Cesare A....The objective of the present study was to evaluate the efficacy of an oral treatment with ivermectin (IVM) or moxidectin (MOX) against gastro-intestinal strongyles in naturally infected horses by performing a faecal egg count reduction test (FECRT) and by monitoring the egg reappearance period (ERP) after treatment. Therefore, a field efficacy study with a randomised complete block design for each study site was conducted, with the individual animal as the experimental unit. At least 10 study sites in Italy, Belgium and The Netherlands were selected and animals were allocated to one of the two...
Ellse L, Burden FA, Wall R.A longitudinal study was undertaken over a 21 months period to examine the seasonal abundance of lice infesting donkeys, the risk factors which predispose donkeys to infestation and the effectiveness of louse management. All the lice seen were Bovicola (Werneckiella) ocellatus. A strong seasonal pattern, which was correlated with mean monthly temperature, was observed with higher prevalence and intensity in the cooler, winter months (October-March). Overall infestation in these animals was over-dispersed, suggesting that some individuals are strongly predisposed to infestation. Donkey age and ...
Relf VE, Lester HE, Morgan ER, Hodgkinson JE, Matthews JB.Anthelmintic drugs have been applied indiscriminately to control horse nematodes for over 40 years. We undertook a comprehensive study to investigate efficacy of the four available broad-spectrum anthelmintic drugs on 16 Thoroughbred stud farms using the faecal egg count reduction test. Efficacy against strongyles was determined by calculating the percentage of reduction in faecal egg count between the group mean at Day 0 and Days 14-17 post-treatment and the 95% lower confidence intervals estimated by non-parametric bootstrapping. Individual strongyle faecal egg count reduction tests (n=429) ...
Baldacchino F, Desquesnes M, Mihok S, Foil LD, Duvallet G, Jittapalapong S.Tabanids are nuisance pests for people and livestock because of their painful and irritating bite, persistent biting behavior, and blood ingestion. About 4400 tabanid species have been described; they are seasonally present in all kinds of landscapes, latitudes, and altitudes. High populations have a significant economic impact on outdoor activities, tourism, and livestock production. Tabanids are also vectors of animal disease agents, including viruses, bacteria and parasites. However, tabanids have received little attention in comparison with other hematophagous Diptera. Here, we highlight t...
Truppel JH, Otomura F, Teodoro U, Massafera R, da Costa-Ribeiro MC, Catarino CM, Dalagrana L, Costa Ferreira ME, Thomaz-Soccol V.In this study, we detected Leishmania (Viannia) braziliensis infection in equids living in endemic regions of cutaneous leishmaniasis. To determine the role of these animals in the Leishmania cycle, we used two approaches: serological and molecular methods. Antibodies to the parasite were assayed using the Enzyme Linked Immunosorbent Assay (ELISA). Blood samples were collected and tested by polymerase chain reaction (PCR), and the positive products were sequenced. The results showed that 11.0% (25/227) of the equids were seropositive for Leishmania sp, and 16.3% (37/227) were PCR positive. Ant...
Song SD, Barker SC, Shao R.The genus Haematopinus contains 21 species of blood-sucking lice, parasitizing both even-toed ungulates (pigs, cattle, buffalo, antelopes, camels and deer) and odd-toed ungulates (horses, donkeys and zebras). The mitochondrial genomes of the domestic pig louse, Haematopinus suis, and the wild pig louse, Haematopinus apri, have been sequenced recently; both lice have fragmented mitochondrial genomes with 37 genes on nine minichromosomes. To understand whether the composition of mitochondrial minichromosomes and the gene content and gene arrangement of each minichromosome are stable within the g...
Abreu RA, Weiss RR, Thomaz-Soccol V, Locatelli-Dittrich R, Laskoski LM, Bertol MA, Koch MO, Alban SM, Green KT.Sera from 112 mares from 5 horse-breeding farms was examined for the presence of antibodies to Neospora caninum and Toxoplasma gondii by an indirect fluorescent antibody test (IFAT), as well as from dogs and cattle present on these properties for the presence of antibodies to N. caninum. Among the 112 mares, 35 had a history of reproductive problems in the last breeding season and 77 had no reproductive problems. The rates of seroprevalence of N. caninum in mares with and without a history of reproductive problems were 25.71% and 6.49% and from T. gondii 2.85% and 1.29%, respectively. In dogs ...
