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.
Höglund J, Nilsson O, Ljungström BL, Hellander J, Lind EO, Uggla A.The egg output and humoral antibody response to scolex antigens of the equine tapeworm Anoplocephala perfoliata were monitored in naturally infected foals by an egg flotation/centrifugation method and an indirect enzyme-linked immunosorbent assay (ELISA). The study was performed on a stud farm in south-western Sweden between May 1994 and April 1995. Sequential blood and faecal samples were taken from 21 foals during their first summer on pasture and until tapeworm eggs were detected. Results were expressed separately for 10 and 11 foals born before and after the end of April 1994, respectively...
Monahan CM, Chapman MR, Taylor HW, French DD, Klei TR.Eighteen mixed-breed, naturally infected ponies ranging in age from 1 to 16 yr and four cyathostome-naïve ponies reared and maintained under parasite-free conditions ranging in age from 1 to 4 yr were used in this study. Naturally-infected ponies were treated with 1 dose of ivermectin (IVM) at 200 micrograms kg-1, followed by a 5-day regimen of oxibendazole (OBZ) at 20 mg kg-1 to remove existing cyathostome burdens; cyathostome-naïve control ponies were treated with IVM alone. The naturally infected ponies were matched on age and gender, then randomly assigned to one of three treatment group...
Dorchies P, de Lahitte JD, Flochlay A, Blond-Riou F.The efficacy of moxidectin 2% oral gel (Equest, Fort-Dodge) against European worm strains was studied through post-mortem worm counts and feacal egg counts (FECs) in 12 young ponies naturally infected. The animals were allocated in two groups of six ponies each: the first one was treated at 0.4 mg/kg b.w. and the second one received a placebo and served as control. All the ponies were necropsied 14 days post-treatment. The efficacy of moxidectin in reducing strongyle FECs ranged from 99.8% to 100% from 3 to 14 days after treatment. Moxidectin efficacy was 100% against Trichostrongylus axei and...
Meana A, Luzon M, Corchero J, Gómez-Bautista M.Three coprological methods were tested to establish the reliability of in vivo diagnosis of Anoplocephala perfoliata. A total of 107 faecal samples were analyzed, and the presence of tapeworms were confirmed postmortem in 24 animals with burdens that ranged from 1 to 248 worms; most of them (71%) with less than 100 parasites. Best results were obtained with a combination of two sedimentation/flotation methods, detecting only half the parasitized animals (54% sensitivity). No relationship could be established between tapeworm burden and egg detection, but results indicate that coprological meth...
Pozio E, Celano GV, Sacchi L, Pavia C, Rossi P, Tamburrini A, Corona S, La Rosa G.Epidemiological investigations conducted during 10 trichinellosis outbreaks between 1975 and 1994 showed that horse-meat was the probable source of infection. Though hundreds of thousands of horses have been examined at abattoirs in America and Europe to detect Trichinella infection by artificial digestion or trichinelloscopy, an infected horse has never been detected during routine analysis, which consists of examining 1 g of tissue muscle from the diaphragm. In November 1996, a naturally infected horse imported from Romania was detected in Southern Italy. The parasite was identified as Trich...
Boersema JH, Eysker M, van der Aar WM.The reappearance of strongyle eggs in the faeces of horses treated with moxidectin (0.4 mg/kg of body weight) was compared with that in the faeces of horses treated with ivermectin (0.2 mg/kg of body weight). The study was performed from December 1995 till June 1996. Horses were infected naturally in the preceding grazing period. Two groups of 24 horses each were treated with moxidectin and ivermectin respectively at week 0. No side effects were seen after treatment. Horses were housed from week -1 till week 17. From week 17 onwards the horses were on pasture. Faecal samples were taken from ea...
Mancebo OA, Verdi JH, Bulman GM.On the basis of positive skin snips for Onchocerca cervicalis microfilariae (MF), 45 horses were chosen from 48 in a total of 257 screened on 12 locations in the northeast Province of Formosa (Argentina), and randomly assigned to two treatment groups of 20 horses each, and a nontreated control group of five horses. On Day 14 post-treatment (PT), skin snip samples in the ivermectin-treated (0.2 mg/kg) group were negative for normal viable microfilariae (MF), while horses in the control group maintained their pretreatment level of infection. On the same Day in the moxidectin-treated (0.4 mg/kg) ...
