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K. Szczepaniak - One of the best experts on this subject based on the ideXlab platform.
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The Strongylidae belonging to Strongylus genus in horses from southeastern Poland
Parasitology Research, 2012Co-Authors: M. B. Studzińska, K. Tomczuk, M. Demkowska-kutrzepa, K. SzczepaniakAbstract:Postmortem parasitic examinations of the large intestines of 725 slaughtered horses from individual farmers in southeastern Poland were carried out. The examinations were carried out monthly since February 2006 until January 2007 (except for August 2007 because of a technological stoppage in the slaughterhouse). The examinations included the intensiveness and extensiveness of the infestation of the Strongylidae belonging to the Strongylus genus. The Strongylidae were found in 26.5 % of the examined horses. Strongylus vulgaris was the most dominant nematode and had a 22.8 % prevalence, Strongylus edentatus was carried by 18.3 % of the horses. Strongylus equinus was identified only in 1.7 % of the examined horses. Our findings revealed that combined infestation of S. vulgaris and S. edentatus occurred in 100 (52.1 %) of the 725 horses infected by the Strongylidae. The present results indicate that the lowest prevalence of strongyle species except for S. equinus was found in January, February, and March. However, it is difficult to draw a conclusion because of an extremely low extensiveness of infestation. The results indicate that the prevalence of the Strongylidae in horses from southeastern Poland is limited.
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REVIEW The Strongylidae belonging to Strongylus genus in horses from southeastern Poland
2012Co-Authors: M. B. Studzińska, K. Tomczuk, M. Demkowska-kutrzepa, K. SzczepaniakAbstract:Abstract Postmortem parasitic examinations of the large intestines of 725 slaughtered horses from individual farmers in southeastern Poland were carried out. The examinations were carried out monthly since February 2006 until January 2007 (except for August 2007 because of a technological stoppage in the slaughterhouse). The examinations included the intensiveness and extensiveness of the infestation of the Strongylidae belonging to the Strongylus genus. The Strongylidae were found in 26.5 % of the examined horses. Strongylus vulgariswas the most dominant nematode and had a 22.8 % prevalence, Strongylus edentatus was carried by 18.3 % of the horses. Strongylus equinus was identified only in 1.7 % of the examined horses. Our findings revealed that combined infestation of S. vulgaris and S. edentatus occurred in 100 (52.1%) of the 725 horses infected by the Strongylidae. The present results indicate that the lowest prevalence of strongyle species except for S. equinus was found in January, February, and March. However, it is difficult to draw a conclusion because of an extremely low extensiveness of infestation. The results indicate that the prevalence of the Strongylidae in horses from southeastern Poland is limited
T. R. Klei - One of the best experts on this subject based on the ideXlab platform.
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Transglutaminase activity in equine strongyles and its potential role in growth and development
EDP Sciences, 2014Co-Authors: U.r. Rao, R.n. Singh, K. Metha, T. R. KleiAbstract:Transglutaminases (E.C. 2.3.3.13) are a family of Ca2+-dependent enzymes that stabilize protein structure by catalyzing the formation of isopeptide bonds. A novel form of transglutaminase has been identified and characterized that seem to play an important role in growth, development, and molting in adult and larval stages of filarial nematodes. The aim of this study was to identify the ubiquitous nature of this enzyme in other nematodes and to measure its significance to larval growth, molting, and development. For this purpose, equine Strongylus spp. were used. Activity of this enzyme was identified in extracts of larvae and adults of Strongylus vulgaris, S. edentatus, Parascaris equorum and Cylicocyclus insigne. The significance of transglutaminase in the early growth and development of Strongylus vulgaris, S. edentatus and S. equinus was tested by adding specific inhibitors, monodansylcadaverine (MDC) or cystamine (CS), to in vitro cultures of third (L3) and fourth stage larvae (L4). The viability, molting and growth of these nematode species were affected by both inhibitors. Cystamine promoted abnormal development of Strongylus edentatus L3, resulting in an aberrant expansion of the anterior end. Addition of these inhibitors to cultures of L4 also reduced growth of the three species. The results indicated that transglutaminase is present in a wide array of nematode parasites and may be important in growth and development of their larval stages
