The Use of Molecular Profiling to Track Equine Reinfection Rates of Cyathostomin Species Following Anthelmintic Administration.
Abstract: Cyathostomins are a multispecies parasite ubiquitous in Equids. Cyathostomins have developed resistance to all but one class of anthelmintics, but species-level sensitivity to anthelmintics has not been shown. This study measured reinfection rates of cyathostomin species following the administration of three commercial dewormers. Nine treated horses were compared with 90 untreated controls during June-September 2017-2019. Ivermectin (IVM) (n = 6), Moxidectin (MOX) (n = 8) or Pyrantel (PYR) (n = 8) were orally administered. Fecal samples were collected every 14 d for 98 d. Fecal egg count reductions (FECR) were calculated using a modified McMaster technique. Nineteen cyathostomin species were identified by 5.8S-ITS-2 profiling using amplicon sequencing. Data were analyzed in QIIME1 and R statistical software using presence/absence methods. MOX had the lowest numbers of species present over the time course, followed by PYR then IVM (7.14, 10.17, 11.09, respectively); however, FECR was fastest for PYR. The presence of seven species: and were unaffected by treatment ( > 0.05) points to species-specific differences in dewormer sensitivity and environmental persistence. Identifying resistance patterns at the species level will enable mechanistic understandings of cyathostomin anthelmintic resistance and targeted approaches to control them.
Publication Date: 2021-05-09 PubMed ID: 34065099PubMed Central: PMC8150961DOI: 10.3390/ani11051345Google 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.
- 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.
The paper presents a study that investigated reinfection rates of various species of a parasite, cyathostomin, in horses post anthelmintic treatment. Three types of commercial dewormers were administered and the number and types of cyathostomin species present were monitored over time. The study also noted species-specific differences in sensitivity and resistance to treatment.
Research Methodology
- The study involved nine horses that were treated with one of the three commercial dewormers namely Ivermectin (IVM) (n = 6), Moxidectin (MOX) (n = 8), or Pyrantel (PYR) (n = 8). The efficacy and effect of these treatments were compared with 90 untreated controls.
- The experiment was conducted during the months of June-September in the years 2017-2019.
- Fecal samples from the horses were collected every 14 days for a Study period of 98 days. These samples were examined to identify the species of cyathostomins present and observe the changes in their numbers over the course of the experiment.
- Fecal egg count reductions (FECR) were calculated to measure the effectiveness of the dewormers. A modified McMaster technique was used for this purpose.
- A total of nineteen cyathostomin species were identified by using 5.8S-ITS-2 profiling with amplicon sequencing, a molecular technique that allows precise and accurate identification of parasite species.
Results and Data Analysis
- The presence/absence of cyathostomin species were analyzed using the QIIME1 and R statistical software. This helped to document the change in the numbers of parasite species over time and the effectiveness of each type of dewormer.
- The results showed that Moxidectin (MOX) was associated with the lowest numbers of parasite species present over the study period, followed by Pyrantel (PYR) and then Ivermectin (IVM). However, fastest reduction in fecal egg counts (FECR) was noted for Pyrantel (PYR).
- Interestingly, it was found that the presence of seven cyathostomin species were not significantly affected by the treatment, indicating a certain degree of resistance in these specific species.
Conclusions and Implications
- The results of the study suggest species-specific differences in dewormer sensitivity, that is, different species of cyathostomins respond differently to each dewormer.
- The research also identified the species that were unaffected by the treatment, which should trigger further research to investigate the reasons for this resistance.
- Understanding resistance patterns at the species level can provide valuable insights for developing more effective anthelmintic treatments and adopting targeted approaches to control these parasitic infections in horses.
Cite This Article
APA
Johnson ACB, Biddle AS.
(2021).
The Use of Molecular Profiling to Track Equine Reinfection Rates of Cyathostomin Species Following Anthelmintic Administration.
Animals (Basel), 11(5), 1345.
https://doi.org/10.3390/ani11051345 Publication
Researcher Affiliations
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716, USA.
- Department of Animal and Food Sciences, University of Delaware, Newark, DE 19716, USA.
