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.
Austin SM, DiPietro JA, Foreman JH, Baker GJ, Todd KS.Sixteen helminth-free pony foals were inoculated with a mean (+/- SD) 2,000 (+/- 545.5) infective Parascaris equorum eggs (day 0). Foals were allocated to replicates of 4, and treatments within each replicate were assigned at random. Treatment administered on postinoculation day (PID) 28 included no treatment (control), 0.2 mg of ivermectin/kg of body weight, 10 mg of oxibendazole/kg, or 6.6 mg of pyrantel base (pamoate)/kg. Paste formulations of the anthelmintics were administered orally. The foals were euthanatized 14 days after treatment (PID 42) and examined for P equorum larvae in the sma...
Posnett ES, Ambrosio RE.A genomic library of Babesia caballi DNA was constructed in the plasmid vector pUC13. The specificity of the clones for B. caballi was established by the lack of hybridization to Babesia equi, Babesia bovis, Babesia bigemina and equine DNA. Two probes, pBC11 and pBC191, were isolated that could detect 0.25 ng and 0.125 ng of B. caballi DNA, corresponding to a parasitaemia of 0.12% and 0.06% respectively. pBC191 could detect B. caballi parasites in the blood of an experimentally infected horse as well as in naturally infected horses.
Traub-Dargatz JL, Salman MD, Voss JL.This paper reports the results of a survey conducted among members of the American Association of Equine Practitioners, concerning medical problems of adult horses. A one-page questionnaire listing 36 medical problems grouped by body system was completed by 1,149 veterinarians. The top-ranked disease was colic, followed by viral respiratory tract disease, endometritis, dermatitis, and parasitism. When responses were evaluated by type of practice, location of practice, and number of veterinarians in the practice, ranking of the top 2 diseases was the same for the total respondents. Ranking of d...
Gomez HH, Georgi JR.A programme of selective anthelmintic therapy was used in a herd of 31 horses. Faecal egg counts were done during the months of September, November, January, March, May and the following September. Horses with greater than or equal to 100 eggs per gram (epg) were treated with ivermectin, and those with less than 100 epg were not treated. The criteria for adequate internal parasite control in the herd was a median herd faecal egg count of less than or equal to 100 epg. Effectiveness of selective therapy was assessed by faecal egg count after nine months of treatment and was determined to be ade...
Weiland G, Hasslinger MA, Mezger S, Pöllein W.In an investigation period over 8 months the natural course of infection was studied by means of coproscopic and serological methods in 27 mares and 29 foals. The examination of the stool showed in mares, before the beginning of the grazing season, an infection rate of 100% with small and a rate of 7.4% with large strongyles (Str. vulgaris). Serologically the ELISA showed in foals only a distinct increase of antibody activity with the somatic antigen. The mares retained the high IgG-values of activity, which were already found at the beginning of the investigations. Even though the agglutinati...
Greiner EC, Mays MB, Smart GC, Weisbrode SE.Verminous mastitis was the reason for euthanasia of a 22-yr-old Paso Fino mare from Miami, Florida. The etiologic agent was a species of Cephalobus (Rhabditida: Cephalobidae), a genus of soil-inhabiting nematodes that were obviously multiplying in the mammary gland. Only females and larvae were detected in the tissues by histologic section or by teasing the tissue to liberate the worms. At least 12,900 individuals were present per gram of tissue. This is the first case of Cephalobus infecting horses and it indicates that not all histiotropic infections of horses by rhabditoid nematodes are by ...
Bello TR.A controlled test was done in 30 naturally infected ponies to evaluate the antiparasitic activity of the dienbendazole analog VET 220-S given alone or with trichlorfon (TCF) by nasogastric intubation. Six ponies were nontreated; 6 were given VET 220-S (5.0 mg/kg); 6 were given TCF (40 mg/kg); 6 were given VET 220-S (2.5 mg/kg) and TCF (40 mg/kg); and 6 were given VET 220-S (5.0 mg/kg) and TCF (40 mg/kg). All ponies were euthanatized and necropsied 7 or 8 days after treatment. Draschia megastoma, Oxyuris equi, Strongylus vulgaris, S edentatus, and small strongyles were removed efficaciously by ...