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New method for simultaneous species-specific identification of equine strongyles (nematoda, strongylida) by reverse line blot hybridization
'American Society for Microbiology', 2007Co-Authors: Traversa D, V A Kharchenko, T. R. Klei, Iorio R, Gawor J, Otranto D, Olivier SparaganoAbstract:The ability of a reverse line blot (RLB) assay to identify 13 common species of equine small strongyles (cyathostomins) and to discriminate them from three Strongylus spp. (large strongyles) was demonstrated. The assay relied on the specific hybridization of PCR-amplified intergenic spacer DNA fragments of the nuclear ribosomal DNA to membrane-bound species-specific probes. All cyathostomins examined were unequivocally identified and simultaneously discriminated from each other and from three large strongyles (Strongylus edentatus, Strongylus equinus, and Strongylus vulgaris). This assay will enable the accurate and rapid identification of equine cyathostomins irrespective of their life cycle stage, opening important avenues for a better understanding of their biology and epidemiology and of the pathogenesis of cyathostomin-associated disease. In particular, this RLB method promises to be a powerful diagnostic tool to determine the roles of individual species in the pathogenesis of mixed infections and to elucidate some aspects of cyathostominosis. Also, it could represent a basic step toward the development of a rapid and simple molecular test for the early detection of drug-resistant genotypes of horse strongyle species
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Transglutaminase activity in equine strongyles and its potential role in growth and development.
Parasite (Paris France), 1999Co-Authors: U.r. Rao, M. R. Chapman, R.n. Singh, K. Metha, T. R. KleiAbstract:Les transglutaminases (E.C.2.3.3.13) sont une famille d'enzymes Ca 2+ -dependantes qui stabilisent la structure proteique en catalysant la formation de ponts isopeptidiques. Une forme nouvelle de transglutaminase a ete identifiee et caracterisee; elle semble jouer un role important dans la croissance, le developpement et la mue des stades adultes et larvaires des filaires. L'objectif de cette etude etait d'identifier la nature ubiquitaire de cette enzyme chez d'autres nematodes et d'en mesurer l'impact sur la croissance, la mue et le developpement larvaires. Dans ce but, des especes de Strongylus equines ont ete utilisees. L'activite enzymatique a ete identifiee a partir d'extraits de larves et d'adultes de Strongylus vulgaris, S. edentatus, Parascais equorum et Cylicocyclus insigne. L'impact de la transglutaminase dans la croissance precoce et le developpement de Strongylus vulgaris, S. edentatus et S. equinus a ete teste par l'addition d'inhibiteurs specifiques, monodansylcadaverine (MDC) ou cystamine (CS) aux cultures in vitro de larves de troisieme (L3) et de quatrieme stade (L4). La viabilite, la mue et la croissance de ces especes de nematodes ont ete affectees par les deux inhibiteurs, la cystamine a entraine un developpement anormal des 13 de Strongylus edentatus, se traduisant par une expansion aberrante de l'extremite anterieure. L'addition de ces inhibiteurs aux cultures de 14 a reduit la croissance des trois especes. Ces resultats indiquent que la transglutaminase est presente dans toute une collection de nematodes et peut etre importante pour la croissance et le developpement de leurs stades larvaires.
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Foals raised on pasture with or without daily pyrantel tartrate feed additive: comparison of parasite burdens and host responses following experimental challenge with large and small strongyle larvae.