Grant Funding
- D18EQ-802 / Morris Animal Foundation
Conflict of Interest Statement
The authors declare no conflict of interest.
References
This article includes 81 references
- 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 Jul;174(1):23-32.
- Morariu S, Mederle N, Badea C, Dărăbuş G, Ferrari N, Genchi C. The prevalence, abundance and distribution of cyathostomins (small stongyles) in horses from Western Romania.. Vet Parasitol 2016 Jun 15;223:205-9.
- Mfitilodze MW, Hutchinson GW. Prevalence and abundance of equine strongyles (Nematoda: Strongyloidea) in tropical Australia.. J Parasitol 1990 Aug;76(4):487-94.
- Bucknell DG, Gasser RB, Beveridge I. The prevalence and epidemiology of gastrointestinal parasites of horses in Victoria, Australia.. Int J Parasitol 1995 Jun;25(6):711-24.
- Chapman MR, French DD, Klei TR. Gastrointestinal helminths of ponies in Louisiana: a comparison of species currently prevalent with those present 20 years ago.. J Parasitol 2002 Dec;88(6):1130-4.
- Love S, Murphy D, Mellor D. Pathogenicity of cyathostome infection.. Vet Parasitol 1999 Aug 31;85(2-3):113-21; discussion 121-2, 215-25.
- Garcia A, Brady H.A, Nichols W.T, Prien S. Equine Cyathostomin Resistance to Fenbendazole in Texas Horse Facilities. J. Equine Vet. Sci. 2013;33:223–228.
- Peregrine AS, McEwen B, Bienzle D, Koch TG, Weese JS. Larval cyathostominosis in horses in Ontario: an emerging disease?. Can Vet J 2006 Jan;47(1):80-2.
- Uhlinger C. Equine Small Strongyles: Epidemiology, Pathology, and Control. Compend. Contin. Educ. Pract. Vet. 1991 :863.
- Murphy D, Love S. The pathogenic effects of experimental cyathostome infections in ponies.. Vet Parasitol 1997 Jun;70(1-3):99-110.
- Mair TS, Cripps PJ, Ricketts SW. Diagnostic and prognostic value of serum protein electrophoresis in horses with chronic diarrhoea.. Equine Vet J 1993 Jul;25(4):324-6.
- Gokbulut C, McKellar QA. Anthelmintic drugs used in equine species.. Vet Parasitol 2018 Sep 15;261:27-52.
- Kaplan RM. Anthelmintic resistance in nematodes of horses.. Vet Res 2002 Sep-Oct;33(5):491-507.
- von Samson-Himmelstjerna G, Fritzen B, Demeler J, Schürmann S, Rohn K, Schnieder T, Epe C. Cases of reduced cyathostomin egg-reappearance period and failure of Parascaris equorum egg count reduction following ivermectin treatment as well as survey on pyrantel efficacy on German horse farms.. Vet Parasitol 2007 Mar 15;144(1-2):74-80.
- Kaplan RM, Klei TR, Lyons ET, Lester G, Courtney CH, French DD, Tolliver SC, Vidyashankar AN, Zhao Y. Prevalence of anthelmintic resistant cyathostomes on horse farms.. J Am Vet Med Assoc 2004 Sep 15;225(6):903-10.
- Nielsen MK, Banahan M, Kaplan RM. Importation of macrocyclic lactone resistant cyathostomins on a US thoroughbred farm.. Int J Parasitol Drugs Drug Resist 2020 Dec;14:99-104.
- Traversa D, von Samson-Himmelstjerna G, Demeler J, Milillo P, Schürmann S, Barnes H, Otranto D, Perrucci S, di Regalbono AF, Beraldo P, Boeckh A, Cobb R. Anthelmintic resistance in cyathostomin populations from horse yards in Italy, United Kingdom and Germany.. Parasit Vectors 2009 Sep 25;2 Suppl 2(Suppl 2):S2.
- Peregrine AS, Molento MB, Kaplan RM, Nielsen MK. Anthelmintic resistance in important parasites of horses: does it really matter?. Vet Parasitol 2014 Mar 17;201(1-2):1-8.