Nielsen MK, Pfister K, von Samson-Himmelstjerna G.Since the 1960s equine parasite control has relied heavily on frequent anthelmintic treatments often applied with frequent intervals year-round. However, increasing levels of anthelmintic resistance in cyathostomins and Parascaris equorum are now forcing the equine industry to change to a more surveillance-based treatment approach to facilitate a reduction in treatment intensity. The principle of selective therapy has been implemented with success in small ruminant parasite control, and has also found use in horse populations. Typically, egg counts are performed from all individuals in the pop...
Giacominelli-Stuffler R, Frangipane di Regalbono A, Traversa D, Geurden T, Marcer F, Di Francesco A, Angelini C, di Cesare A, Storelli MM....Leukotrienes are products of the arachidonic acid metabolism and act as potent inflammatory mediators modulating the immune response and various physiological processes. This study evaluated the expression and activity of 5-lipoxygenase (5-LOX), the enzyme that catalyzes the first two steps in the biosynthesis of leukotrienes, in horses infected by larval cyathostomins. Tissue samples from dorsal and ventral colon, and from the cecum were collected from 16 horses slaughtered for human consumption. Samples were analyzed to estimate the burdens of encysted cyathostomin larvae and adult luminal s...
Kudrnáčová M, Langrová I, Maršálek M, Jankovská I, Scháňková S, Brožová A, Truněčková J.The occurrence of Hypoderma diana (Diptera: Hypodermatidae) in a herd of 15 horses was observed during a 4-year period (2010-2013) in northwest Bohemia. During this period, infestation by the warble fly H. diana increased from 12.5% in 2010 to 53.3% in 2013. Nodules were observed on the neck, back, stomach, legs, and head. The incidence of H. diana was probably influenced by the presence of a specific host mouflon (Ovis orientalis musimon).
Hertzberg H, Schwarzwald CC, Grimm F, Frey CF, Gottstein B, Gerber V.The epidemiological situation of strongyle infections in adult horses in Switzerland is characterized by a strong dominance of small strongyles (Cyathostominae) and an overall low level of egg shedding in the faeces. The prevailing attitude towards anthelmintic therapy considers neither husbandry conditions nor pasture hygiene measures. Instead, calendar-based routine medication, comprising usually 3 to 4 annual treatments, is the typical strategy. Such an approach, however, often results in an excessive administration of anthelmintics. With respect to the continuous spread of drug resistant c...
Andersen UV, Reinemeyer CR, Toft N, Olsen SN, Jacobsen S, Nielsen MK.Migrating Strongylus vulgaris and encysted cyathostomin larvae cause a localized inflammatory response in horses. It is unknown whether these larvae elicit a systemic acute phase response (APR), evidenced by changes in serum amyloid A (SAA), haptoglobin (Hp), iron (Fe), albumin, or albumin/globulin (A/G) ratio. In this study, 28 horses were randomly allocated to receive either pyrantel tartrate or a pelleted placebo formulation in their daily feed. Concurrent with treatment, all the horses were administered 5000 pyrantel-susceptible cyathostomin infective larvae once daily, 5 days a week, for ...
Corbett CJ, Love S, Moore A, Burden FA, Matthews JB, Denwood MJ.The level of anthelmintic resistance within some cyathostomin parasite populations has increased to the level where sole reliance on anthelmintic-based control protocols is not possible. Management-based nematode control methods, including removal of faeces from pasture, are widely recommended for use in association with a reduction in anthelmintic use to reduce selection pressure for drug resistance; however, very little work has been performed to quantitatively assess the effectiveness of such methods. Methods: We analysed data obtained from 345 donkeys at The Donkey Sanctuary (Devon, UK), m...
Peregrine AS, Molento MB, Kaplan RM, Nielsen MK.Parascaris equorum and cyathostomins are currently considered the most important parasites of horses and have traditionally been controlled with anthelmintics belonging to three drug classes: benzimidazoles, the tetrahydropyrimidine pyrantel, and macrocyclic lactones. Unfortunately, resistance to benzimidazoles, and to a lesser extent pyrantel, is widespread in cyathostomins around the world. Furthermore, resistance to macrocyclic lactones appears to be in the early stages of development in cyathostomins in multiple locations. In contrast, P. equorum populations have remained susceptible to th...