Veterinary parasitology, 1997Co-Authors: C.m. Monahan, M. R. Chapman, H.w. Taylor, D D French, T. R. KleiAbstract: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 pelleted feed ration. Following this period, all foals were moved into box stalls. Half of each group was challenged with 10(3) Strongylus vulgaris infective third-stage larvae (L3), 5 x 10(3) Strongylus edentatus L3 and 10(5) mixed cyathostome L3; the remaining half served as unchallenged controls. Necropsy examinations were performed 6-week post-challenge for evaluation of parasite burdens and lesions. Daily PT treatment of Group 1 reduced the patent cyathostome infections of both mares and foals and was effective in reducing pasture burdens of infective larvae. Daily treatment of Group 1 foals during weaning continued to suppress EPG levels; however, it did not prevent large strongyle infections during the weaning period. Group 1 foals were more sensitive to challenge than Group 2 foals, which did not exhibit any post-challenge disturbances. Group 1 foals were equally susceptible to challenge as parasite-free foals.
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Production and characterization of monospecific adult worm infections of Strongylus vulgaris and Strongylus edentatus in ponies.
Veterinary parasitology, 1994Co-Authors: J. R. Mcclure, M. R. Chapman, T. R. KleiAbstract:Abstract Since 1978, 20 surgical implantations of either Strongylus vulgaris or Strongylus edentatus have been performed in our laboratory for the purpose of obtaining single species cultures of these parasites. Following surgical implantation peak EPG values of 13–327 ( S. vulgaris ) and 363–1284 ( S. edentatus ) generally occurred during the first 3 weeks post-implantation. Duration of infections was as long as 5 years. Successful outcome of such surgeries appears to be related to the total number of parasites used (⩾ 38) and the ratio of female to male worms implanted (1 : 1 or 2 : 1).
Hyone-myong Eun - One of the best experts on this subject based on the ideXlab platform.
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Anthelmintic efficacies of a tablet formula of ivermectin-praziquantel on horses experimentally infected with three Strongylus species
Parasitology research, 2009Co-Authors: Stéphane Bonneau, Laurence Maynard, Krzysztof Tomczuk, Dawid J. Kok, Hyone-myong EunAbstract:In this blinded randomized and controlled study, the anthelmintic efficacy of a tablet formula of ivermectin–praziquantel was evaluated in horses experimentally infected with three species of Strongylus larvae. Eighteen previously dewormed horses were inoculated on study day 0 with third-stage larvae of Strongylus vulgaris, Strongylus equinus, and Strongylus edentatus. The horses were randomly allocated to three groups (n = 6): test-drug (tablet formula), positive-control (reference gel), and negative-control (placebo tablet). On day 56, the horses were treated once with the respective drugs. On day 95, the horses were sacrificed, and necropsy examinations were performed to assess the status of the parasite burden (L4 and immature L5) and pathological lesions on selected organs and tissues. By the criteria of worm counts, the test-drug and positive-control showed, respectively, 100% and 97.3% anthelmintic efficacies on S. vulgaris, 100% and 81.4% on S. equinus, and equally 100% on S. edentatus. However, the efficacies on S. equinus and S. edentatus should be taken only as face values considering their respective low worm counts in the placebo group. The S. vulgaris-induced arterial lesions were also reduced in the test-drug and positive-control groups with efficacies of 73.9% and 62.9%, respectively. No adverse reactions were observed with either of the drugs. Our data demonstrate that the Equimax tablet formula was as safe and efficacious as the gel formula anthelmintic on large strongyles in horses.