Williamson RM, Gasser RB, Middleton D, Beveridge I.The intestinal tracts of 130 horses were examined for infection with Anoplocephala perfoliata at necropsy. Fifty horses (38.5%) harboured the tapeworm, and the site of attachment of each worm was recorded using predetermined anatomical landmarks. The worms were attached in four regions of the gastrointestinal tract: 17% of the worms were found at the ileocaecal junction, 81% on the caecal wall, 1.7% in the terminal ileum and 0.2% in the ventral colon. The severity of lesions produced at the sites of attachment was related to the number of worms attached. Due to the small area of the ileocaecal...
Fernández AS, Larsen M, Nansen P, Grønvold J, Henriksen SA, Wolstrup J.A plot experiment was conducted to investigate the ability of the nematode-trapping fungus Duddingtonia flagrans to reduce the transmission of infective horse strongyle larvae from deposited dung onto surrounding herbage. At three different times during the summer 1995, three groups of horses, naturally infected with large and small strongyles, were fed different doses of D. flagrans spores, while a fourth group of animals served as non-fungal controls. Faeces from all four groups of horses were deposited as artificial dung pats on a parasite-free pasture. Every second week for 8 weeks after d...
Sahagun-Ruiz A, Waghela SD, Holman PJ, Chieves LP, Wagner GG.A DNA probe from Babesia caballi (Bc1) was selected by antibody screening of a genomic library. The Bc1 probe hybridized specifically to B. caballi genomic DNA. A polymerase-chain-reaction-based assay for B. caballi DNA was developed from primers deduced from the probe nucleotide sequence. An amplified product of 1.6 kb was detected from as little as 500 fg B. caballi template DNA. Sensitivity increased 1000-fold when the biotin-labeled Bc1 probe was hybridized to the amplicons in a Southern blot.
Monahan CM, Chapman MR, Taylor HW, French DD, Klei TR.Three groups of foals were raised under different management programs in this study: Group 1 (n = 6) and Group 2 (n = 6) were raised with their dams on pasture; Group 3 foals (n = 5) were raised under parasite-free conditions. Mares and foals of Group 1 received daily pyrantel tartrate (PT) treatment with their pelleted feed ration, whereas mares and foals of Groups 2 and 3 received only the pelleted ration. Pasture-reared foals were weaned and moved to a heavily contaminated pasture for 5 weeks. Group 1 foals continued to receive daily PT treatment whereas Group 2 foals received only the pell...
Borgsteede FH, van Beek G.The prevalence of metazoan parasites in the stomach and small intestine was investigated in 70 horses slaughtered in the period February 1994-July 1994. Most horses were young (1.5-3 years) and in good condition. Trichostrongylus axei was the most prevalent parasite species in the stomach (51.4%), followed by Gasterophilus intestinalis (41.4%) and Habronema spp. (4.3%). In the small intestine, Parascaris equorum (28.6%) and Paranoplocephala mamillana (1.4%) were found. The mean worm burden of T. axei was 957 (max. 8502), of G. intestinalis 21 (max. 84), of Habronema spp. 3 (max. 5), and of P. ...
Pozio E, Tamburrini A, Sacchi L, Gomez Morales MA, Corona S, Goffredo E, La Rosa G.Routine examination for Trichinella infection by artificial digestion of 5-g samples of muscle tissue revealed the presence of muscle larvae in one out of 28 horses imported from Romania to an abattoir in Italy. The parasite, identified as Trichinella spiralis by the polymerase chain reaction, showed a reproductive capacity index of 68 in Swiss mice. Light microscope examination of 200 nurse cell-larva complexes showed that 22% of them were calcified and that the capsules of the non-calcified nurse cells were 17.5-27.5 microns (s = 22.67 microns) thick and had very few cellular infiltrates. Th...
