The Fibre Requirements of Horses and the Consequences and Causes of Failure to Meet Them.
Abstract: Failure to meet the minimum forage requirement of 1.5% of the horse's bodyweight and the opportunity for foraging for a minimum of 8 h a day (not going without this opportunity longer than four to five consecutive hours) can have both physiological and behavioural consequences. To provide an energy source for horses, rations often include starch rather than fibre. This can result in health issues related to the gastrointestinal tract (GIT) in the horse. In the stomach, the main concern is equine gastric ulcer syndrome (EGUS) and, more specifically, equine squamous gastric disease (ESGD). Ulcerations are caused either by increasing acidity in the stomach (from starch ingestion and reduced saliva production) or splashing of acidic juices caused by a lack of a forage barrier prior to exercise or prolonged periods without fibrous feed intake, which allows the stomach to collapse and spread acidic gastric fluids into the upper squamous regions of the stomach. In the hindgut, starch that has escaped digestion in the small intestine causes microbial instability and increased production of volatile fatty acids (VFA) and lactic acid. This puts horses at great risk for acidosis and subsequent laminitis. Shifts in the hindgut microbiota will also affect a horse's behaviour via the gut-brain axis, as well as potentially compromise immune function. Reduced fluid intake caused by reduced saliva production can result in colic. Choosing a fibrous alternative for starch in a high-energy diet greatly reduces the risk of EGUS and acidosis and improves digestion, GIT pH, body condition, behaviour, immune functions, and performance. Providing hay can reduce crib-biting, wood-chewing, coprophagia, the consumption of bedding, aggression, and stress, and subsequently increase social bonding and affiliation with conspecifics. Adequate fibre intake is related to reduced clinical signs of EGUS, reduced reactivity, and better adaptation to weaning. Lignophagia (wood chewing) has also been observed in horses that are foraging, and this is thought to reflect low fibre content in the available forage (for example, early vegetative, lush pasture).
Publication Date: 2023-04-20 PubMed ID: 37106977PubMed Central: PMC10135103DOI: 10.3390/ani13081414Google 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
- Review
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 study discusses the importance of a suitable amount of dietary fibre for horses, the consequences when this need is not met, and the common reasons why such failings occur. It examines these issues through the lens of both physiological and behavioural aspects.
Importance of Fibre in Horse Diets
- This paper highlights that horses should have at least 1.5% of their bodyweight in forage and 8 hours of foraging time each day.
- A key driver for meeting this requirement is to prevent health complications tied to the gastrointestinal tract (GIT), including equine gastric ulcer syndrome (EGUS) and equine squamous gastric disease (ESGD).
- When starch is over-represented in the horse’s diet, less saliva is produced, which can increase the acidity of the stomach and cause stomach ulcers.
- Undigested starch can trigger microbial instability and lead to excess volatile fatty acids and lactic acid in the hindgut, putting horses at risk for acidosis and laminitis.
Behaviours Linked to Dietary Fibre Deficiency
- Deficits in the hindgut microbiota can alter a horse’s behaviour and may weaken its immune system.
- Behavioural changes such as crib-biting, wood-chewing, coprophagia (feces-eating), aggression could indicate insufficient fibre intake.
- Conversely, higher levels of social behaviour and stress reduction occur with adequate fibre consumption.
- Stress adjustment during weaning is also linked with fibre consumption.
- Wood chewing (lignophagia) is speculated to be related to the low fibre content in available forage.
Fibre vs Starch in Diets
- The research emphasizes the efficacy of replacing starch in high-energy diets with fibrous alternatives.
- Benefits include lowered risks of EGUS and acidosis, enhanced digestion, proper GIT pH, better body condition, improved behaviour, stronger immune functions, and ideally, superior performance.
- A simple and practical way to boost fibre content is to supply hay to horses, especially important when other forage is not adequately fibrous.
Cite This Article
APA
Ermers C, McGilchrist N, Fenner K, Wilson B, McGreevy P.
(2023).
The Fibre Requirements of Horses and the Consequences and Causes of Failure to Meet Them.