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Anthelmintic efficacies of a tablet formula of ivermectin–praziquantel on horses experimentally infected with three Strongylus species
Parasitology Research, 2009Co-Authors: Stéphane Bonneau, Laurence Maynard, Krzysztof Tomczuk, Dawid Kok, Hyone-myong EunAbstract:In this blinded randomized and controlled study, the anthelmintic efficacy of a tablet formula of ivermectin–praziquantel was evaluated in horses experimentally infected with three species of Strongylus larvae. Eighteen previously dewormed horses were inoculated on study day 0 with third-stage larvae of Strongylus vulgaris , Strongylus equinus , and Strongylus edentatus . The horses were randomly allocated to three groups ( n = 6): test-drug (tablet formula), positive-control (reference gel), and negative-control (placebo tablet). On day 56, the horses were treated once with the respective drugs. On day 95, the horses were sacrificed, and necropsy examinations were performed to assess the status of the parasite burden (L4 and immature L5) and pathological lesions on selected organs and tissues. By the criteria of worm counts, the test-drug and positive-control showed, respectively, 100% and 97.3% anthelmintic efficacies on S. vulgaris , 100% and 81.4% on S. equinus , and equally 100% on S. edentatus . However, the efficacies on S. equinus and S. edentatus should be taken only as face values considering their respective low worm counts in the placebo group. The S. vulgaris -induced arterial lesions were also reduced in the test-drug and positive-control groups with efficacies of 73.9% and 62.9%, respectively. No adverse reactions were observed with either of the drugs. Our data demonstrate that the Equimax tablet formula was as safe and efficacious as the gel formula anthelmintic on large strongyles in horses.
M. R. Chapman - One of the best experts on this subject based on the ideXlab platform.
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Re-evaluation of ivermectin efficacy against equine gastrointestinal parasites.
Veterinary parasitology, 2001Co-Authors: Thomas R. Klei, M. R. Chapman, Dennis D. French, Steffen Rehbein, Martin Visser, W.k Langholff, P HansonAbstract:Abstract Two trials were conducted to confirm the efficacy of ivermectin paste against endoparasites of horses. In these trials, 20 ponies were treated with ivermectin oral paste at 200 mcg kg body weight once on Day 0, and 20 ponies served as unmedicated controls. The animals carried naturally acquired parasite infections as confirmed by pretrial fecal examination. The animals were necropsied for worm recovery on Days 14, 15 or 16. Parasites recovered were identified to species. Horses treated with ivermectin had significantly ( P 99.0% reduction) adult small strongyles ( Coronocyclus spp including C. coronatus , C. labiatus , C. labratus ; Cyathostomum spp including C. catinatum , C. pateratum ; Cylicocyclus spp including C . ashworthi , C. elongatus , C. insigne , C. leptostomum , C. nassatus , C. radiatus ; Cylicodontophorus bicoronatus ; Cylicostephanus spp including C. asymetricus , C. bidentatus , C. calicatus , C. goldi , C. longibursatus , C. minutus ; Gyalocephalus capitatus ; Parapoteriostomum spp including P. euproctus , P. mettami ; Petrovinema poculatum ; Poteriostomum spp including P. imparidentatum , P. ratzii ) and adult large strongyles ( Strongylus edentatus , S. vulgaris ; Triodontophorus spp including T. brevicauda , T. serratus ; Craterostomum acuticaudatum ) than the controls. Ivermectin was also highly effective (94% to >99%, P Gasterophilus intestinalis larvae, Habronema spp., Oxyuris equi , Parascaris equorum . The data from these two trials confirm that ivermectin paste administered to horses orally at 200 mcg kg −1 continues to be highly effective for treatment and control of a broad range of small and large strongyle species as well as other species of gastrointestinal parasites.
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Transglutaminase activity in equine strongyles and its potential role in growth and development.