Dubey JP, Davis SW, Speer CA, Bowman DD, de Lahunta A, Granstrom DE, Topper MJ, Hamir AN, Cummings JF, Suter MM.Sarcocystis neuronan n. sp. is proposed for the apicomplexan taxon associated with myeloencephalitis in horses. Only asexual stages of this parasite presently are known, and they are found within neuronal cells and leukocytes of the brain and spinal cord. The parasite is located in the host cell cytoplasm, does not have a parasitophorous vacuole, and divides by endopolygeny. Schizonts are 5-35 microns x 5-20 microns and contain 4-40 merozoites arranged in a rosette around a prominent residual body. Merozoites are approximately 4 x 1 micron, have a central nucleus, and lack rhoptries. Schizonts...
Pereira MC, Kohek Júnior I, Campos R, Lima SB, Foz RP.The anthelmintic efficacy of ivermectin (IVM), piperazine citrate (PPZ) and fenbendazole (FBZ) alone, and combinations of FBZ with varying dosages of PPZ, was evaluated for the control of strongyles of Mangalarga equids. In all cases of positive strongly egg counts per gram of faeces (EPG) before and after treatment, pure populations of cyathostome larvae with eight gut cells were consistently observed in faecal cultures. The faecal egg count reductions (FECR) were evaluated between Day 7 and Day 56 post-treatment. Significant differences (P less than or equal to 0.05) were found between Day 7...
Payne RC, Sukanto IP, Djauhari D, Partoutomo S, Wilson AJ, Jones TW, Boid R, Luckins AG.Cattle, buffaloes and horses in several areas of Indonesia were examined for evidence of infection with Trypanosoma evansi by the microhaematocrit centrifugation technique (MHCT) and an enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to T. evansi. Evidence of infection was found in animals at each sampling site although differences were seen in prevalence rates between sites. Prevalence rates in buffalo were usually higher than in cattle in the same area while in horses they were much lower than in cattle or buffalo. An age-dependent prevalence rate was seen in buffalo an...
Wright JD, Kelly WR, Waddell AH, Hamilton J.Verminous encephalomyelitis due to Angiostrongylus cantonensis larvae was diagnosed in 2 foals at necropsy. The principal clinical feature was tetraparesis, although history and neurological examination revealed progressive and multifocal neurological disease. At presentation, a tentative diagnosis of parasitic larval migration involving the central nervous system (CNS), presumably due to Strongylus vulgaris, was proposed. Dissection of the spinal cord in one case resulted in recovery of intact larvae of both sexes of A. cantonensis. In both foals, histopathology of the brain and spinal cord r...
Piché CA, Kennedy MJ, Herbers HA, Newcomb KM.Thirty resident horses at a boarding stable in Alberta were used to evaluate the relative efficacies of ivermectin, oxibendazole, and pyrantel pamoate in reducing fecal egg output in adult horses under routine management conditions during spring and early summer, and to more clearly define the duration of suppression of fecal egg production following anthelmintic treatment. Horses were blocked according to pretreatment egg counts and randomly assigned to one of three treatments: pyrantel pamoate at 6.6 mg/kg body weight; oxibendazole at 10 mg/kg body weight; or ivermectin at 200 mug/kg body we...
Bhushan C, Müller I, Friedhoff KT.A rapid and simple method for concentrating leucocyte-free Babesia caballi-infected erythrocytes from in vitro cultures is described. Infected erythrocytes amounted to at least 95% of all red cells obtained.
Bjørn H, Sommer C, Schougård H, Henriksen SA, Nansen P.This study was undertaken to establish whether anthelmintic resistance was present in nematode parasites of horses in Denmark. Sixteen horse farms were selected for faecal egg count reduction (FECR) tests to measure the efficacy of the anthelmintic used. Resistance to benzimidazole anthelmintics was found on 13 of the 16 farms, with FECR values ranging from 80.0% to -101.3%. On the remaining 3 farms FECR was 100.0%, 99.3% and 97.2%. Results of a questionnaire study on anthelmintic usage, parasite control measures and management practices showed that horses in this study were treated on average...