Animals (Basel), 13(8).
https://doi.org/10.3390/ani13081414 Publication
Researcher Affiliations
- School of Environment and Rural Science, University of New England, Armidale, NSW 2351, Australia.
- Equilize Horse Nutrition Pty Ltd., Tamworth, NSW 2340, Australia.
- School of Agriculture and Food Science, The University of Queensland, Gatton, QLD 4343, Australia.
- School of Life and Environmental Science, The University of Sydney, Sydney, NSW 2006, Australia.
- School of Environment and Rural Science, University of New England, Armidale, NSW 2351, Australia.
Conflict of Interest Statement
The authors declare no conflict of interest.
References
This article includes 96 references
- Richards N, Hinch G, Rowe J. The effect of current grain feeding practices on hindgut starch fermentation and acidosis in the Australian racing Thoroughbred.. Aust. Vet. J. 2006;84:402–407.
- Hoffman C.J, Costa L.R, Freeman L.M. Survey of Feeding Practices, Supplement Use, and Knowledge of Equine Nutrition among a Subpopulation of Horse Owners in New England.. J. Equine Vet. Sci. 2009;29:719–726.
- Visser E, Van Wijk-Jansen E. Diversity in horse enthusiasts with respect to horse welfare: An explorative study.. J. Vet. Behav. Clin. Appl. Res. 2012;7:295–304.
- Cipriano-Salazar M, Adegbeye M.J, Elghandour M.M.M.Y, Barbabosa-Pilego A, Mellado M, Hassan A, Salem A.Z.M. The Dietary Components and Feeding Management as Options to Offset Digestive Disturbances in Horses.. J. Equine Vet. Sci. 2019;74:103–110.
- Ringmark S, Roepstorff L, Essen-Gustavsson B, Revold T, Lindholm A, Hedenstrom U, Rundgren M, Ogren G, Jansson A. Growth, training response and health in Standardbred yearlings fed a forage-only diet.. Animal 2013;7:746–753.
- Richardson K, Murray J.A.M.D. Fiber for Performance Horses: A Review.. J. Equine Vet. Sci. 2016;46:31–39.
- Vinassa M, Cavallini D, Galaverna D, Baragli P, Raspa F, Nery J, Valle E. Palatability assessment in horses in relation to lateralization and temperament.. Appl. Anim. Behav. Sci. 2020;232:105110.
- Harris P.A, Ellis A.D, Fradinho M.J, Jansson A, Julliand V, Luthersson N, Santos A.S, Vervuert I. Review: Feeding conserved forage to horses: Recent advances and recommendations.. Animal 2017;11:958–967.
- . The Importance of Fibre for Horses.. .
- Buxton D, Redfearn D. Plant Limitations to Fiber Digestion and Utilization.. J. Nutr. 1997;127:814S–818S.
- Allen V, Batello C, Berretta E, Hodgson J, Kothmann M, Li X, McIvor J, Milne J, Morris C, Peeters A. An international terminology for grazing lands and grazing animals.. Grass Forage Sci. 2011;66:2.
- Richards N, Nielsen B, Finno C. Nutritional and Non-nutritional Aspects of Forage.. Vet. Clin. N. Am. Equine Pract. 2021;37:43–61.
- Cavallini D, Penazzi L, Valle E, Raspa F, Bergero D, Formigoni A, Fusaro I. When Changing the Hay Makes a Difference: A Series of Case Reports.. J. Equine Vet. Sci. 2022;113:103940.
- Hothersall B, Nicol C. Effects of diet on behavior–normal and abnormal.. .
- Elia J.B, Erb H.N, Houpt K.A. Motivation for hay: Effects of a pelleted diet on behavior and physiology of horses.. Physiol. Behav. 2010;101:623–627.
- Merritt A.M, Julliand V. Gastrointestinal physiology.. .
- Al Jassim R.A.M, Scott P.T, Trebbin A.L, Trott D, Pollitt C.C. The genetic diversity of lactic acid producing bacteria in the equine gastrointestinal tract.. FEMS Microbiol. Lett. 2005;248:75–81.