Parasite (Paris France), 1999Co-Authors: U.r. Rao, M. R. Chapman, R.n. Singh, K. Metha, T. R. KleiAbstract:Les transglutaminases (E.C.2.3.3.13) sont une famille d'enzymes Ca 2+ -dependantes qui stabilisent la structure proteique en catalysant la formation de ponts isopeptidiques. Une forme nouvelle de transglutaminase a ete identifiee et caracterisee; elle semble jouer un role important dans la croissance, le developpement et la mue des stades adultes et larvaires des filaires. L'objectif de cette etude etait d'identifier la nature ubiquitaire de cette enzyme chez d'autres nematodes et d'en mesurer l'impact sur la croissance, la mue et le developpement larvaires. Dans ce but, des especes de Strongylus equines ont ete utilisees. L'activite enzymatique a ete identifiee a partir d'extraits de larves et d'adultes de Strongylus vulgaris, S. edentatus, Parascais equorum et Cylicocyclus insigne. L'impact de la transglutaminase dans la croissance precoce et le developpement de Strongylus vulgaris, S. edentatus et S. equinus a ete teste par l'addition d'inhibiteurs specifiques, monodansylcadaverine (MDC) ou cystamine (CS) aux cultures in vitro de larves de troisieme (L3) et de quatrieme stade (L4). La viabilite, la mue et la croissance de ces especes de nematodes ont ete affectees par les deux inhibiteurs, la cystamine a entraine un developpement anormal des 13 de Strongylus edentatus, se traduisant par une expansion aberrante de l'extremite anterieure. L'addition de ces inhibiteurs aux cultures de 14 a reduit la croissance des trois especes. Ces resultats indiquent que la transglutaminase est presente dans toute une collection de nematodes et peut etre importante pour la croissance et le developpement de leurs stades larvaires.
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Foals raised on pasture with or without daily pyrantel tartrate feed additive: comparison of parasite burdens and host responses following experimental challenge with large and small strongyle larvae.
Veterinary parasitology, 1997Co-Authors: C.m. Monahan, M. R. Chapman, H.w. Taylor, D D French, T. R. KleiAbstract: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 pelleted feed ration. Following this period, all foals were moved into box stalls. Half of each group was challenged with 10(3) Strongylus vulgaris infective third-stage larvae (L3), 5 x 10(3) Strongylus edentatus L3 and 10(5) mixed cyathostome L3; the remaining half served as unchallenged controls. Necropsy examinations were performed 6-week post-challenge for evaluation of parasite burdens and lesions. Daily PT treatment of Group 1 reduced the patent cyathostome infections of both mares and foals and was effective in reducing pasture burdens of infective larvae. Daily treatment of Group 1 foals during weaning continued to suppress EPG levels; however, it did not prevent large strongyle infections during the weaning period. Group 1 foals were more sensitive to challenge than Group 2 foals, which did not exhibit any post-challenge disturbances. Group 1 foals were equally susceptible to challenge as parasite-free foals.
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Comparison of moxidectin oral gel and ivermectin oral paste against a spectrum of internal parasites of ponies with special attention to encysted cyathostome larvae.
Veterinary parasitology, 1996Co-Authors: C.m. Monahan, M. R. Chapman, Dennis D. French, H.w. Taylor, Thomas R. KleiAbstract:Two dosages of moxidectin oral gel were evaluated and compared to a therapeutic dose of ivermectin oral paste in the control of a spectrum of gastrointestinal parasites of ponies naturally infected in southern Louisiana or Mississippi. Thirty-two mixed-breed ponies ranging in age from one to 21 years were used in this controlled test. Eight weeks prior to the experiment, ponies grazing on contaminated pasture were moved to a paddock and fed a pelleted ration, thus reducing or eliminating the potential for additional infection and ensuring the existence of a population of encysted larvae. Ponies were then allocated to replicates of four animals based on values of fecal strongyle egg counts and percent strongyle larvae composition determined from Baermann sedimentations of fecal cultures. Members of replicates were allocated to one of four treatment groups: moxidectin oral gel administered at 300 micrograms kg-1 body weight, moxidectin oral gel at 400 micrograms kg-1, the oral gel vehicle as negative control, and ivermectin oral paste at 200 micrograms kg-1. Prior to treatment, ponies were confined in pairs to covered concrete runs by treatment group. Two weeks following treatment, necropsy examinations of all animals were performed. Parasites were recovered from the lumen of the stomach, the intestinal tract, the cranial mesenteric artery and its major branches, the peritoneal body wall and from pepsin digests of mucosal scrapings taken from the cecum and large colon. Encysted cyathostome larval burdens were also compared using mural transillumination of segments of the large colon for visualization of the encysted forms. Control ponies were not uniformly infected with the spectrum of parasites; however, moxidectin, at either dosage, compared favorably with ivermectin in the control of the adults of Strongylus vulgaris, Strongylus edentatus, Triodontophorus spp., Oesophagodontus robustus, TrichoStrongylus axei, Oxyuris equi, Parascaris equorum, Habronema muscae, as well as both the adult and larval Cyathostominae recovered from the lumen. Moxidectin also appears as efficacious as ivermectin against migrating large strongyle larvae at the two weeks post-treatment evaluation. Moxidectin demonstrated a trend towards greater efficacy against encysted cyathostome larvae than a therapeutic dosage of ivermectin, but this difference was not statistically significant. Moxidectin was less effective than ivermectin against Gasterophilus intestinalis and was equally ineffective as ivermectin against Anoplocephala perfoliata.