Todhunter KH, Cawdell-Smith AJ, Bryden WL, Perkins NR, Begg AP.Pregnant mares were experimentally exposed to whole caterpillar or exoskeleton of the Processionary caterpillar (Ochrogaster lunifer) via gavage. Tissues were collected from resulting abortions and near or full-term pregnancies consisting of 13 aborted fetuses, 3 fetuses from treated euthanized mares, membranes of 5 foals, and organs from 3 foals. Three control membranes and 1 control fetus and membranes were examined. Caterpillar setal fragments were present in the allantochorion of the 3 fetuses from the euthanized mares and 11 of 12 aborted fetuses (92%) embedded in the chorion (villi or st...
Castagnolli KC, Ferreira BR, Franzin AM, de Castro MB, Szabó MP.This work evaluated the effect of the Amblyomma cajennense tick on the immune response of BALB/c mice and on horse lymph node cell proliferation. We observed that mice do not develop resistance to nymphs of this tick species and that lymphocyte proliferation of this host is inhibited by tick saliva, nymphal extract, or infestations. Horse lymph node cell proliferation is inhibited by tick saliva as well. Mice lymphocytes under the effect of tick saliva, nymphal extract, or infestations display a predominantly Th-2 cytokine production pattern. Observed results partially explain this tick's dise...
Stancampiano L, Usai F, Marigo A, Rinnovati R.Strongyle infections have been traditionally regarded as a possible cause of colic in horses. Aim of the study was the comparison of parasitological status between subjects with or without colic syndrome, with particular attention to small strongyle infections. Coprological analyses were performed on 86 horses: 43 with colic and 43 controls. Strongyle eggs were found in 34/86 horses (prevalence 39.5%), the mean number of strongyles eggs per gram of faeces (EPG) was 145.34 (standard deviation 398.28). All those 34 positive animals had small strongyles infections. Negative binomial multiple regr...
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...
Torres R, Hurtado C, Pérez-Macchi S, Bittencourt P, Freschi C, de Mello VVC, Machado RZ, André MR, Müller A.This study aimed to serologically and molecularly survey and in thoroughbred horses from racecourses in Chile. Additionally, the genetic diversity of the positive samples was assessed. A total of 286 thoroughbred horses from the Santiago and Valparaíso racecourses had their serum samples submitted to an ELISA for and , and 457 samples (from the Santiago, Valparaíso, and Concepción racecourses) were tested with nested PCRs for the 48 KDa rhoptry protein (RAP-1) and 18S rRNA genes. Selected RAP-1 and 18S positive products were sequenced to perform phylogenetic and haplotype analyses. An ...
Moreno SA, Concepción JL, Nava M, Molinari J.In Venezuela, horses are indispensable for extensive cattle raising, and extensive cattle raising prevails in all regions. This determines the numerical relationship between horses and cattle (r = 0.93) to be relatively constant nationwide. At regional level, the average extension of cattle ranches varies greatly. However, in relation to the area covered by pastures, the numbers of horses (r = 0.95) and cattle (r = 0.93) are relatively uniform nationwide. Water buffalo occupy small fractions of the territory; therefore, their numbers are related to the area of pastures less strongl...
Cain JL, Nielsen MK.The equine ascarids, Parascaris spp., are important nematode parasites of juvenile horses and were historically model organisms in the field of cell biology, leading to many important discoveries, and are used for the study of chromatin diminution. In veterinary parasitology, Parascaris spp. are important not only because they can cause clinical disease in young horses but also because they are the only ascarid parasites to have developed widespread anthelmintic resistance. Despite this, much of the general biology and mechanisms of anthelmintic resistance are poorly understood. This review co...
Léveillé AN, Bland SK, Carlton K, Larouche CB, Kenney DG, Brouwer ER, Lillie BN, Barta JR.Species in the genus Klossiella Smith and Johnson, 1902 are unique among the suborder Adeleorina because they are monoxenous in mammals exclusively, whereas all other reported members of the Adeleorina use invertebrates as definitive hosts. Unlike other coccidia, all members of the Adeleorina undergo syzygy, the association of microgamonts and macrogamonts before maturation to gametes and syngamy. After fertilization, many members of the Adeleorina produce thin-walled polysporocystic oocysts. Despite being biologically similar to other members of the Adeleorina, the phylogenetic placement of t...