Brocard P, Pfister K.Between March 1988 and December 1989, 198 gastrointestinal tracts from slaughtered horses from different areas of Switzerland have been analysed for the presence and the frequency of Gasterophilus spp. During the same period--always between July and November--200 horses from selected areas of Western Switzerland have been checked for the presence of eggs and their subsequent developmental stages in order to investigate further clinical and biological aspects of this infection. The evaluation has been performed according to origin, age, sex, colour of the horse and seasonal pattern of the cases...
Cope SE, Catts EP.Parahost behavior of adult Gasterophilus intestinalis (DeGeer) was observed during the summers of 1978 and 1979 near pastured horses on two farms near Newark, Del. Adult fly occurrence, although sparse in early summer, indicated a gradual increase, with three surges in emergence. In the laboratory, males lived 1-3 d and females 1-2 d. In the field, marked flies were not seen on days following their release. Adult behavior indicated an urgency in mating and oviposition dictated by a short life span. Male flight patterns were characterized by in-flight searches for females and intraspecific conf...
Eysker M, Boersema JH, Kooyman FN.Two groups of three ponies were used to study the effect of three ivermectin or pyrantel treatments given at intervals of 5 weeks at the beginning of the grazing season. Although each pyrantel treatment resulted in a greater than 95% reduction in faecal egg counts during the first 3 weeks, high pasture larval counts were seen from the beginning of August onwards and substantial cyathostomine burdens were found at necropsy in December. The ivermectin treatments resulted in an even more pronounced reduction in faecal egg output, and the pasture larval counts and cyathostomine burdens at necropsy...
Prescott JF.Recent isolations of Rhodococcus equi from cavitatory pulmonary disease in patients with AIDS have aroused interest among medical microbiologists in this unusual organism. Earlier isolations from humans had also been in immunosuppressed patients following hemolymphatic tumors or renal transplantation. This organism has been recognized for many years as a cause of a serious pyogranulomatous pneumonia of young foals and is occasionally isolated from granulomatous lesions in several other species, in some cases following immunosuppression. The last decade has seen many advances in understanding o...
Alexander CS, Keller H.Over 130 cases of equine periodic ophthalmia (p.o.), which were treated as in-patients at the Equine Clinic of the Free University of Berlin in the last 35 years, were examined statistically in relation to the age and gender of the animals involved as well as to the development of the illness and the season in which it arose. As regards aetiology, the extraction of 71 affected Trotters was investigated. Antibodies to toxoplasmosis, leptospirosis and intestinal parasites were found only in some of the patients. Younger animals, aged between one and four years, and male animals (63.6%) were pred...
Friedhoff KT, Tenter AM, Müller I.The geographical distribution of Babesia equi and Babesia caballi and their tick vectors is discussed. Control of infections with these protozoa is hampered by the lack of a suitable antiprotozoal drug and a reliable serological test. No vaccine is available. Ehrlichia risticii (the causal agent of Potomac horse fever) and E. equi are rickettsial parasites which are difficult to control. Little is known of their geographical distribution and vectors. Early diagnosis is required for tetracycline therapy to be effective and there is a need for a rapid test to provide an early diagnosis.
Mogg TD, Pollitt CC, Willmore JP, Thompson H.Three groups of horses and ponies (N = 13, 13 and 12) were treated with ivermectin paste (0.2 mg/kg p.o.), avermectin B1 solution (0.2 mg/kg p.o.), or fenbendazole suspension (10 mg/kg via nasogastric tube). The avermectin B1 was a 1% solution in a propylene glycolglycerol formal base. Faecal strongyle egg counts were performed before, and 14, 28, 42, 56 and 70 d, after treatment. Full-thickness skin biopsies from the neck, pectoral and umbilical regions were examined for Onchocera microfilaria before treatment, and again 14 and 70 d later. Ivermectin therapy produced a significant (P less tha...