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Dose titration of moxidectin oral gel against gastrointestinal parasites of ponies.
Veterinary parasitology, 1995Co-Authors: C.m. Monahan, M. R. Chapman, Dennis D. French, H.w. Taylor, Thomas R. KleiAbstract:Abstract Moxidectin was tested as an oral gel formulation during a controlled test performed to evaluate dosages against equine gastrointestinal parasites. Four groups of ten ponies were used. Ponies ranged from 1 to 20 years of age and were naturally infected in southern Louisiana or Mississippi. Fecal exams and fecal cultures were performed on all ponies to determine the strongyle egg counts and the percent distributions of large and small strongyles. Following these determinations, ponies were allocated to replicates of four ponies to provide an even distribution of strongyle infection, age, weight and gender. Members of each replicate were then randomly assigned to one of four treatment groups. The doses tested were 300, 400 and 500 μg kg −1 body weight. The oral gel vehicle alone served as control. Treatments were administered behind the tongue and the ponies were observed continuously for 4 h for any adverse reactions; thereafter, ponies were observed at least twice daily. Necropsy examinations were performed 14 days post-treatment for the recovery and identification of any parasites present. Moxidectin, at all doses tested, was 100% efficacious against adults of Strongylus vulgaris, Strongylus edentatus, Triodontophorus spp. and 22 species of small strongyles. Moxidectin was also 100% efficacious against larvae of Strongylus edentatus and Oxyuris equi , greater than 94% efficacious against Strongylus vulgaris larvae and Oxyuris equi adults at 14 days post-treatment. Moxidectin proved highly efficacious against luminal small strongyle larvae (>99.9% against L 4 and >92% against L 3 ) and moxidectin demonstrated some efficacy against encysted small strongyle larvae as well. Although control ponies were not uniformly infected with Habronema muscae, TrichoStrongylus axei and Parascaris equorum , none of these parasites were recovered from moxidectin-treated ponies, suggesting high efficacy against these species as well. Efficacy against Gasterophilus spp. was 89%, 96% and 97% in a dose-dependent fashion. Moxidectin had no demonstrable activity against Anoplocephala perfoliata .
Thomas R. Klei - One of the best experts on this subject based on the ideXlab platform.
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New Method for Simultaneous Species-Specific Identification of Equine Strongyles (Nematoda, Strongylida) by Reverse Line Blot Hybridization
Journal of clinical microbiology, 2007Co-Authors: Donato Traversa, Thomas R. Klei, V A Kharchenko, Raffaella Iorio, Jakub Gawor, Domenico Otranto, Olivier SparaganoAbstract:The ability of a reverse line blot (RLB) assay to identify 13 common species of equine small strongyles (cyathostomins) and to discriminate them from three Strongylus spp. (large strongyles) was demonstrated. The assay relied on the specific hybridization of PCR-amplified intergenic spacer DNA fragments of the nuclear ribosomal DNA to membrane-bound species-specific probes. All cyathostomins examined were unequivocally identified and simultaneously discriminated from each other and from three large strongyles (Strongylus edentatus, Strongylus equinus, and Strongylus vulgaris). This assay will enable the accurate and rapid identification of equine cyathostomins irrespective of their life cycle stage, opening important avenues for a better understanding of their biology and epidemiology and of the pathogenesis of cyathostomin-associated disease. In particular, this RLB method promises to be a powerful diagnostic tool to determine the roles of individual species in the pathogenesis of mixed infections and to elucidate some aspects of cyathostominosis. Also, it could represent a basic step toward the development of a rapid and simple molecular test for the early detection of drug-resistant genotypes of horse strongyle species.