- Canever RJ, Braga PR, Boeckh A, Grycajuck M, Bier D, Molento MB. Lack of Cyathostomin sp. reduction after anthelmintic treatment in horses in Brazil.. Vet Parasitol 2013 May 1;194(1):35-9.
- Jacobs DE, Hutchinson MJ, Parker L, Gibbons LM. Equine cyathostome infection: suppression of faecal egg output with moxidectin.. Vet Rec 1995 Nov 18;137(21):545.
- DiPietro JA, Hutchens DE, Lock TF, Walker K, Paul AJ, Shipley C, Rulli D. Clinical trial of moxidectin oral gel in horses.. Vet Parasitol 1997 Oct;72(2):167-77.
- Demeulenaere D, Vercruysse J, Dorny P, Claerebout E. Comparative studies of ivermectin and moxidectin in the control of naturally acquired cyathostome infections in horses.. Vet Rec 1997 Oct 11;141(15):383-6.
- Borgsteede FH, Boersma JH, Gaasenbeek CP, van der Burg WP. The reappearance of eggs in faeces of horses after treatment with ivermectin.. Vet Q 1993 Mar;15(1):24-6.
- Boersema JH, Eysker M, Maas J, van der Aar WM. Comparison of the reappearance of strongyle eggs on foals, yearlings and adult horses after treatment with ivermectin or pyrantel.. Vet Q 1996 Mar;18(1):7-9.
- Boersema JH, Borgsteede FH, Eysker M, Saedt I. The reappearance of strongyle eggs in faeces of horses treated with pyrantel embonate.. Vet Q 1995 Mar;17(1):18-20.
- Nielsen M.K, Mittel L, Grice A, Erksine M, Graves E, Vaala W, Tully R.C, French D.D, Bowman R, Kaplan R.M. AAEP Parasite Control Guidelines 2019. .
- Scare JA, Lyons ET, Wielgus KM, Nielsen MK. Combination deworming for the control of double-resistant cyathostomin parasites - short and long term consequences.. Vet Parasitol 2018 Feb 15;251:112-118.
- Gilleard JS, Beech RN. Population genetics of anthelmintic resistance in parasitic nematodes.. Parasitology 2007;134(Pt 8):1133-47.
- Redman E, Whitelaw F, Tait A, Burgess C, Bartley Y, Skuce PJ, Jackson F, Gilleard JS. The emergence of resistance to the benzimidazole anthlemintics in parasitic nematodes of livestock is characterised by multiple independent hard and soft selective sweeps.. PLoS Negl Trop Dis 2015 Feb;9(2):e0003494.
- Leathwick DM, Sauermann CW, Nielsen MK. Managing anthelmintic resistance in cyathostomin parasites: Investigating the benefits of refugia-based strategies.. Int J Parasitol Drugs Drug Resist 2019 Aug;10:118-124.
- Corning S. Equine cyathostomins: a review of biology, clinical significance and therapy.. Parasit Vectors 2009 Sep 25;2 Suppl 2(Suppl 2):S1.
- Bellaw JL, Krebs K, Reinemeyer CR, Norris JK, Scare JA, Pagano S, Nielsen MK. Anthelmintic therapy of equine cyathostomin nematodes - larvicidal efficacy, egg reappearance period, and drug resistance.. Int J Parasitol 2018 Feb;48(2):97-105.
- Hodgkinson JE, Freeman KL, Lichtenfels JR, Palfreman S, Love S, Matthews JB. Identification of strongyle eggs from anthelmintic-treated horses using a PCR-ELISA based on intergenic DNA sequences.. Parasitol Res 2005 Mar;95(4):287-92.
- Traversa D, Iorio R, Otranto D, Giangaspero A, Milillo P, Klei TR. Species-specific identification of equine cyathostomes resistant to fenbendazole and susceptible to oxibendazole and moxidectin by macroarray probing.. Exp Parasitol 2009 Jan;121(1):92-5.
- Ionita M, Howe DK, Lyons ET, Tolliver SC, Kaplan RM, Mitrea IL, Yeargan M. Use of a reverse line blot assay to survey small strongyle (Strongylida: Cyathostominae) populations in horses before and after treatment with ivermectin.. Vet Parasitol 2010 Mar 25;168(3-4):332-7.