Eysker M, Vercruysse J.The epidemiology, chemotherapy and control of strongylus infections in the horse are discussed. The annual cycle of various species are stated. In addition the anthelmintics available for treatment and control and the occurrence of anthelmintic resistance are referred to. Finally the options for control under various management conditions (little if any grazing; extensive grazing; intensive grazing) are discussed.
Dubey JP, Porterfield ML.Tachyzoites of Neospora caninum were found in sections of lung of an equine fetus aborted 2 mo before term. Individual tachyzoites were approximately 3-5 x 2-3 microns, divided by endodyogeny, and stained positively with anti-N. caninum serum but not with anti-Toxoplasma gondii serum. Toxoplasma gondii antibody was not found in the mare's serum. This is the first report of N. caninum in a horse and indicates that N. caninum can be transmitted transplacentally in equids.
Ahmed JS, Schmid G, Hörchner F.Pony peripheral blood lymphocytes (PBL) were stimulated with a soluble fraction of Trypanosoma (T.) evansi (SF). As determined by 3H-thymidine incorporation, the cells underwent a proliferative response and were able to: a) produce a factor having the biological activities of interleukin 2 (IL-2) since their supernatants could support the in vitro growth of pony PBL stimulated with concanavalin A (Con A-blasts); b) undergo a further proliferative response when incubated in short term cultures with SF, human recombinant IL-2 (hrIL-2), or both c) bind specifically radiolabelled hrIL-2 (125I-hrIL...
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...
Duncan JL, McBeath DG, Preston NK.The efficacy of a fenbendazole divided dose regime against immature stages of Trichonema spp, Strongylus vulgaris and Strongylus edentatus was evaluated. A group of 8 naturally infected 30 to 36-month-old ponies was divided into 2 equal groups on the basis of previous treatment and faecal egg counts, one group being treated with 7.5 mg/kg bwt of fenbendazole daily for 5 days. This treatment regime removed 80 per cent of migrating S vulgaris larvae, 100 per cent of migrating S edentatus larvae and 95 per cent of the mucosal stages of Trichonema spp. In addition, a virtual 100 per cent eliminati...
Coultous RM, Raftery AG, Shiels BR, Sutton DGM, Weir W.Sarcocystis fayeri is a canine protozoan parasite with an equine intermediate host. Historically classified as an incidental pathogen, recent literature has described the toxic effects of Sarcocystis fayeri in human food poisoning, and highlighted potential involvement in equine neuromuscular disease. Until now, horses were believed to be the exclusive intermediate host. This study reports the first molecular confirmation of S. fayeri in a donkey, and gives rise to the consideration of donkeys being a potential reservoir for the parasite. This finding is of particular importance in understandi...
Houston RS, Craig TM, Fincher GT.Effects on the recently introduced dung-burying beetle, Onthophagus gazella F, on free-living stages of equine strongyles were determined on a Texas pasture. Two populations of O gazella (22 and 44 pairs) were exposed to 1-kg deposits of equine dung containing 545,000 strongyle eggs for 31 days near the end of the beetle's activity season. Weekly dung and pasture samples were taken from these plots and from control plots from which beetles were excluded to recover developing larvae. Significant differences did not occur among the 3 treatments (P less than 0.05).
Granstrom DE.This article reviews recent advances in laboratory diagnosis of equine parasitic diseases. Laboratory diagnosis of most equine parasitic diseases continues to rely on standard methods. Only laboratory diagnostic tests for EPM, cryptosporidiosis, and giardiasis were included. The criteria for testing and interpretation of results for each new diagnostic method were explained. Western blot and PCR testing for EPM and immunofluorescent staining with monoclonal antibodies for cryptosporidiosis and giardiasis were reviewed.