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Purification and analyses of the specificity of two putative diagnostic antigens for larval cyathostomin infection in horses.
Research in veterinary science, 2003Co-Authors: Samantha M.j. Dowdall, Thomas R. Klei, Christopher J. Proudman, Sandy Love, J. B. MatthewsAbstract: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 specific to larval cyathostomins. No cross-reactive antigens appeared to be present in Parascaris equorum or Strongyloides westeri species. Low levels of cross-reactivity were observed in Strongylus edentatus and Strongylus vulgaris species. Use of purified antigens greatly reduced background binding in equine sera. These results indicate that both antigen complexes may be of use in a diagnostic assay.
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Re-evaluation of ivermectin efficacy against equine gastrointestinal parasites.
Veterinary parasitology, 2001Co-Authors: Thomas R. Klei, M. R. Chapman, Dennis D. French, Steffen Rehbein, Martin Visser, W.k Langholff, P HansonAbstract:Abstract Two trials were conducted to confirm the efficacy of ivermectin paste against endoparasites of horses. In these trials, 20 ponies were treated with ivermectin oral paste at 200 mcg kg body weight once on Day 0, and 20 ponies served as unmedicated controls. The animals carried naturally acquired parasite infections as confirmed by pretrial fecal examination. The animals were necropsied for worm recovery on Days 14, 15 or 16. Parasites recovered were identified to species. Horses treated with ivermectin had significantly ( P 99.0% reduction) adult small strongyles ( Coronocyclus spp including C. coronatus , C. labiatus , C. labratus ; Cyathostomum spp including C. catinatum , C. pateratum ; Cylicocyclus spp including C . ashworthi , C. elongatus , C. insigne , C. leptostomum , C. nassatus , C. radiatus ; Cylicodontophorus bicoronatus ; Cylicostephanus spp including C. asymetricus , C. bidentatus , C. calicatus , C. goldi , C. longibursatus , C. minutus ; Gyalocephalus capitatus ; Parapoteriostomum spp including P. euproctus , P. mettami ; Petrovinema poculatum ; Poteriostomum spp including P. imparidentatum , P. ratzii ) and adult large strongyles ( Strongylus edentatus , S. vulgaris ; Triodontophorus spp including T. brevicauda , T. serratus ; Craterostomum acuticaudatum ) than the controls. Ivermectin was also highly effective (94% to >99%, P Gasterophilus intestinalis larvae, Habronema spp., Oxyuris equi , Parascaris equorum . The data from these two trials confirm that ivermectin paste administered to horses orally at 200 mcg kg −1 continues to be highly effective for treatment and control of a broad range of small and large strongyle species as well as other species of gastrointestinal parasites.
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Comparison of moxidectin oral gel and ivermectin oral paste against a spectrum of internal parasites of ponies with special attention to encysted cyathostome larvae.