- Cernanská D, Paoletti B, Králová-Hromadová I, Iorio R, Cudeková P, Milillo P, Traversa D. Application of a Reverse Line Blot hybridisation assay for the species-specific identification of cyathostomins (Nematoda, Strongylida) from benzimidazole-treated horses in the Slovak Republic.. Vet Parasitol 2009 Mar 9;160(1-2):171-4.
- Kooyman FN, van Doorn DC, Geurden T, Wagenaar JA. Semi-quantitative differentiation of cyathostomin larval cultures by reverse line blot.. Vet Parasitol 2016 Jan 30;216:59-65.
- Bredtmann CM, Krücken J, Murugaiyan J, Kuzmina T, von Samson-Himmelstjerna G. Nematode Species Identification-Current Status, Challenges and Future Perspectives for Cyathostomins.. Front Cell Infect Microbiol 2017;7:283.
- van Doorn DC, Ploeger HW, Eysker M, Geurden T, Wagenaar JA, Kooyman FN. Cylicocyclus species predominate during shortened egg reappearance period in horses after treatment with ivermectin and moxidectin.. Vet Parasitol 2014 Dec 15;206(3-4):246-52.
- Hodgkinson JE, Lichtenfels JR, Mair TS, Cripps P, Freeman KL, Ramsey YH, Love S, Matthews JB. A PCR-ELISA for the identification of cyathostomin fourth-stage larvae from clinical cases of larval cyathostominosis.. Int J Parasitol 2003 Oct;33(12):1427-35.
- Hodgkinson JE, Love S, Lichtenfels JR, Palfreman S, Ramsey YH, Matthews JB. Evaluation of the specificity of five oligoprobes for identification of cyathostomin species from horses.. Int J Parasitol 2001 Feb;31(2):197-204.
- Chilton NB, Hoste H, Hung GC, Beveridge I, Gasser RB. The 5.8S rDNA sequences of 18 species of bursate nematodes (order Strongylida): comparison with rhabditid and tylenchid nematodes.. Int J Parasitol 1997 Jan;27(1):119-24.
- Leathers D., Office of The Delaware State Climatologist Off. [(accessed on 10 February 2021)];Del. State Climatol. Available online: http://climate.udel.edu/search-results/
- Larsen ML, Ritz C, Petersen SL, Nielsen MK. Determination of ivermectin efficacy against cyathostomins and Parascaris equorum on horse farms using selective therapy.. Vet J 2011 Apr;188(1):44-7.
- Collins A, Ke X. Primer1: Primer Design Web Service for Tetra-Primer ARMS-PCR. Open Bioinforma. J. 2012;6:55–58.
- Abou Elela S, Nazar RN. Role of the 5.8S rRNA in ribosome translocation.. Nucleic Acids Res 1997 May 1;25(9):1788-94.
- Dimitrova A.D, Gecheff K.I, Ananiev E.D. Methylation pattern of ribosomal rna genes in nor-deleted and nor- reconstructed barley lines (hordeum vulgare L.). organization of igs in rdna repeat unit. Genet. Plant. Phys. 2012;2:3–14.
- Magoč T, Salzberg SL. FLASH: fast length adjustment of short reads to improve genome assemblies.. Bioinformatics 2011 Nov 1;27(21):2957-63.
- Caporaso JG, Kuczynski J, Stombaugh J, Bittinger K, Bushman FD, Costello EK, Fierer N, Peña AG, Goodrich JK, Gordon JI, Huttley GA, Kelley ST, Knights D, Koenig JE, Ley RE, Lozupone CA, McDonald D, Muegge BD, Pirrung M, Reeder J, Sevinsky JR, Turnbaugh PJ, Walters WA, Widmann J, Yatsunenko T, Zaneveld J, Knight R. QIIME allows analysis of high-throughput community sequencing data.. Nat Methods 2010 May;7(5):335-6.