- McMeniman N, Elliott R, Groenendyk S, Dowsett K. Synthesis and absorption of cysteine from the hindgut of the horse.. Equine Vet. J. 1987;19:192–194.
- Carroll F, Goss H, Howell C. The Synthesis of B Vitamins in the Horse.. J. Anim. Sci. 1949;8:290–299.
- Richards N. Enhancing Starch Digestion in the Equine Small Intestine.. .
- Muhonen S, Sadet-Bourgeteau S, Julliand V. Effects of Differences in Fibre Composition and Maturity of Forage-Based Diets on the Microbial Ecosystem and Its Activity in Equine Caecum and Colon Digesta and Faeces.. Animals 2021;11:2337.
- Raspa F, Vervuert I, Capucchio M, Colombino E, Bergero D, Forte C, Greppi M, Cavallarin L, Giribaldi M, Antoniazzi S. A high-starch vs. high-fibre diet: Effects on the gut environment of the different intestinal compartments of the horse digestive tract.. BMC Vet. Res. 2022;18:187.
- Salter R, Hudson R. Feeding Ecology of Feral Horses in Western Alberta.. J. Range Manag. 1979;32:221–225.
- Tyler S. The behaviour and social organisation of the New Forest Ponies.. Anim. Behav. Monogr. 1972;5:85–196.
- Duncan P. Time-budgets of Carmargue horses II. Time budgets of adult horses and weaned sub-adults.. Behaviour 1980;72:26–49.
- Ellis A. Biological basis of behaviour in relation to nutrition and feed intake in horses; Proceedings of the 5th European Workshop Equine Nutrition; Cirencester, UK. 19–22 September 2010;. .
- Arena I, Marliani G, Sabioni S, Gabai G, Bucci D, Accorsi P. Assessment of horses’ welfare: Behavioral, hormonal, and husbandry aspects.. J. Vet. Behav. 2021;41:82–90.
- Luthersson N, Nielsen K.H, Harris P, Parkin T.D.H. Risk factors associated with equine gastric ulceration syndrome (EGUS) in 201 horses in Denmark.. Equine Vet. J. 2009;41:625–630.
- Sykes B.W, Hewetson M, Hepburn R.J, Luthersson N, Tamzali Y. European College of Equine Internal Medicine Consensus Statement—Equine Gastric Ulcer Syndrome in Adult Horses.. J. Vet. Intern. Med. 2015;29:1288–1299.
- Sadet-Bourgeteau S, Philippeau C, Julliand V. Effect of concentrate feeding sequence on equine hindgut fermentation parameters.. Animal 2017;11:1146–1152.
- Hassel D, Aldridge B, Drake C, Snyder J. Evaluation of dietary and management risk factors for enterolithiasis among horses in California.. Res. Vet. Sci. 2008;85:476–480.
- Dosi M, Kirton R, Hallsworth S, Keen J, Morgan R. Inducing weight loss in native ponies: Is straw a viable alternative to hay?. Vet. Rec. 2020;187:e60.
- Jansson A, Lindenberg J. A forage-only diet alters the metabolic response of horses in training.. Animal 2012;6:1939–1946.
- Swami V, Hochstöger S, Kargl E, Stieger S. Hangry in the field: An experience sampling study on the impact of hunger on anger, irritability, and affect.. PLoS ONE 2022;17:e0269629.
- McGreevy P, Cripps P, French N, Green L, Nicol C. Management factors associated with stereotypic and redirected behaviour in the Thoroughbred horse.. Equine Vet. J. 1995;27:86–91.
- Manson G.J. Stereotypies: A critical review.. Anim. Behav. 1991;41:1015–1037.
- Nicol C. Understanding equine stereotypies.. Equine Vet. J. 1999;31:20–25.
- McGreevy. Equine Behavior: A Guide for Veterinarians and Equine Scientists.. .
- Mayes E, Duncan P. Temporal Patterns of Feeding Behaviour in Free-Ranging Horses.. Behaviour 1986;96:105–129.