Veterinary parasitology, 1996Co-Authors: C.m. Monahan, M. R. Chapman, Dennis D. French, H.w. Taylor, Thomas R. KleiAbstract:Two dosages of moxidectin oral gel were evaluated and compared to a therapeutic dose of ivermectin oral paste in the control of a spectrum of gastrointestinal parasites of ponies naturally infected in southern Louisiana or Mississippi. Thirty-two mixed-breed ponies ranging in age from one to 21 years were used in this controlled test. Eight weeks prior to the experiment, ponies grazing on contaminated pasture were moved to a paddock and fed a pelleted ration, thus reducing or eliminating the potential for additional infection and ensuring the existence of a population of encysted larvae. Ponies were then allocated to replicates of four animals based on values of fecal strongyle egg counts and percent strongyle larvae composition determined from Baermann sedimentations of fecal cultures. Members of replicates were allocated to one of four treatment groups: moxidectin oral gel administered at 300 micrograms kg-1 body weight, moxidectin oral gel at 400 micrograms kg-1, the oral gel vehicle as negative control, and ivermectin oral paste at 200 micrograms kg-1. Prior to treatment, ponies were confined in pairs to covered concrete runs by treatment group. Two weeks following treatment, necropsy examinations of all animals were performed. Parasites were recovered from the lumen of the stomach, the intestinal tract, the cranial mesenteric artery and its major branches, the peritoneal body wall and from pepsin digests of mucosal scrapings taken from the cecum and large colon. Encysted cyathostome larval burdens were also compared using mural transillumination of segments of the large colon for visualization of the encysted forms. Control ponies were not uniformly infected with the spectrum of parasites; however, moxidectin, at either dosage, compared favorably with ivermectin in the control of the adults of Strongylus vulgaris, Strongylus edentatus, Triodontophorus spp., Oesophagodontus robustus, TrichoStrongylus axei, Oxyuris equi, Parascaris equorum, Habronema muscae, as well as both the adult and larval Cyathostominae recovered from the lumen. Moxidectin also appears as efficacious as ivermectin against migrating large strongyle larvae at the two weeks post-treatment evaluation. Moxidectin demonstrated a trend towards greater efficacy against encysted cyathostome larvae than a therapeutic dosage of ivermectin, but this difference was not statistically significant. Moxidectin was less effective than ivermectin against Gasterophilus intestinalis and was equally ineffective as ivermectin against Anoplocephala perfoliata.
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Dose titration of moxidectin oral gel against gastrointestinal parasites of ponies.
Veterinary parasitology, 1995Co-Authors: C.m. Monahan, M. R. Chapman, Dennis D. French, H.w. Taylor, Thomas R. KleiAbstract:Abstract Moxidectin was tested as an oral gel formulation during a controlled test performed to evaluate dosages against equine gastrointestinal parasites. Four groups of ten ponies were used. Ponies ranged from 1 to 20 years of age and were naturally infected in southern Louisiana or Mississippi. Fecal exams and fecal cultures were performed on all ponies to determine the strongyle egg counts and the percent distributions of large and small strongyles. Following these determinations, ponies were allocated to replicates of four ponies to provide an even distribution of strongyle infection, age, weight and gender. Members of each replicate were then randomly assigned to one of four treatment groups. The doses tested were 300, 400 and 500 μg kg −1 body weight. The oral gel vehicle alone served as control. Treatments were administered behind the tongue and the ponies were observed continuously for 4 h for any adverse reactions; thereafter, ponies were observed at least twice daily. Necropsy examinations were performed 14 days post-treatment for the recovery and identification of any parasites present. Moxidectin, at all doses tested, was 100% efficacious against adults of Strongylus vulgaris, Strongylus edentatus, Triodontophorus spp. and 22 species of small strongyles. Moxidectin was also 100% efficacious against larvae of Strongylus edentatus and Oxyuris equi , greater than 94% efficacious against Strongylus vulgaris larvae and Oxyuris equi adults at 14 days post-treatment. Moxidectin proved highly efficacious against luminal small strongyle larvae (>99.9% against L 4 and >92% against L 3 ) and moxidectin demonstrated some efficacy against encysted small strongyle larvae as well. Although control ponies were not uniformly infected with Habronema muscae, TrichoStrongylus axei and Parascaris equorum , none of these parasites were recovered from moxidectin-treated ponies, suggesting high efficacy against these species as well. Efficacy against Gasterophilus spp. was 89%, 96% and 97% in a dose-dependent fashion. Moxidectin had no demonstrable activity against Anoplocephala perfoliata .