Kornaś S, Cabaret J, Nowosad B.Faecal egg counts were performed in 187 foals of a large Polish stud farm between February and September 2007. Eggs of Parascaris equorum were present in faeces of 7% and those of cyathostomins in 13% of the foals aged less than 194 days. Information dealing with age of foals and/or efficiency of ivermectin treatment as well as the nematode parasite prepatent periods, it can be conducted that most of the infections recorded on the basis of faecal egg counts were false-infections in animals up to the age of six months, probably due to the ingestion of infected faeces of their dam or some other ...
Klei TR.This article briefly reviews new information on trichostrongylid stomach worms, spirurid stomach worms, tapeworms, threadworms, pinworms, intestinal protozoa, lungworms, eye worms, and numerous other aberrant parasites as it relates to prevalence, pathogenesis of diseases, and treatments.
Cao X, Vidyashankar AN, Nielsen MK.Decades of intensive anthelmintic treatment has caused equine large strongyles to become quite rare, while the cyathostomins have developed resistance to several drug classes. The larval culture has been associated with low to moderate negative predictive values for detecting Strongylus vulgaris infection. It is unknown whether detection of other large strongyle species can be statistically associated with presence of S. vulgaris. This remains a statistical challenge because of the rare occurrence of large strongyle species. This study used a modified Poisson regression to analyse a dataset fo...
Farahi S, Shishehbor P, Nemati A, Witaliński W.A new mite species, Trachygamasus karuni sp. nov. is described from buffalo, sheep and horse manure at several locations north of Ahvaz city, Khuzestan, Iran. A key to 14 world species of Trachygamasus with described adults is also provided.
Eysker M, Boersema JH, Kooyman FN.Overwintering of horse cyathostomes as inhibited third stage larvae (L3) and the effect of repeated oxfendazole (OFZ) treatment on strongyle infections were studied in an experiment with two groups of three Shetland ponies. Both groups were grazed together from May 28 to November 11, 1986 and subsequently housed. Treatments with 10 mg OFZ kg-1 were given on May 26, July 1 and July 28 and again one week before each group was necropsied in December and April, respectively. Worm populations of both groups were dominated by inhibited early L3. The proportion of fourth stage larvae (L4) was signifi...
Farah Haziqah MT, Nur Hikmah AM, Mat Hasan H, Hamdan A, Nik Him NAII.An investigation was undertaken for screening and isolating nematophagous-fungi from the faecal samples of various grazing animals and soils in Malaysia. Total of 111 faeces and 50 soil samples were collected and the samples were cultured on 2% water agar plates. The growth of nematophagous-fungi was stimulated by sprinkling-baiting technique. The conidia of suspected nematophagous-fungi were inoculated on 2% water agar plates. All isolated were maintained on 2% cornmeal agar plates. Verticillium spp., Fusarium spp. and Arthrobotrys spp. were identified from the faecal and soil samples. 62.5% ...
Beelitz P, Rieder N, Gothe R.In this epidemiological study 30 mares and their foals from seven farms in Upper Bavaria were investigated. Eimeria-leuckarti-oocysts were found in 24 foals (80%), but only in one mare. Oocysts were first detected 28 days post partum at the earliest and 191 days post partum at the latest. In foals, excretion of oocysts usually occurred intermittently with coproscopically negative intervals of up to 15 weeks, and was most frequent in June (8 foals), July (17 foals), and August (10 foals). With the exception of two animals which had mild diarrhoea, the oocyst-shedding foals showed no clinical si...
Dennis VA, Klei TR, Chapman MR.Supernatants generated by stimulation of peripheral blood mononuclear cells (PBMC) from Strongylus vulgaris sensitized or immunized ponies were assayed in vitro for eosinophil chemotactic activity (ECA) using the filter system in blind well chambers. The supernatants from these cultures were chemotactic for eosinophils, but not for neutrophils. Supernates from cultures of unsensitized PBMC stimulated with S. vulgaris antigen were not chemotactic for eosinophils. ECA was first detected in culture supernatants after 1.5 h of incubation and was dependent on both antigen and PBMC concentrations, b...