Hodgkinson JE, Love S, Lichtenfels JR, Palfreman S, Ramsey YH, Matthews JB.Here, we report evaluation of five oligoprobes designed from intergenic spacer (IGS) region sequences for identification of cyathostomin species. Oligoprobes were designed for identification of Cylicocyclus ashworthi, Cylicocyclus nassatus, Cylicostephanus longibursatus, Cylicostephanus goldi and a fifth probe designed to identify all members of this tribe. PCR amplification of IGS DNA from 16 cyathostomin species allowed sequence comparison and identification of four putative species-specific probes. Southern blotting of amplified products from 16 species showed that all probes were species-s...
Macdonald SL, Abbas G, Ghafar A, Gauci CG, Bauquier J, El-Hage C, Tennent-Brown B, Wilkes EJA, Beasley A, Jacobson C, Cudmore L, Carrigan P, Hurley J....Cyathostomins are the most common and highly prevalent parasites of horses worldwide. Historically, the control of cyathostomins has mainly relied on the routine use of anthelmintic products. Increasing reports on anthelmintic resistance (AR) in cyathostomins are concerning. A potential method proposed for detecting emerging AR in cyathostomins has been estimating the egg reappearance period (ERP). This paper reviews the data available for the ERP of cyathostomins against the three major classes of anthelmintics, macrocyclic lactones, tetrahydropyrimidines, and benzimidazoles. Published peer-r...
Eysker M, Jansen J, Mirck MH.Alternate grazing of horses and sheep as a control measure for gastrointestinal helminthiasis was studied in three grazing experiments in 1981, 1982 and 1983. Each year a group of three mare yearling Shetland ponies, which were kept on a small pasture from spring to autumn, were compared with a similar group which grazed a similar or the same pasture until July and were subsequently removed to a similar pasture which had been grazed by sheep from April to July. In addition both groups were treated with an anthelmintic when the latter group was removed to the sheep pasture. Pasture larval count...
Cirak VY, Güleğen E, Bauer C.A cross-sectional survey was performed on ten stud farms in western Anatolia, Turkey, in order to provide the first information on the problem of anthelmintic resistance in equine strongyles in this country. Benzimidazole (BZ) resistant cyathostomin populations were detected on seven farms if pre- and post-treatment egg counts are compared in treated animals and the resistance is defined as a mean faecal egg count reduction (FECR) of <95% with a lower 95% confidence limit of <90%. Egg hatch tests using an ED(50) of 0.1 microg/ml thiabendazole as the cut-off value confirmed BZ resistance on fou...
Allison K, Taylor NM, Wilsmore AJ, Garforth C.An online survey was conducted to establish horse owners' beliefs, attitudes and practices relating to the use of anthelmintic drugs. Out of a total of 574 respondents, 89 per cent described themselves as 'leisure riders', most of whom took part in a variety of activities including eventing, show jumping, dressage, hunter trials, hunting, driving, endurance and showing. Overall, respondents were generally aware and concerned about the issue of anthelmintic resistance. Less than 60 per cent of all respondents were comfortable with their existing anthelmintic programme, and 25 per cent would lik...
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 ...
Nielsen MK, Vidyashankar AN, Gravatte HS, Bellaw J, Lyons ET, Andersen UV.Strongylus vulgaris is regarded as the most pathogenic helminth parasite infecting horses. Migrating larvae cause pronounced endarteritis and thrombosis in the cranial mesenteric artery and adjacent branches, and thromboembolism can lead to ischemia and infarction of large intestinal segments. A recently developed serum ELISA allows detection of S. vulgaris-specific antibodies during the six-month-long prepatent period. A population of horses has been maintained at the University of Kentucky without anthelmintic intervention since 1979, and S. vulgaris has been documented to be highly prevalen...
Zak A, Siwinska N, Slowikowska M, Borowicz H, Kubiak K, Hildebrand J, Popiolek M, Niedzwiedz A.There are no available studies describing the possible resistance of strongyles to ivermectin in horses in Poland. One hundred seventy three horses from nine stud farms from South-Western Poland were studied. The effectiveness of ivermectin was studied on the 14th day after ivermectin administration using the fecal egg count reduction test, and a long-term observation of the egg reappearance period was carried out. The fecal study was carried out using a modified McMaster method, which typically detects 20 eggs per gram of stool. The results were subjected to statistical analysis that enabled ...