Larsen M, Nansen P, Grønvold J, Wolstrup J, Henriksen SA.The potential of using fungi to prevent nematodosis caused by parasites with free-living larval stages is well documented today. In this respect Duddingtonia flagrans, a net-trapping, nematode-destroying fungus, appears to be the most promising candidate. Laboratory experiments and in-vivo studies, where fungal spores have survived passage through the gastro-intestinal tract of cattle and horses, plus field studies with cattle, horses and pigs, demonstrate significant reduction in the number of infective larvae that develop in the faecal environment. In field trials this reduction subsequently...
Murphy D, Reid SW, Graham PA, Love S.Validation of an assay for measurement of fructosamine in equine serum and plasma utilised blood samples collected from 24 British native breed ponies. The results indicated that fructosamine can be measured easily using an assay which is precise and accurate. Paired plasma and serum fructosamine measurements were highly correlated, however, greater variations were observed within serum compared with those in plasma. A reference range for fructosamine in plasma was calculated to be 256.9 +/- 60.6 mumol litre-1 (mean +/- 2 SD). In order to assess the fructosamine response following experimental...
Gorman T, Aballay J, Fredes F, Silva M, Aguillón JC, Alcaíno HA.Crude and partially purified somatic (S) and excretory-secretory (ES) antigens of Fasciola hepatica were subjected to Western blot analysis in order to identify polypeptides that would enable specific and sensitive immunodiagnosis of horse and pig fasciolosis to be undertaken. Sera from 20 horses and 20 pigs with natural infections of F. hepatica and the same number of uninfected hosts of each species were tested, together with sera from 2 pigs with Cysticercus cellulosae infections. Using crude S antigens, sera from infected horses and pigs reacted specifically with a wide range of polypeptid...
DiPietro JA, Hutchens DE, Lock TF, Walker K, Paul AJ, Shipley C, Rulli D.A clinical trial carried out over 98 days was done to evaluate treatment of horses with moxidectin gel for efficacy as measured by (1) reduction in the production of parasite ova post treatment, (2) a comparison of the posttreatment parasite egg count suppression of moxidectin to ivermectin, and (3) assessment of the field safety, animal acceptance of the moxidectin formulation, and the utility of the moxidectin delivery device. One hundred and fifty Standardbred horses with naturally acquired parasite infections were used in the study. Moxidectin had more prolonged and greater suppressive inf...
Demeulenaere D, Vercruysse J, Dorny P, Claerebout E.The control of naturally acquired cyathostome infections in horses by treatments with ivermectin and moxidectin was evaluated in three field studies. In a first study the efficacy of both drugs was assessed in a faecal egg count reduction test. Both ivermectin and moxidectin demonstrated efficacies greater than 99 per cent for up to 60 days after treatment. In a second study, the period required for strongyle eggs to reappear was estimated in horses treated either with ivermectin or moxidectin. For the horses treated with ivermectin the period varied between 10 and approximately 13 weeks, and ...
Medica DL, Sukhdeo MV.Infective larvae (L3) of Strongylus vulgaris have limited energy stores for host finding and for infection. For transmission to occur, the larvae must have sufficient energy to (a) migrate onto grass, where they are ingested by their equine host (host finding), and (b) penetrate into the host gut. This study is designed to test the hypothesis that L3 larvae of S. vulgaris partition their energy stores between locomotory activity (used in host finding) and infection activity (penetration). Chronic locomotory activity was stimulated by incubating S. vulgaris L3 larvae at a constant temperature (...
Dabareiner RM, White NA.The cecum is an important site of water and electrolyte absorption, as well as microbial digestion of soluble and insoluble carbohydrates. These functions of the cecum and ascending colon require that ingesta be mixed constantly and retained long enough to complete the digestion of cellulose. Parasites, changes in regional blood flow, diet, and various pharmacologic agents are associated with alterations in normal cecal motility patterns.
Brown CA, MacKay RJ, Chandra S, Davenport D, Lyons ET.A 6-month-old foal was evaluated because of weakness, weight loss, and inappetence of 3 weeks' duration. On initial examination, the foal was weak, poorly responsive, and emaciated. Clinicopathologic abnormalities included anemia and hypoproteinemia. Because of its severe debilitation, the foal was euthantized. Necropsy revealed marked infection of the small intestine with Strongyloides westeri and severe edema of the entire gastrointestinal tract. The foal had been orphaned when it was 6 hours old and raised in isolation from other horses. We believe that this foal developed overwhelming stro...