- Van den Berg M, Lee C, Brown W. Browsing—An overlooked aspect of feeding management in horses?; Proceedings of the Australasian Equine Science Symposium; Gold Coast, Australia. 13–15 June 2012.. .
- Nicol C, Davidson H, Harris P, Waters A, Wilson A. Study of crib-biting and gastric inflammation and ulceration in young horses.. Vet. Rec. 2002;151:658–662.
- Clegg H.A, Buckley P, Friend M.A, McGreevy P.D. The ethological and physiological characteristics of cribbing and weaving horses.. Appl. Anim. Behav. Sci. 2008;109:68–76.
- Keenan D.M. Bark chewing by horses grazed on irrigated pasture.. Aust. Vet. J. 1986;63:234–235.
- McBride S.D, Parker M.O, Roberts K, Hemmings A. Applied neurophysiology of the horse; implications for training, husbandry and welfare.. Appl. Anim. Behav. Sci. 2017;190:90–101.
- Hanis F, Chung E.L.T, Kamalludin M.H, Idrus Z. Do nutrient composition of feedstuffs affect the proportion of oral stereotypies and redirected behaviors among horse working groups?. J. Vet. Behav. 2021;46:7–14.
- Hothersall B, Casey R. Undesired behaviour in horses: A review of their development, prevention, management and association with welfare.. Equine Vet. Educ. 2012;24:479–485.
- Willard J.G, Willard J.C, Wolfram S.A, Baker J.P. Effect of Diet on Cecal pH and Feeding Behavior of Horses.. J. Anim. Sci. 1977;45:87–93.
- Raspa F, Tarantola M, Muca E, Bergero D, Soglia D, Cavallini D, Vervuert I, Bordin C, De Palo P, Valle E. Does Feeding Management Make a Difference to Behavioural Activities and Welfare of Horses Reared for Meat Production?. Animals 2022;12:1740.
- Raspa F, Dinardo F.R, Vervuert I, Bergero D, Bottero M.T, Pattono D, Dalmasso A, Vinassa M, Valvassori E, Bruno E. A Fibre- vs. cereal grain-based diet: Which is better for horse welfare? Effects on intestinal permeability, muscle characteristics and oxidative status in horses reared for meat production.. J. Anim. Physiol. Anim. Nutr. 2022;106:313–326.
- Benhajali H, Richard-Yris M, Ezzaouia M, Charfi F, Hausberger M. Foraging opportunity: A crucial criterion for horse welfare?. Animal 2009;3:1308–1312.
- Hockenhull J, Creighton E. Management practices associated with owner-reported stable-related and handling behaviour problems in UK leisure horses.. Appl. Anim. Behav. Sci. 2014;155:49.
- Fureix C, Menguy H, Hausberger M. Partners with bad temper: Reject or cure? A study of chronic pain and aggression in horses.. PLoS ONE 2010;5:e12434.
- Murray M, Grodinsky C, Anderson C, Radue P, Schmidt G. Gastric ulcers in horses: A comparison of endoscopic findings in horses with and without clinical signs.. Equine Vet. J. 1989;21:68–72.
- Henderson A.J.Z. Don’t Fence Me In: Managing Psychological Well Being for Elite Performance Horses.. J. Appl. Anim. Welf. Sci. 2007;10:309–329.
- Buchanan B, Frank A. Treatment and prevention of equine gastric ulcer syndrome.. Vet. Clin. N. Am. Equine Pract. 2004;19:575–597.
- Mal M.E, McCall C.A. The influence of handling during different ages on a halter training test in foals.. Appl. Anim. Behav. Sci. 1996;50:115–120.
- Hoffman R.M, Kronfeld D.S, Holland J.L, Greiwe-Crandell K.M. Preweaning diet and stall weaning method influences on stress response in foals.. J. Anim. Sci. 1995;73:2922–2930.
- Delank K, Reese S, Erhard M, Wohr A.-C. Behavioral and hormonal assessment of stress in foals (Equus caballus) throughout the weaning process.. PLoS ONE 2023;18:e0280078.
- Goodwin D, Davidson H.P.B, Harris P. A note on behaviour of stabled horses with foraging devices in mangers and buckets.. Appl. Anim. Behav. Sci. 2007;105:238–243.