Berlin D, Nasereddin A, Azmi K, Ereqat S, Abdeen Z, Eyal O, Baneth G.Trypanosoma evansi is the cause of surra in horses, camels and other domestic animals. Following the first outbreak of surra in horses and camels in Israel in 2006, a survey of the prevalence of the parasite in the Israeli horse population was conducted using serology, PCR followed by the reverse dot blot (RDB) technique and blood smear microscopy. In total, 614 horses from 7 regions were sampled. The CATT/T. evansi kit was used for serology for all the horses. Horses from the Arava and Dead Sea region, where the first outbreak occurred, were sampled again one year later and both samples were ...
Wells D, Krecek RC.Structured interviews using a questionnaire were conducted to gather information on socioeconomic aspects, health, nutrition, breeding and management of working equids in 3 study areas of Moretele 1 near Hammanskraal, North West Province, South Africa. The questionnaire addressed questions about the role of animals with a focus on donkeys used for work in these areas. Extension and animal health officers and donkey owners participated. The analysis highlights the use of donkeys for transport of water, wood and people; that ticks, wounds and harness sores are the conditions reported most freque...
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...
Dowdall SM, Proudman CJ, Love S, Klei TR, Matthews JB.Cyathostomins are important equine gastrointestinal parasites. Mass emergence of mucosal stage larvae causes a potentially fatal colitis. Mucosal stages are undetectable non-invasively. An assay that would estimate mucosal larval stage infection would greatly assist in treatment, control and prognosis. Previously, we identified two putative diagnostic antigens (20 and 25 kDa) in somatic larval preparations. Here, we describe their purification and antigen-specific IgG(T) responses to them. Western blots confirmed the purity of the antigens and showed that epitopes in the 20 kDa complex were sp...
Ryu SH, Bak UB, Kim JG, Yoon HJ, Seo HS, Kim JT, Park JY, Lee CW.A 7-year-old Thoroughbred horse was admitted to the Equine Hospital, Korea Racing Association with signs of colic. Based on the size of impactions, the clinical signs, the results of abdominal paracentesis and medical treatment, the prognosis was poor. The horse died 3 hours later following hopeless discharge. At necropsy, the caecum and large colon were fully filled with fecal contents and there was a rupture (10 cm in dia) in the latero- ventral caecum. The mucosa of the ileo-caecal and caeco- colic valves appeared to the hyperemic, edematous and ulcerous. There were many tapeworms in the af...
Acosta Ida C, Da Costa AP, Gennari SM, Marcili A.Trypanosoma and Leishmania infections affect wild and domestic animals and human populations. The growing process of deforestation and urbanization of Atlantic Rainforest areas has given rise to introduction of humans and domestic animals to the sylvatic cycles of Trypanosoma and Leishmania species. Serological, parasitological, and molecular surveys among wild and domestic animals in the Corrego do Veado Biological Reserve, which is an Atlantic Rainforest fragment in the state of Espírito Santo, southeastern Brazil, were evaluated. In total, 154 wild animals of 25 species and 67 domestic ani...
Bianchi MV, Mello LS, Wentz MF, Panziera W, Soares JF, Sonne L, Driemeier D, Pavarini SP.Diseases related to the alimentary system are the main cause of death in horses. This retrospective study aimed to describe the pathological findings of fatal parasite-induced enteritis and typhlocolitis caused by cyathostominae, Eimeria leuckarti, Balantidium coli, and Strongyloides westeri in horses. The records of parasite-induced intestinal lesions in horses necropsied in Southern Brazil between 2005 and 2017 were reviewed. Ten horses had fatal parasitic enteritis and/or typhlocolitis, and the main causes were: cyathostominae typhlocolitis (6/10), E. leuckarti enteritis (1/10), S. westeri ...
Reinemeyer CR, Prado JC, Nielsen MK.Despite widespread acknowledgement of cyathostomin resistance to adult icidal dosages of benzimidazole (BZD) anthelmintics, many strongyle control programs continue to feature regularly scheduled larvicidal treatment with fenbendazole (FBZ). However, no studies have been conducted to evaluate the efficacy of larvicidal regimens against encysted cyathostomins in a BZD-resistant (BZD-R) population. A masked, randomized, controlled clinical study was conducted with 18 juvenile horses harboring populations of cyathostomins that were considered BZD-R on the basis of fecal egg count reduction (FECR)...