Beelitz P, Gothe R.In this epidemiological study 127 horses from five breeding farms in Upper Bavaria were included. The horses were coproscopically examined in intervals of four weeks over a 16-month period. Since 1992 in all farms regular prophylactic treatments with anthelmintics have been carried out. In 127 horses at least five species were established, such as Parascaris equorum, Anoplocephala perfoliata, Gasterophilus intestinalis and small strongyles, whose third stage larvae were characterized by eight or twelve intestinal cells. Infections with small strongyles occurred most frequently, followed by G. ...
Lyons ET, Tolliver SC, Collins SS, Drudge JH, Granstrom DE.Data are presented on the last 3 years of a 7-year study (1989-1995) on transmission of natural infections of internal parasites in horse foals (n = 27) born in 1993, 1994, and 1995 on the same pasture on a farm in central Kentucky. The foals were in a closed breeding herd of horses. Research on the first 4 years (1989-1992) of the study was published earlier (Lyons et al., 1991, 1994). Thirty-five species of endoparasites were identified, including 24 species of small strongyles. Monthly, seasonal, and host-age transmission patterns were elucidated for the parasites. Comparison of data betwee...
Eysker M, Boersema JH, Grinwis GC, Kooyman FN, Poot J.The efficacy of a 2% moxidectin equine gel at a dosage rate of 0.4 mg kg-1 was evaluated in a controlled trial at Utrecht University. Twelve yearling castrated male Shetland ponies grazed a pasture of 2 ha from May 1994 until housing in November. Six ponies were treated with moxidectin, whereas the others served as non-treated controls. Necropsy was carried out 35 days after treatment. Greater than 99% efficacy of moxidectin was observed on faecal egg output. No effect of moxidectin was observed on mucosal inhibited early cyathostome L3 (EL3) or on the total numbers of mucosal developing stage...
Avarzed A, De Waal DT, Igarashi I, Saito A, Oyamada T, Toyoda Y, Suzuki N.Antigen for the indirect fluorescent antibody test (IFAT) was routinely prepared from infected erythrocytes from horses experimentally infected with Babesia equi and Babesia caballi. With the successful establishment of in vitro cultures of B. equi and B. caballi, it is now possible to employ culture-derived antigens in this test. In this study, in vitro-propagated B. equi- and B. caballi-infected erythrocytes were used as antigen in the IFAT. Various modifications to an established protocol had to be implemented to allow repeatable results. Cultures with 3-4% parasitized erythrocytes were fou...
Foster AP, McCabe PJ, Sanjar S, Cunningham FM.Eosinophils are believed to play an important part in the pathogenesis of equine diseases such as helminth infestation and the allergic skin disease, sweet itch. It has been shown that adherence of human eosinophils to the connective tissue matrix protein fibronectin enhances cell activation and survival time. If adherence causes similar changes in the properties of equine eosinophils, cell-induced tissue damage at a site of parasitic infestation or allergic response would be exacerbated. However, investigation of this hypothesis requires identification of mediators that cause equine eosinophi...
Kumar S, Malhotra DV, Dhar S.The present study aimed to develop Dot-ELISA, complement fixation test (CFT) and capillary tube agglutination test (CAT) for serodiagnosis of Babesia equi infection and to compare their sensitivity with each other. For this study, sequential serum samples were collected from four donkeys experimentally infected with B. equi up to 90 days post infection (P.I.). B. equi antigen was prepared from the blood of a donkey showing more than 80% parasitaemia. Dot-ELISA, CF and CA tests were standardized as per the standard method. While performing CFT, it was observed that CFT standardized for the donk...
Nielsen MK, Martin AN, Scare JA, Steuer AE.Cyathostomins are pervasive parasites of equids across the world. Larval stages encyst in the mucosa of the cecum, ventral and dorsal colon and can induce an inflammatory response leading to larval cyathostominosis, a life-threatening generalized typhlocolitis. Mucosal digestion is the only gold standard procedure for identifying and quantifying all larval stages. There is a lack of standardization of this technique and several aspects are ambiguous, such as precision of the method and the possibility of spatial variation of mucosal larval counts. The aim of this study was to estimate precisio...