- Lichtenfels JR, Kharchenko VA, Dvojnos GM. Illustrated identification keys to strongylid parasites (Strongylidae: Nematoda) of horses, zebras and asses (Equidae).. Vet Parasitol 2008 Sep 15;156(1-2):4-161.
- Kumar S, Stecher G, Tamura K. MEGA7: Molecular Evolutionary Genetics Analysis Version 7.0 for Bigger Datasets.. Mol Biol Evol 2016 Jul;33(7):1870-4.
- Pecson BM, Barrios JA, Johnson DR, Nelson KL. A real-time PCR method for quantifying viable ascaris eggs using the first internally transcribed spacer region of ribosomal DNA.. Appl Environ Microbiol 2006 Dec;72(12):7864-72.
- R Core Team. R: A Language and Environment for Statistical Computing. R Foundatioon for Statistical Computing; Vienna, Austria: 2018.
- Lyons ET, Tolliver SC, Drudge JH. Historical perspective of cyathostomes: prevalence, treatment and control programs.. Vet Parasitol 1999 Aug 31;85(2-3):97-111; discussion 111-2, 215-25.
- Ogbourne CP. Observations on the free-living stages of strongylid nematodes of the horse.. Parasitology 1972 Jun;64(3):461-77.
- Silva AV, Costa HM, Santos HA, Carvalho RO. Cyathostominae (Nematoda) parasites of Equus caballus in some Brazilian states.. Vet Parasitol 1999 Sep 15;86(1):15-21.
- Kuzmina TA, Kharchenko VA, Starovir AI, Dvojnos GM. Analysis of the strongylid nematodes (Nematoda: Strongylidae) community after deworming of brood horses in Ukraine.. Vet Parasitol 2005 Aug 10;131(3-4):283-90.
- Reinemeyer CR, Smith SA, Gabel AA, Herd RP. The prevalence and intensity of internal parasites of horses in the U.S.A.. Vet Parasitol 1984 Jul;15(1):75-83.
- Zanet S, Battisti E, Labate F, Oberto F, Ferroglio E. Reduced Efficacy of Fenbendazole and Pyrantel Pamoate Treatments against Intestinal Nematodes of Stud and Performance Horses.. Vet Sci 2021 Mar 5;8(3).
- Sauermann CW, Leathwick DM, Lieffering M, Nielsen MK. Climate change is likely to increase the development rate of anthelmintic resistance in equine cyathostomins in New Zealand.. Int J Parasitol Drugs Drug Resist 2020 Dec;14:73-79.
- Rupasinghe D, Ogbourne C.P. Laboratory Studies on the Effect of Temperature on the Development of the Free-Living Stages of Some Strongylid Nematodes of the Horse. Z. Für Parasitenkd. 1978;55:249–253.
- Mfitilodze MW, Hutchinson GW. Development and survival of free-living stages of equine strongyles under laboratory conditions.. Vet Parasitol 1987 Jan;23(1-2):121-33.
- Rossanigo CE, Gruner L. Moisture and temperature requirements in faeces for the development of free-living stages of gastrointestinal nematodes of sheep, cattle and deer.. J Helminthol 1995 Dec;69(4):357-62.
- Von Ober-Blöbaum W. Untersuchungen Über Die Einwirkungen Physikalischer Einflü Sse Auf Die Larven von Pferdestrongyliden. Tierartzl Rundsch. 1932;47:812–815.
- Lucker J.T. Survival and development at low tempera tures of eggs and preinfective larvae horse strongyles. J. Agric. Res. 1941;63:193.
- Kaplan R.M, West E.M, Norat-Collazo L.M, Vargas J. A Combination Treatment Strategy Using Pyrantel Pamoate and Oxibendazole Demonstrates Additive Effects for Controlling Equine Cyathostomins. Equine Vet. Educ. 2014;26:485–491.
- Lyons ET, Kuzmina TA, Tolliver SC, Collins SS. Observations on development of natural infection and species composition of small strongyles in young equids in Kentucky.. Parasitol Res 2011 Dec;109(6):1529-35.
- Barnes EH, Dobson RJ. Population dynamics of Trichostrongylus colubriformis in sheep: computer model to simulate grazing systems and the evolution of anthelmintic resistance.. Int J Parasitol 1990 Nov;20(7):823-31.