Murphy AJ, Mansfield LS.Sarcocystis neurona is a protozoan parasite that causes a neurological disease in horses called equine protozoal myeloencephalitis. The route of transmission is speculated to be by fecal-oral transfer of sporocysts shed from opossums. Controversy exists regarding both the natural life cycle for this parasite as well as the species identity of opossum Sarcocystis. To provide stage-specific material for species comparison, 27 opossums from southern Michigan were screened for Sarcocystis spp. sporocysts. Seven opossums were positive for Sarcocystis sporocysts by fecal flotation. A simplified, eff...
Crotch-Harvey L, Thomas LA, Worgan HJ, Douglas JL, Gilby DE, McEwan NR.Anthelmintics are used as anti-worming agents. Although known to affect their target organisms, nothing has been published regarding their effect on other digestive tract organisms or on metabolites produced by them. The current work investigated effects of fenbendazole, a benzimidazole anthelmintic, on bacteria and ciliates in the equine digestive tract and on and their major metabolites. Animals receiving anthelmintic treatment had high faecal egg counts relative to controls. Analysis was performed over two weeks, with temporal differences detected in bacterial populations but with no other ...
Abdullah HHAM, Elbayoumy MK, Allam AM, Ashry HM, Abdel-Shafy S.Vector-borne bacterial diseases (VBBD) are a diverse group of tropical and subtropical zoonotic diseases. This study investigated the possibility of domestic animals to carry certain vector-borne bacterial microorganisms (VBBMs), as well as the presence of these targeted DNAs in their ectoparasites in different localities of Egypt using molecular analyses. For this study, 234 animal hosts (112 cattle, 38 sheep, 28 goats, 26 buffaloes, 22 donkeys, and 8 horses) in addition to 115 ectoparasites (95 ticks and 20 lice) were investigated for the molecular detection of Bartonella spp., Borrelia spp....
Bishop RM, Scott I, Gee EK, Rogers CW, Pomroy WE, Mayhew IG.To ascertain whether resistance was present in Parascaris equorum to the macrocyclic lactone anthelmintic ivermectin, using faecal egg count reduction tests. Methods: Thirty-nine foals aged between 11 and 28 weeks on three Thoroughbred stud farms (Farms A; n=20, B; n=5 and C; n=14) were treated with ivermectin (Day 0) and faecal egg counts (FEC) were monitored before and for 21 (Farms A and B) or 14 (Farm C) days after treatment. On Farms A and B, the foals were treated with a macrocyclic lactone/benzimidazole/praziquantel combination on Day 21 and FEC assessed on Day 35. The three farms were ...
Ramalho Sousa S, Anastácio S, Nóvoa M, Paz-Silva A, Madeira de Carvalho LM.In Portugal, equine parasitism in pasture animals is characterized by high parasitic burden and high helminthic biodiversity; both factors are potentially pathogenic for their hosts. The decrease in the number of donkeys over the last years in Portugal, their importance in rural lowland and mountain ecosystems and pastures and the scarce information regarding their parasitism led to this research, which aimed to evaluate the parasitological status of a Miranda donkey breed population, a native breed mainly located in the northeast of Portugal. This study provides better knowledge of their gast...
Selmi R, Dhibi M, Ben Said M, Ben Yahia H, Abdelaali H, Ameur H, Baccouche S, Gritli A, Mhadhbi M.Livestock constitute habitual hosts and carriers for several infectious pathogens which may represent a serious public health concern affecting the readiness of military forces and lead to wide economic losses. The present report aimed to investigate the prevalence of some haemopathogens infecting military livestock, particularly, dromedaries, sheep and horses using Giemsa-stained blood smears. A total of 300 animals (100 from each species) were selected, clinically examined and sampled. Trypanosoma spp. (22.0%), Anaplasma spp. (17.0%) and Babesia spp. (1.0%) were identified in camels' blood. ...
Hammerschmitt ME, Henker LC, Lichtler J, da Costa FVA, Soares RM, Llano HAB, Pavarini SP.Sarcocystis neurona is the main agent associated with equine protozoal myeloencephalitis (EPM). Apart from horses, S. neurona has been occasionally described causing neurologic disease in several other terrestrial animals as well as mortality in marine mammals. Herein, we describe the clinical, pathological, and molecular findings of a fatal case of S. neurona-associated meningoencephalitis in a domestic cat. The causing agent was analyzed by multilocus genotyping, confirming the presence of S. neurona DNA in the tissue samples of the affected animal. Significant molecular differences were fou...