Adeyefa CA.The precipitin response of the mitogen produced by Strongylus vulgaris arterial larvae was investigated. IgG (T) from the sera of horses naturally infected with S. vulgaris adults and arterial larvae recognised the presence of two antigenic components of the mitogenic fractions. The results obtained seem to confirm that these antigens are immunogenic in stimulating the production of increased levels of IgG(T) in infected animals, and showed that the procedures could be used as immunological tools in the diagnosis of S. vulgaris infection.
Valdez RA, DiPietro JA, Paul AJ, Lock TF, Hungerford LL, Todd KS.The bioequivalence of Strongid C and generic pyrantel tartrate was determined in a controlled study using 30 horses with naturally acquired endoparasitic infections. Three horses were randomly allocated to each of ten replicates based on quantitative nematode and ascarid egg counts and fecal larvae culture results. Horses within each replicate were randomly assigned to one of three treatment groups. Horses in Treatment Group 1 received only oats; horses in Treatment Group 2 received generic pyrantel tartrate pellets (2.65 mg pyrantel tartrate kg-1) mixed with oats; horses in Treatment Group 3 ...
Emmerich IU.In 2019, one novel pharmaceutical agent for horses or food-producing animals was released on the German market: An injection suspension for horses containing chondrogenic-induced equine allogeneic peripheral blood-derived mesenchymal stem cells as the active ingredient (ArtiCell Forte) is now available. Two established veterinary active pharmaceutical ingredients became accessible for additional species: a salicylanilide anthelmintic oxyclozanide (Distocur) for the treatment and control of fascioliasis in sheep as well as a type-I synthetic pyrethroid permethrin (Z-Itch), which now has additio...
Sazmand A, Yavari M, Babaei M, Nourian A, Otranto D.Migration of Ascaris lumbricoides through the papilla of Vater in humans, and entry into the biliary tree, is well-recognised. Ascaris suum and Toxocara vitulorum have been recovered from the liver of swine and buffalo. We necropsied a Persian Kurdish filly at age 6 months, weighing ∼100 kg. Death evidently was caused by oleander (Nerium oleander) intoxication. An 8-cm adult male Parascaris was found at the lobar-left hepatic bile duct junction. We suggest that the nematode entered anteriorly into the hepatic tree, via the duodenum, major duodenal papilla, bile duct, left hepatic duct and f...
DiPietro JA, Todd KS, Lock TF, McPherron TA.The anthelmintic activity of ivermectin was evaluated in 18 female horses with naturally acquired parasitic infections. Horses were treated once (IM) with vehicle only (n = 6), 200 microgram/kg of body weight (n = 6), and 300 microgram/kg (n = 6). Efficacy of both dosages of ivermectin was greater than 99% against Gasterophilus spp, 100% against Trichostrongylus axei, Habronema muscae, H majus, and Draschia megastoma, 98% to 99% against adult cyathostomes, 86% to 97% against 4th-stage cyathostomes, and 100% against adult large strongyles. Although ivermectin was incomplete in its activity agai...
Sutoh M, Saheki Y, Ishitani R, Inui S, Narita M, Hamazaki H, Yokota T.This is the first report on Eimeria leuckarti infection in foals in Japan. Seven Thoroughbred or Angloarabian foals 2 to 7 months of age raised in the Hidaka district, Hokkaido, were infected with E. leuckarti. They died of severe alterations caused by the larval migration of Strongylus vulgaris, and were examined over a period from 1970 to 1973. Protozoa of this species were observed in the small intestine in all the foals. They were found mostly in vacuoles of the cytoplasm of monoclear cells in the lamina propria at or near the tip of villi. Various stages of gametocytes, oocysts, and micro...
Matthews JB, Dowdall SM, Baudena MA, Klei TR, Kaplan RM, von Samson-Himmelstjerna G, Drögemüller M, Schnieder T.This collection of articles provides an in depth account of five presentations delivered during the Symposium on Equine Cyathostomins held at the 19th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP), New Orleans, Louisiana,10–14 August 2003. The symposium was organized and chaired by Ray M. Kaplan and Jacqui B. Matthews and focused on new developments in two major areas of current importance: the immunobiology of cyathostomin–horse interactions and anthelmintic resistance.