Webster JH, Baird JD, Gunawan M, Martin IC, Kelly JD.The susceptibility of a known thiabendazole-resistant population of small strongyles to anthelmintics of both benzimidazole and non-benzimidazole groups, was determined. In the first study, 42 horses infected with thiabendazole-resistant small strongyles were allocated to 6 groups. Treatment groups received one of the following anthelmintics: mebendazole, febantel, febantel plus trichlorphon, morantel tartrate, or a combination of thiabendazole, piperazine and trichlorphon. Morantel tartrate and the thiabendazole/piperazine/trichlorphon combination produced highly significant (p less than 0.00...
Wilkes EJA, Cowling A, Woodgate RG, Hughes KJ.Faecal egg counts (FEC) are used widely for monitoring of parasite infection in animals, treatment decision-making and estimation of anthelmintic efficacy. When a single count or sample mean is used as a point estimate of the expectation of the egg distribution over some time interval, the variability in the egg density is not accounted for. Although variability, including quantifying sources, of egg count data has been described, the spatiotemporal distribution of nematode eggs in faeces is not well understood. We believe that statistical inference about the mean egg count for treatment decis...
Alshammari A, Gattan HS, Marzok M, Salem M, Al-Jabr OA, Selim A.Fasciola hepatica is a trematode parasite that affects wide range of mammalian hosts including horses. There are no epidemiological data on fasciolosis in Egyptian horses. Hence, the present study aimed to evaluate the seroprevalence of F. hepatica in horses using ELISA as well as assess the associated risk factors for fasciolosis infection. A total of 400 sera samples of horses from three Egyptian governorates were examined. The overall seroprevalence rate in horses was 13% and the disease was more prevalent in Qalubia (14.17%) and Gharbia (16.67%) which are located at Nile Delta. The likelih...
Yadav SC, Kumar R, Kumar J, Singh M, Bera BC, Kumar R, Tatu U, Tehri K.Trypanosoma evansi is a haemo-protozoan parasite responsible for the disease surra, an economically important disease of wide range of domestic and wild animals. The present diagnostic methods using soluble antigens have inherent problems like lack of standardized and reproducible antigens, as well as ethical issues. This entails further efforts for search of defined antigenic molecules with satisfying sensitivity and specificity for sero-epidemiology of trypanosomosis. In present investigation, we have identified and purified 52-55kDa immuno-dominant protein cluster in molecular mass ranges b...
Nielsen MK, Lyons ET.Cyathostomins (small strongyles) are ubiquitous in grazing horses and are known pathogens as cause of larval cyathostominosis. As part of their life cycle, cyathostomin larvae invade the mucosal walls of the large intestines and undergo encystment. Newly ingested third stage larvae are known to undergo arrested development and this can lead to an accumulation of encysted burdens over the course of a grazing season. It is believed that the host immune system plays a significant role in triggering this arrestment. Little is known about the development and progression of larval stages in foals th...
Lv K, Zhang Y, Yang Y, Liu Z, Deng L.Equine piroplasmosis (EP) is a type of blood protozoan disease caused by tick-borne parasites, (), () and . While many studies have been conducted on EP diagnosis, diagnostic methods exhibiting high sensitivity and specificity remain lacking. Therefore, nested PCR (nPCR) and duplex real-time fluorescence quantitative PCR (qPCR) that can simultaneously detect both and causing agents were established and compared. The two techniques were used to analyze 36 horse blood samples for EP. This set of samples was also detected by a multinested PCR (mnPCR) targeting the gene of and the gene of ....
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...
Ellse L, Sands B, Burden FA, Wall R.Chewing lice are widespread and clinically compromising parasites of livestock and equids. Their management is complicated by growing levels of resistance to commonly applied insecticides. Hence, the development of novel approaches to their control is of major clinical interest. Objective: To assess the effects of incorporating the essential oils of tea tree and lavender into a grooming programme for populations of donkeys with natural infestations of Bovicola ocellatus in the UK and Ireland when louse populations were at their winter seasonal peak. Methods: In vivo field trial. Methods: Suspe...
Araujo JM, Araújo JV, Braga FR, Carvalho RO.Three isolates of predator fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34), and Arthrobotrys robusta (I-31) were assessed in in vitro test regarding the capacity of prey infective larvae (L(3)) Strongyloides westeri. Compared to control, without fungus, there was a significant decrease (P 0.01) in vitro test. Linear regression coefficients of treated and control groups were -0.21 for control, -0.32 for D. flagrans, -0.34 for M. thaumasium, and -0.22 for A. robusta. In the following, isolates AC001 and NF34 were assessed in vivo regarding the capacity of supporting the pa...
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 ...
Souza EAR, Araujo AC, Pires LCSR, Freschi CR, Azevedo SS, Machado RZ, Horta MC.Equine piroplasmosis, an economically important disease in horses, has so far not been reported in Pernambuco state, Brazil. This study aimed to evaluate the seroprevalence of anti-Babesia caballi and anti-Theileria equi antibodies based on the detection of these agents in equine blood and in ticks on horses in the municipality of Petrolina, Pernambuco, northeastern Brazil. Blood samples were drawn from 393 horses and sera were examined by ELISA. The presence of tick infestations was evaluated, and 101 ticks were subjected to DNA amplification for the detection of Babesia spp. by polymerase ch...
Creton B, Pageat P, Robejean M, Lafont-Lecuelle C, Cozzi A.Hematophagous insects can be vectors of pathogens and cause significant economic loss in zootechnical production. Among biting insects, many dipteran species feed on horse blood. The black fly (Diptera: Simuliidae) group, is responsible for several disorders in horses and inflicts painful bites that lead to undesirable behaviours in horses, particularly when bites occur in sensitive areas such as the inner ear. A field study was conducted in a French equestrian center during which a semiochemical was applied on horses' ears to assess repellent efficacy against simulid infestation. During the f...
Dewes HF, Townsend KG.Two horses repeatedly underwent episodes of frenzy characterised by extreme discomfort and hyperactivity. Within 2 days of an attack the lower extremities of both hind legs of one subject were uniformly swollen, while on the second subject skin lesions erupted 3-4 days after an attack and swelling persisted for 2-3 weeks. Filariform larvae of Strongyloides westeri were cultured from soil and sawdust where the subjects were kept. Larvae were cultured from soil of low pH (4.5-5.8) but were absent from neutral or alkaline soils. Larvae were found in sawdust with a wide pH range. It is thought tha...
Sallé G, Cortet J, Koch C, Gascogne T, Reigner F, Cabaret J.Drug resistance in equine gastro-intestinal parasitic nematodes has been reported throughout the world. While the focus is usually put on cyathostomins, observations of macrocylic lactone failure against Oxyuris equi have accumulated over the last decade. Here we report the failure of ivermectin in the control of O. equi in an experimental Welsh pony herd. In a first trial, 6 ponies previously drenched with moxidectin and showing patent O. equi infections were administered ivermectin and subsequently monitored for O. equi egg excretion over one month. This trial demonstrated a failure of iverm...
Chapman MR, Kearney MT, Klei TR.With the increased interest in equine cyathostomes it has become apparent that some evaluations of methods currently used to count the various larval stages which occur in the mucosa would be beneficial. Experiments were conducted to investigate the effects of fixation and storage of mucosal tissues at -20 C on the accuracy of counting these larvae. The accuracy of counting developing larvae within the mucosa by transmural illumination (TMI) and by artificial digestion (DIG) of the mucosa was also compared. The data indicate that fixation of digested mucosa in PBS-buffered 5% or 10% formalin d...
Andersen UV, Haakansson IT, Roust T, Rhod M, Baptiste KE, Nielsen MK.Strongyle and trichostrongyle parasites are ubiquitous nematodes of grazing livestock. Several molecular diagnostic tests are based upon measuring and quantifying DNA obtained from parasite eggs. It is well known that such eggs undergo development during storage, but it remains unknown to which extent developmental stages can affect the variation of diagnostic test results. This study investigated the influence of developmental stages of strongyle eggs on the variation real-time polymerase chain reaction (PCR) results. Mixed species strongyle eggs were obtained from the faeces of a naturally i...