- Dargatz DA, Traub-Dargatz JL, Sangster NC. Antimicrobic and anthelmintic resistance.. Vet Clin North Am Equine Pract 2000 Dec;16(3):515-36, ix-x.
- Sangster NC. Pharmacology of anthelmintic resistance in cyathostomes: will it occur with the avermectin/milbemycins?. Vet Parasitol 1999 Aug 31;85(2-3):189-201; discussion 201-4, 215-25.
- Dowdall SM, Matthews JB, Mair T, Murphy D, Love S, Proudman CJ. Antigen-specific IgG(T) responses in natural and experimental cyathostominae infection in horses.. Vet Parasitol 2002 Jun 26;106(3):225-42.
- Stratford CH, McGorum BC, Pickles KJ, Matthews JB. An update on cyathostomins: anthelmintic resistance and diagnostic tools.. Equine Vet J Suppl 2011 Aug;(39):133-9.
- Lyons ET, Tolliver SC, Drudge JH, Collins SS, Swerczek TW. Continuance of studies on Population S benzimidazole-resistant small strongyles in a Shetland pony herd in Kentucky: effect of pyrantel pamoate (1992-1999).. Vet Parasitol 2001 Jan 20;94(4):247-56.
- Gokbulut C, Nolan AM, McKellar QA. Plasma pharmacokinetics and faecal excretion of ivermectin, doramectin and moxidectin following oral administration in horses.. Equine Vet J 2001 Sep;33(5):494-8.
- Dobson RJ, LeJambre L, Gill JH. Management of anthelmintic resistance: inheritance of resistance and selection with persistent drugs.. Int J Parasitol 1996 Aug-Sep;26(8-9):993-1000.
- Terrill TH, Kaplan RM, Larsen M, Samples OM, Miller JE, Gelaye S. Anthelmintic resistance on goat farms in Georgia: efficacy of anthelmintics against gastrointestinal nematodes in two selected goat herds.. Vet Parasitol 2001 Jun 28;97(4):261-8.
- Durette-Desset MC, Beveridge I, Spratt DM. The origins and evolutionary expansion of the Strongylida (Nematoda).. Int J Parasitol 1994 Dec;24(8):1139-65.
- Cwiklinski K, Merga JY, Lake SL, Hartley C, Matthews JB, Paterson S, Hodgkinson JE. Transcriptome analysis of a parasitic clade V nematode: comparative analysis of potential molecular anthelmintic targets in Cylicostephanus goldi.. Int J Parasitol 2013 Oct;43(11):917-27.
- Tandon R, LePage KT, Kaplan RM. Cloning and characterization of genes encoding alpha and beta subunits of glutamate-gated chloride channel protein in Cylicocyclus nassatus.. Mol Biochem Parasitol 2006 Nov;150(1):46-55.
- Dorris M, De Ley P, Blaxter ML. Molecular analysis of nematode diversity and the evolution of parasitism.. Parasitol Today 1999 May;15(5):188-93.
- Blouin MS, Yowell CA, Courtney CH, Dame JB. Host movement and the genetic structure of populations of parasitic nematodes.. Genetics 1995 Nov;141(3):1007-14.
Citations
This article has been cited 3 times.- Elghandour MMMY, Maggiolino A, Vázquez-Mendoza P, Alvarado-Ramírez ER, Cedillo-Monroy J, De Palo P, Salem AZM. Moringa oleifera as a Natural Alternative for the Control of Gastrointestinal Parasites in Equines: A Review.. Plants (Basel) 2023 May 8;12(9).
- 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.
- Macdonald SL, Abbas G, Ghafar A, Gauci CG, Bauquier J, El-Hage C, Tennent-Brown B, Wilkes EJA, Beasley A, Jacobson C, Cudmore L, Carrigan P, Hurley J, Beveridge I, Hughes KJ, Nielsen MK, Jabbar A. Egg reappearance periods of anthelmintics against equine cyathostomins: The state of play revisited.. Int J Parasitol Drugs Drug Resist 2023 Apr;21:28-39.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists