FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Animals (Basel) / Parasites in Horses Kept in A 2.5 Year-Round Grazing System ...
Animals : an open access journal from MDPI2019; 9(12); doi: 10.3390/ani9121156

Parasites in Horses Kept in A 2.5 Year-Round Grazing System in Nordic Conditions without Supplementary Feeding.

Abstract: Horse grazing can be favorable from a biological diversity perspective. This study documented the occurrence of endo- and ectoparasites and sought to reduce parasite egg excretion with the anthelmintic drug pyrantel in 12 Gotlandsruss stallions maintained in a year-round grazing system for 2.5 years. Feces samples were collected monthly and all horses were treated with pyrantel, the anthelmintic drug of choice in biological diversity preservation, at study population mean cyathostomin eggs per gram (EPG) of >200. The relationship between cyathostomin EPG and body condition was studied, as was horse behavioral response to Bovicola equi (chewing louse) infestation. Eggs of cyathostomins (small strongyles), Parascaris spp. (roundworm), Oxyuris equi (pinworm), Anoplocephala perfoliata (tapeworm), and Gasterophilus spp. (botfly) were detected at least once during the trial. Excretion of cyathostomin eggs was highest during summer-autumn and increased year-on-year. No relationship was found between cyathostomin EPG and body condition. Infestation with B. equi did not affect the number of scratching sessions compared with unaffected horses. Therefore, in this year-round grazing system, pyrantel treatment had to be complemented with moxidectin to reduce excretion of cyathostomin eggs, thus compromising biological diversity.
Get Full Text
Publication Date: 2019-12-17 PubMed ID: 31861066PubMed Central: PMC6940839DOI: 10.3390/ani9121156Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
LinkedInCopy
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This study investigates the occurrence of parasites in grazing horses and the effects of a particular type of drug treatment. The research found that despite the drug treatment, parasite egg excretion increased overtime, implying additional treatments may be necessary.

Objective of the Study

  • The main purpose of this research was to document the occurrence of both internal and external parasites in horses that were kept in a year-round grazing system over 2.5 years, without any supplementary feeding.
  • Another objective of the research was to understand the effect of pyrantel, an anthelmintic drug (a medication that expels parasitic worms), in controlling the excretion of parasite eggs.

Methods

  • The researchers collected feces samples from 12 stallions belonging to the Gotlandsruss breed on a monthly basis.
  • All the horses included in the study were treated with pyrantel whenever the study population mean cyathostomin eggs per gram (EPG) was more than 200.
  • The paper examined the relationship between cyathostomin EPG and the body condition of the horses, as well as the horse’s behavioral response to a particular louse infestation.

Findings

  • The eggs of five different types of parasites, namely cyathostomins (small strongyles), roundworms, pinworms, tapeworms, and botflies were found in at least one of the collected samples during the trial period.
  • The study found that the excretion of cyathostomin eggs was at its peak during the summer-autumn season and increased year-by-year.
  • Interestingly, no relationship was established between cyathostomin EPG and the body condition of the horses.
  • The study also discovered that infestation with a specific variety of louse did not lead to a change in the number of scratching sessions compared to unaffected horses.

Implications

  • The use of pyrantel alone was not successful in reducing the excretion of cyathostomin eggs in the year-round grazing system used in this study.
  • As a result, another anthelmintic drug, moxidectin, had to be used alongside pyrantel to reduce the excretion, a move that may potentially compromise biological diversity.

Cite This Article

APA
Tydén E, Jansson A, Ringmark S. (2019). Parasites in Horses Kept in A 2.5 Year-Round Grazing System in Nordic Conditions without Supplementary Feeding. Animals (Basel), 9(12). https://doi.org/10.3390/ani9121156

Publication

Animals : an open access journal from MDPI
ISSN: 2076-2615
NlmUniqueID: 101635614
Country: Switzerland
Language: English
Volume: 9
Issue: 12

Researcher Affiliations

Tydén, Eva
  • Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden.
Jansson, Anna
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden.
Ringmark, Sara
  • Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, SE-75007 Uppsala, Sweden.

Grant Funding

  • no / WWF Sweden
  • no / Helge Ax:on Johnsson Foundation
  • no / Swedish University of Agricultural Sciences
  • no / crowd-funding

Conflict of Interest Statement

The authors declare no conflict of interest. The funders played no role in the design of the study; in the collection, analyses, or interpretation of data; in writing the manuscript; or in the decision to publish the results.

References

This article includes 46 references
  1. Gärdenfors U, Simán S, Lundkvist K. Rödlistade Arter i Sverige 2005. ArtDatabanken i Samarbete Med Naturvårdsverket; Uppsala, Sweden: 2005.
  2. Garrido P, Mårell A, Öckinger E, Skarin A, Jansson A, Thulin CG. Experimental rewilding enhances grassland functional composition and pollinator habitat use. J. Appl. Ecol. 2019;56:946–955.
    doi: 10.1111/1365-2664.13338google scholar: lookup
  3. Swedish Veterinary Institute, Uppsala, Sweden. [(accessed on 4 November 2019)];2019 Available online: https://www.sva.se/djurhalsa/hast/parasiter-hos-hast.
  4. Back H, Nyman A, Osterman Lind E. The association between Anoplocephala perfoliata and colic in Swedish horses-a case control study. Vet. Parasitol. 2013;197:580–585.
    doi: 10.1016/j.vetpar.2013.07.020pubmed: 23993633google scholar: lookup
  5. Nielsen M, Mittel L, Grice A, Erskine M, Graves E, Vaala W, Tully R, French D, Bowman R, Kaplan R. AAEP Parasite Control Guidelines. American Association of Equine Practitioners; Lexington, KY, USA: 2016.
  6. Clayton HM, Duncan JL. The migration and development of Parascaris equorum in the horse. Int. J. Parasitol. 1979;9:285–292.
    doi: 10.1016/0020-7519(79)90076-6pubmed: 489235google scholar: lookup
  7. Love S, Murphy D, Mellor D. Pathogenicity of cyathostome infection. Vet. Parasitol. 1999;85:113–122.
    doi: 10.1016/S0304-4017(99)00092-8pubmed: 10485358google scholar: lookup
  8. Matthews JB. Anthelmintic resistance in equine nematodes. Int. J. Parasitol. 2014;4:310–315.
    doi: 10.1016/j.ijpddr.2014.10.003pmc: PMC4266799pubmed: 25516842google scholar: lookup
  9. Osterman Lind E, Kuzmina T, Uggla A, Waller PJ, Höglund J. A Field Study on the Effect of Some Anthelmintics on Cyathostomins of Horses in Sweden. Vet. Res. Commun. 2007;31:53–65.
    doi: 10.1007/s11259-006-3402-5pubmed: 17186406google scholar: lookup
  10. Höglund J, Ljungström B, Gustafsson K. Sviktande effekt av Pyratel. Sven. Veterinärtidning 2011;6:19–21.
  11. Martin F, Höglund J, Bergström TF, Karlsson Lindsjö O, Tydén E. Resistance to pyrantel embonate and efficacy of fenbendazole in Parascaris univalens on Swedish stud farms. Vet. Parasitol. 2018;264:69–73.
    doi: 10.1016/j.vetpar.2018.11.003pubmed: 30503095google scholar: lookup
  12. Beynon SA. Potential environmental consequences of administration of anthelmintics to sheep. Vet. Parasitol. 2012;189:113–124.
    doi: 10.1016/j.vetpar.2012.03.040pubmed: 22538093google scholar: lookup
  13. Mesa LM, Horler J, Lindt I, Gutierrez MF, Negro L, Mayora G, Montalto L, Ballent M, Lifschitz A. Effects of the antiparasitic drug moxidectin in cattle dung on zooplankton and benthic invertebrates and its accumulation in a water-sediment system. Arch. Environ. Contam. Toxicol. 2018;75:316–326.
    doi: 10.1007/s00244-018-0539-5pubmed: 29846763google scholar: lookup
  14. Klei TR, Chapman MR. Immunity in equine cyathostome infections. Vet. Parasitol. 1999;85:123–133.
    doi: 10.1016/S0304-4017(99)00093-Xpubmed: 10485359google scholar: lookup
  15. Fleurance G, Duncan P, Fritz H, Cabaret J, Cortet J, Gordon IJ. Selection of feeding sites by horses at pasture: Testing the anti-parasite theory. Appl. Anim. Behav. Sci. 2007;108:288–301.
    doi: 10.1016/j.applanim.2006.11.019google scholar: lookup
  16. Henneke DR, Potter GD, Kreider JL, Yeates BF. Relationship between condition score, physical measurements and body-fat percentage in mares. Equine Vet. J. 1983;15:371–372.
    doi: 10.1111/j.2042-3306.1983.tb01826.xpubmed: 6641685google scholar: lookup
  17. Coles GC, Bauer C, Borgsteede FH, Geerts S, Klei TR, Taylor MA, Waller PJ. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) methods for the detection of anthelmintic resistance in nematodes of veterinary importance. Vet. Parasitol. 1992;44:35–44.
    doi: 10.1016/0304-4017(92)90141-Upubmed: 1441190google scholar: lookup
  18. Bellaw JL, Nielsen MK. Evaluation of Baermann apparatus sedimentation time on recovery of Strongylus vulgaris and S. edentatus third stage larvae from equine coprocultures. Vet. Parasitol. 2015;211:99–101.
    doi: 10.1016/j.vetpar.2015.05.001pubmed: 25976635google scholar: lookup
  19. Van Wyk JA, Mayhew E. Morphological identification of parasitic nematode infective larvae of small ruminants and cattle: A practical lab guide. Onderstepoort J. Vet. Res. 2013;80:539.
    doi: 10.4102/ojvr.v80i1.539pubmed: 23718204google scholar: lookup
  20. Russel A. The development of helminthiasis in thoroughbred foals. J. Comp. Pathol. Ther. 1948;58:107–127.
    doi: 10.1016/S0368-1742(48)80009-3pubmed: 18861669google scholar: lookup
  21. Beroza GA, Marcus LC, Williams R, Bauer SM. Laboratory diagnosis of Anoplocephala perfoliata infection in horses. Proc. Am. Assoc. Equine Pract. 1987;32:435–439.
  22. FASS djurläkemedel, Sweden. [(accessed on 21 November 2019)];2019 Available online: https://www.fass.se/LIF/startpage?userType=1.
  23. Ogbourne CP. Epidemiological studies on horses infected with nematodes of the family Trichonematidae (Witenberg, 1925). Int. J. Parasitol. 1975;5:667–672.
    doi: 10.1016/0020-7519(75)90067-3pubmed: 1201900google scholar: lookup
  24. Eysker M, Boersema J, Kooyman F. Seasonally inhibited development of cyathostomine nematodes in Shetland ponies in The Netherlands. Vet. Parasitol. 1990;36:259–264.
    doi: 10.1016/0304-4017(90)90037-Cpubmed: 2399646google scholar: lookup
  25. Nielsen MK, Kaplan RM, Thamsborg SM, Monrad J, Olsen SN. Climatic influences on development and survival of free-living stages of equine strongyles: Implications for worm control strategies and managing anthelmintic resistance. Vet. J. 2007;174:23–32.
    doi: 10.1016/j.tvjl.2006.05.009pubmed: 16815051google scholar: lookup
  26. Ringmark S, Skarin A, Jansson A. Impact of year-round grazing by horses on pasture nutrient dynamics and the correlation with pasture nutrient content and fecal nutrient composition. Animals 2019;9:500.
    doi: 10.3390/ani9080500pmc: PMC6720502pubmed: 31362460google scholar: lookup
  27. Swedish Meteorological and Hydrological Institute (SMHI) 2018 Weather Station Uppsala Aut. [(accessed on 10 April 2018)]; Available online: https://www.smhi.se/klimatdata.
  28. Mfitilodze M, Hutchinson G. Development and survival of free-living stages of equine strongyles under laboratory conditions. Vet. Parasitol. 1987;23:121–133.
    doi: 10.1016/0304-4017(87)90030-6pubmed: 3564339google scholar: lookup
  29. Kuzmina TA, Dzeverin I, Kharchenko VA. Strongylids in domestic horses: Influence of horse age, breed and deworming programs on the strongyle parasite community. Vet. Parasitol. 2016;227:56–63.
    doi: 10.1016/j.vetpar.2016.07.024pubmed: 27523938google scholar: lookup
  30. Reinemeyer C, Nielsen M. Review of the biology and control of O xyuris equi. Equine Vet. Educ. 2014;26:584–591.
    doi: 10.1111/eve.12218google scholar: lookup
  31. Urquhart GM, Armour J, Duncan JL, Dunn AM, Jennings FW. Veterinary Parasitology. 2nd ed. Blackwell Sciences; London, UK: 1996. p. 307.
  32. Denegri GM. Review of oribatid mites as intermediate hosts of tapeworms of the Anoplocephalidae. Exp. Appl. Acarol. 1993;17:567–580.
    doi: 10.1007/BF00053486google scholar: lookup
  33. Mencke N, Larsen KS, Eydal M, Sigurðsson H. Dermatological and parasitological evaluation of infestations with chewing lice (Werneckiella equi) on horses and treatment using imidacloprid. Parasitol. Res. 2005;97:7–12.
    doi: 10.1007/s00436-005-1379-6pubmed: 15940520google scholar: lookup
  34. James P, Moon RD, Brown D. Seasonal dynamics and variation among sheep in densities of the sheep biting louse, Bovicola ovis. Int. J. Parasitol. 1998;28:283–292.
    doi: 10.1016/S0020-7519(97)00188-4pubmed: 9512991google scholar: lookup
  35. James PJ. Do sheep regulate the size of their mallophagan louse populations?. Int. J. Parasitol. 1999;29:869–875.
    doi: 10.1016/S0020-7519(99)00055-7pubmed: 10480724google scholar: lookup
  36. Sweeney H. The prevalence and pathogenicity of Gasterophilus intestinalis larvae in horses in Ireland. Ir. Vet. J. 1990;43:67–73.
  37. Jenkins E, Backwell AL, Liboiron A, Colpitts J, Tollett C, Medill S, Bellaw J, Shury T, McRuer D, Gilleard J. Gastrointestinal and respiratory nematodes in feral horses of Sable Island–a living experiment in equine parasite epidemiology. Proceedings of the World Association for the Advancement of Veterinary Parasitology; Madison, WI, USA. 7–11 July 2019.
  38. Peachey LE, Castro C, Molena RA, Jenkins TP, Griffin JL, Cantacessi C. Dysbiosis associated with acute helminth infections in herbivorous youngstock-observations and implications. Sci. Rep. 2019;9.
    doi: 10.1038/s41598-019-47204-6pmc: PMC6668452pubmed: 31366962google scholar: lookup
  39. Debeffe L, McLoughlin PD, Medill SA, Stewart K, Andres D, Shury T, Wagner B, Jenkins E, Gilleard JS, Poissant J. Negative covariance between parasite load and body condition in a population of feral horses. Parasitology 2016;143:983–997.
    doi: 10.1017/S0031182016000408pubmed: 27046508google scholar: lookup
  40. Ringmark S, Revold T, Jansson A. Effects of training distance on feed intake, growth, body condition and muscle glycogen content in young Standardbred horses fed a forage-only diet. Animal 2017;11:1718–1726.
    doi: 10.1017/S1751731117000593pubmed: 28367770google scholar: lookup
  41. Fonseca RG, Kenny DA, Hill EW, Katz LM. The relationship between body composition, training and race performance in a group of Thoroughbred flat racehorses. Equine Vet. J. 2013;45:552–557.
    doi: 10.1111/evj.12024pubmed: 23294231google scholar: lookup
  42. Gold S, Regan CE, McLoughlin PD, Gilleard JS, Wilson AJ, Poissant J. Quantitative genetics of gastrointestinal strongyle burden and associated body condition in feral horses. Int. J. Parasitol. Parasites Wildl. 2019;9:104–111.
    doi: 10.1016/j.ijppaw.2019.03.010pmc: PMC6462499pubmed: 31011533google scholar: lookup
  43. Warburton EM, Pearl CA, Vonhof MJ. Relationships between host body condition and immunocompetence, not host sex, best predict parasite burden in a bat-helminth system. Parasitol. Res. 2016;115:2155–2164.
    doi: 10.1007/s00436-016-4957-xpubmed: 26898834google scholar: lookup
  44. Houston AI, McNamara JM, Barta Z, Klasing KC. The effect of energy reserves and food availability on optimal immune defence. Proc. R. Soc. B Biol. Sci. 2007;274:2835–2842.
    doi: 10.1098/rspb.2007.0934pmc: PMC2373797pubmed: 17848371google scholar: lookup
  45. Naundrup PJ, Svenning J-C. A Geographic Assessment of the Global Scope for Rewilding with Wild-Living Horses (Equus ferus). PLoS ONE 2015;10:e0132359.
    doi: 10.1371/journal.pone.0132359pmc: PMC4503665pubmed: 26177104google scholar: lookup
  46. Sanusi AO, Peters SO, Sonibare AO, Imumorin IG, Ozoje MO. Preliminary association of coat colour types and tolerance to Haemonchus contortus infection in West African Dwarf sheep. J. Appl. Anim. Res. 2012;40:1–7.
    doi: 10.1080/09712119.2011.634178google scholar: lookup

Citations

This article has been cited 9 times.
  1. Klass LG, Krücken J, Mbedi S, Sparmann S, Schenk T, Andreotti S, von Samson-Himmelstjerna G. Characterizing mixed strongyle infections in foals and broodmares using cytochrome c oxidase subunit I deep amplicon sequencing. Parasit Vectors 2026 Jan 3;19(1):65.
    doi: 10.1186/s13071-025-07192-1pubmed: 41484633google scholar: lookup
  2. Thulin CG, Chen Y, Garrido P. Semi-Feral Horse Grazing Benefits the Grassland Diversity of Flowering Plants Including a Pollinator-Promoting Indicator Species. Animals (Basel) 2025 Mar 17;15(6).
    doi: 10.3390/ani15060862pubmed: 40150391google scholar: lookup
  3. Lovász L, Sommer-Trembo C, Barth JMI, Scasta JD, Grancharova-Hill R, Lemoine RT, Kerekes V, Merckling L, Bouskila A, Svenning JC, Fages A. Rewilded horses in European nature conservation - a genetics, ethics, and welfare perspective. Biol Rev Camb Philos Soc 2025 Feb;100(1):407-427.
    doi: 10.1111/brv.13146pubmed: 39279124google scholar: lookup
  4. Viksten SM, Hartmann E, Schneller K, Steen M. Welfare of extensively managed Swedish Gotland ponies. Anim Welf 2023;32:e21.
    doi: 10.1017/awf.2023.20pubmed: 38487419google scholar: lookup
  5. Matthews JB, Peczak N, Lightbody KL. The Use of Innovative Diagnostics to Inform Sustainable Control of Equine Helminth Infections. Pathogens 2023 Oct 11;12(10).
    doi: 10.3390/pathogens12101233pubmed: 37887749google scholar: lookup
  6. Boelow H, Krücken J, von Samson-Himmelstjerna G. Epidemiological study on factors influencing the occurrence of helminth eggs in horses in Germany based on sent-in diagnostic samples. Parasitol Res 2023 Mar;122(3):749-767.
    doi: 10.1007/s00436-022-07765-4pubmed: 36627515google scholar: lookup
  7. Steuer AE, Anderson HP, Shepherd T, Clark M, Scare JA, Gravatte HS, Nielsen MK. Parasite dynamics in untreated horses through one calendar year. Parasit Vectors 2022 Feb 8;15(1):50.
    doi: 10.1186/s13071-022-05168-zpubmed: 35135605google scholar: lookup
  8. Alavi SE, Ebrahimi Shahmabadi H. Anthelmintics for drug repurposing: Opportunities and challenges. Saudi Pharm J 2021 May;29(5):434-445.
    doi: 10.1016/j.jsps.2021.04.004pubmed: 34135669google scholar: lookup
  9. Garrido P, Edenius L, Mikusiński G, Skarin A, Jansson A, Thulin CG. Experimental rewilding may restore abandoned wood-pastures if policy allows. Ambio 2021 Jan;50(1):101-112.
    doi: 10.1007/s13280-020-01320-0pubmed: 32152907google scholar: lookup
Subscribe to our newsletter
Join 99,383 horse owners like you who receive our email updates on horse health and nutrition.