Collobert-Laugier C, Hoste H, Sevin C, Chartier C, Dorchies P.From December 1998 to March 2000, caecum and ascendant colon of 42 horses naturally infected with cyathostomes were collected during routine necropsy or from a local slaughterhouse. Changes in the numbers of mucosal and submucosal mast cells (MMC and SMMC), intraepithelial, mucosal and submucosal eosinophils (IE, ME and SME) in the large intestine were investigated by histochemical techniques in relation to the worm burdens. The effect of age was examined in three subgroups: 6-24-month-old horses (group 1), 2-10-year-old horses (group 2) and horses more than 10 years of age (group 3). No globu...
Davis SW, Speer CA, Dubey JP.Asexual stages of Sarcocystis neurona were seen in cultured bovine monocytes (M617) inoculated with tissue homogenates from the spinal cord of a horse with naturally acquired protozoal myelitis. Organisms first were observed as intracytoplasmic schizonts and later as motile extracellular zoites capable of infecting surrounding M617 cells. Parasites most often occurred as clusters of merozoites dispersed throughout the host cell cytoplasm; however, schizonts also contained merozoites arranged in a radial fashion surrounding a prominent residual body. Schizonts divided by endopolygeny. The paras...
Araujo JM, Araújo JV, Braga FR, Tavela Ade O, Ferreira SR, Soares FE, Carvalho GR.Strongyloides westeri is the most prevalent nematode among equines aged up to four months and causes gastrointestinal disorders. The objective of this study was to observe the control of infective S. westeri larvae (L3) by the nematophagous fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34) after passage through the gastrointestinal tract of female donkeys. Twelve dewormed female donkeys that were kept in stables were used. Two treatment groups each comprising four animals received orally 100 g of pellets made of sodium alginate matrix containing a mycelial mass of either...
Bird J, Herd RP.The ability of two species of nematophagous fungi, Arthrobotrys oligospora and Arthrobotrys flagrans (syn. Trichothecium flagrans, Duddingtonia flagrans), to control the development of infective larvae in feces from naturally infected horses was assessed in vitro. The horses were from a farm where it had been previously established that cyathostomes accounted for 100% of the strongyle egg output. The feces from these naturally infected horses were mixed with spores of each fungal species at four concentrations: 0 (control), 1, 10, and 100 spores per egg. Five replicates for each group were inc...
Nogueira BCF, Orozco AMO, Argumedo AK, de Oliveira Faustino A, de Oliveira LL, da Fonseca LA, Campos AK.Ticks have saliva rich in immunoregulatory molecules that interfere with the host's physiology in order to feed. This study aimed to evaluate the concentration of acute phase proteins and circulating oxidative stress in response to infestation by Amblyomma sculptum and Dermacentor nitens in two breed horses, Mangalarga Marchador and Breton Postier, to define resistance or susceptibility to ticks. Among the oxidative stress markers, we observed lower malondialdehyde and nitric oxide in horses with tick infestation, consequently not altering the antioxidant enzymes. Breton Postier with tick infe...
Mahlobo-Shwabede SIC, Zishiri OT, Thekisoe OMM, Bakkes D, Bohloa L, Molomo M, Makalo MJR, Mahloane GR, Mtshali MS.A total of 3311 tick specimens were randomly collected from domestic animals including cattle, sheep, goats, horses, donkeys, and dogs from Lesotho districts namely, Berea, Butha-Buthe, Leribe, Mafeteng, Maseru, Mohale's Hoek, Mokhotlong, Qacha's Nek, Quthing and Thaba Tseka. Tick species were identified morphologically and verified by amplification and sequencing of the CO1 and 18S rRNA genes. Nine species were identified under different genera namely, Haemaphysalis elliptica 0.1% (n = 2), Hyalomma rufipes 2.6% (n = 87), Hy. truncatum 1.2% (n = 41), Otobius megnini 13.6% (n = 451), Rh...