Schröder J, Swan GE.Ivermectin, described as 22,23-dihydroavermectin B1, was the compound chosen from the avermectin group of compounds for development as an antiparasitic agent in horses. A review of the literature indicates that parenteral administration in horses at 200 microgram/kg body mass is highly effective against the strongyles Strongylus vulgaris, Strongylus edentatus and triodontophorus spp., and adult and immature cyathostomes, including strains resistant to benzimidazole anthelmintics. Other nematodes controlled in horses include Oxyuris equi, Parascaris equorum, Trichostrongylus axei, and Habronema...
Sokół R, Raś-Noryńska M, Michalczyk M, Raś A, Rapacz-Leonard A, Koziatek S.Studies were carried out in year 2014 during the pasture period (from April to October) in Warmia and Mazury Region. Fecal samples were taken from cold- and warmblood horses from individual and agrotouristic farms with the different housing, feeding and pasture- care practices. Total of 512 horses were examined (320 mares, 170 geldings and 22 stallions). In the group of 185 horses from individual farms, 119 animals (64.3%) were infected with gastro-intestinal parasites. Among the 372 horses from agrotouristic farms 169 (51.7%) were infected with parasites. Most of the animals expelled the eggs...
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...
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...
Salas-Romero J, Gomez-Cabrera K, Molento MB, Lyons ET, Delgado A, González L, Arenal A, Nielsen MK.Equine cyathostomin parasites are ubiquitous in grazing horses and have been shown to cause severe inflammatory disease in the large intestine of horses. Decades of intensive anthelmintic therapy have led to widespread anthelmintic resistance in cyathostomins across the world. In Cuba, no anthelmintic products are formulated and sold for equine usage and little is known about anthelmintic efficacy of ruminant and swine formulations used. A strongyle fecal egg count reduction test was used to assess the efficacy of a liquid formulation of ivermectin labelled for use in swine, ruminants and carn...
Roelfstra L, Betschart B, Pfister K.In a study on the seasonal dynamics of the gastro-intestinal nematode egg production in horses, one breeding farm also revealed a particularly high prevalence of Anoplocephala spp. infection. Consequently, this farm was chosen for analysing the seasonal pattern of the tapeworm egg excretion over a one year period in order to establish the most favourable periods for an appropriate and successful cestocidal treatment. The seasonal analysis showed a significantly higher (p < 0.05) Anoplocephala spp. egg excretion between July and October, i.e. during the second part of the grazing period. This r...
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...
Chiejina SN, Mason JA.Several incidents of diarrhoea and loss of weight occurred in adult horses during the spring of 1976. Detailed investigation of one typical case suggested that maturation of inhibited larvae of Trichonema spp was responsible.
Silvina Fernández A, Henningsen E, Larsen M, Nansen P, Grønvold J, Søndergaard J.An experiment was carried out in 1997 to test the efficacy of an isolate of the microfungus Duddingtonia flagrans against free-living stages of horse strongyles under conditions in the field and to assess the eventual effect of the fungus on the normal degradation of faeces. Faecal pats were made from faeces of a naturally strongyle infected horse, which had been fed fungal material at a dose level of 106 fungal unit/kg bwt. Control pats without fungi were made from faeces collected from the same animal just before being fed fungi. Faecal cultures set up for both groups of faeces to monitor th...
Diyes GCP, Karunaratne WAIP, Tomberlin JK, Rajakaruna RS.Megaselia scalaris (Loew) is a cosmopolitan polyphagous small fly with the ability of exploiting variety of ecological niches. Different life history stages act as detritivore, parasite, and parasitoid of wider spectrum of plant and animal matter under natural and laboratory conditions. Here, for the first time we present the opportunistic parasitism of M. scalaris on Otobius megnini, which act as a vector of Q fever and is capable of causing paralysis, toxic conditions, otoacariasis and otitis in humans and other animals. Tick samples from the ear canals of 14 thoroughbred horses were brought...