Epe C, Woidtke S, Pape M, Heise M, Kraemer F, Kohlmetz C, Schnieder T.Two groups of 10 first-year grazing cattle were either left untreated as controls (group 1) or treated with eprinomectin as a pour-on application at turnout and eight weeks later (group 2). The control group developed a mild infection with gastrointestinal nematodes and lungworms during the season, whereas the treated animals remained healthy. The interval between the treatments allowed the establishment of adult worms, but the egg counts remained negligible. The total number of eggs shed by the treated cattle during the grazing season was significantly smaller than by the controls.
Hifumi T, Akioka K, Tanaka T, Miyoshi N.Alveolar echinococcosis, which is caused by a larval-stage infection of Echinococcus multilocularis, is a zoonosis with public health importance. Recently, alveolar echinococcosis in slaughtered horses has been reported in Japan and Poland. In terms of public health, a highly sensitive and specific diagnostic method is essential for early detection during meat inspection. In this study, the loop-mediated isothermal amplification (LAMP) assay was developed and validated to target the mitochondrial cytochrome b (cob) gene of E. multilocularis. Forty-one hepatic solid nodules obtained from each h...
Rakhshandehroo E, Sharifiyazdi H, Shayegh H, Ahmadi A.Habronema muscae is a spirurid nematode that undergoes developmental stages in the stomach of equids, causing chronic catarrhal gastritis. Despite preceding investigations have developed polymerase chain reaction (PCR)-based assays for molecular diagnosis, we aimed to assess the applicability of cytochrome c oxidase subunit 1 (cox1) sequences to identify the H. muscae infection and to assess the level of intraspecific variations in this parasite obtained from affected horses in Southern Iran. According to the morphological characterizations, two different isolates of H. muscae were identified....
Ramos MI, Hermosura ME, Nakabayashi T.Horse, calf and bovine serum were successfully used as human serum substitutes in the in vitro cultivation of Plasmodium falciparum. Positive results were obtained only after gradually adapting the parasites to the substitute serum. Adapted lines were established within 4-5 weeks. 10% horse serum was observed to be the best substitute with growth rates comparable or even surprising that obtained in human serum. Pure calf or bovine serum supported stable growths of 20-30% less which was enhanced to comparable levels after addition of 1% glucose-peptone to the medium. Direct transfers of adapted...
Elsener J, Villeneuve A.Fecal samples were examined immediately before and 24 to 48 h after cestocide treatment for a comparative detection of tapeworm-positive horses. In early winter, 17 weanlings, 20 yearlings, 15 2-year-old horses, 24 breeding mares, and 2 stallions were treated with praziquantel in combination with a macrocyclic lactone. The horses were presumed to be naturally infected with tapeworms after pasture grazing. Fecal samples were collected before treatment (Day 0), at 24 or 48 h after treatment (Day 1-2), and 16 to 21 d after treatment (Day 16-21). A Wisconsin test was done on all fecal samples. Odd...
Fifteen horses harboring naturally acquired, patent Parascaris equorum and Oxyuris equi infections were equally allotted to 3 treatment groups given (1) injectable vehicle; (2) injectable ivermectin at the dose rate of 200 microgram/kg of body weight; and (3) injectable ivermectin at the rate of 300 microgram/kg. All treatments were given IM in the neck. All animals were killed 14 days after treatment and examined for the targeted nematodes. Regardless of dose rate, ivermectin proved 100% effective in the removal of adult O equi and P equorum infections. Levels of immature P equorum were decre...
Peckle M, Pires MS, Dos Santos TM, Roier ECR, da Silva CB, Vilela JAR, Paulino PG, Santos HA, Massard CL.The epidemiological aspects of Babesia caballi infection were evaluated in 516 horse samples from Rio de Janeiro, Brazil. The presence and infestation level of ticks on horses, breed conditions, and animal management were evaluated on each farm through an epidemiological questionnaire. The gene that codes for rhoptry-associated protein-1 (RAP-1) of B. caballi was amplified by nested PCR (nPCR). Among the horses sampled, 17.2% (n = 89/516) presented B. caballi DNA. The characterized samples showed 99-100% similarity with other isolates of B. caballi based on the RAP-1 gene, available in GenBa...