- McGreevy P, Berger J, Brauwere N.D, Doherty O, Harrison A, Fiedler J, Jones C, McDonnell S, McLean A, Nakonechny L. Using the five domains model to assess the adverse impacts of husbandry, veterinary, and equitation interventions on horse welfare.. Animals 2018;8:41.
- Mellor D.J, Beausoleil N.J, Littlewood K.E, McLean A.N, McGreevy P.D, Jones B, Wilkins C. The 2020 Five Domains Model: Including Human–Animal Interactions in Assessments of Animal Welfare.. Animals 2020;10:1870.
- Luthersson N, Nadeau J.A. Gastric ulceration.. .
- Jonsson H, Egenvall A. Prevalence of gastric ulceration in Swedish Standardbreds in race training.. Equine Vet. J. 2006;38:209–213.
- Nieto J.E, Snyder J.R, Beldomenico P, Aleman M, Kerr J.W, Spier S.J. Prevalence of gastric ulcers in endurance horses—A preliminary report.. Vet. J. 2004;167:33–37.
- le Jeune S.S, Nieto J.E, Dechant J.E, Snyder J.R. Prevalence of gastric ulcers in Thoroughbred broodmares in pasture: A preliminary report.. Vet. J. 2009;181:251–255.
- McClure S.R, Glickman L.T, Glickman N.W. Prevalence of gastric ulcers in show horses.. J. Am. Vet. Med. Assoc. 1999;215:1130–1133.
- Andrews F.M, Nadeau J.A. Clinical syndromes of gastric ulceration in foals and mature horses.. Equine Vet. J. Suppl. 1999;31:30–33.
- Lorenzo-Figueras M, Merritt A.M. Effects of exercise on gastric volume and pH in the proximal portion of the stomach of horses.. Am. J. Vet. Res. 2002;63:1481–1487.
- Hepburn R. Gastric ulceration in horses.. In Practice 2011;33:116–124.
- Nadeau J.A, Andrews F.M, Patton C.S, Argenzio R.A, Mathew A.G, Saxton A.M. Effects of hydrochloric, acetic, butyric, and propionic acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses.. Am. J. Vet. Res. 2003;64:404–412.
- Chapa M. Effect of Dietary Fiber Level on the Healing of Gastric Ulcers in Horses.. .
- Böhm S, Mitterer T, Iben C. The impact of feeding a high-fibre and high-fat concentrated diet on the recovery of horses suffering from gastric ulcers.. Pferdeheilkunde 2018;34:237–246.
- Hewetson M, Venner M, Volquardsen J, Sykes B.W, Hallowell G.D, Vervuert I, Fosgate G.T, Tulamo R.-M. Diagnostic accuracy of blood sucrose as a screening test for equine gastric ulcer syndrome (EGUS) in weanling foals.. Acta Vet. Scand. 2018;60:24.
- Shawaf T, El-Deeb W.M, Elgioushy M. The Contribution of Specific and Nonspecific Biomarkers in Diagnosis of Equine Gastric Ulcer Syndrome (EGUS) Under Field Condition.. J. Equine Vet. Sci. 2020;84:102853.
- Kauter A, Epping L, Semmier T, Antao E.-M, Kannapin D, Stoeckle S, Gehlen H, Lubke-Becker A, Gunther S, Wieler L. The gut microbiome of horses: Current research on equine enteral microbiota and future perspectives.. Anim. Microbiome 2019;1:14.
- Blikslager A.T. Colic Prevention to Avoid Colic Surgery: A Surgeon’s Perspective.. J. Equine Vet. Sci. 2019;76:1–5.
- Longland A.C, Byrd B.M. Pasture Nonstructural Carbohydrates and Equine Laminitis.. J. Nutr. 2006;136:2099S–2102S.
- Potter S, Bamford N, Harris P, Bailey S. Incidence of laminitis and survey of dietary and management practices in pleasure horses and ponies in south-eastern Australia.. Aust. Vet. J. 2017;95:370–374.
- Brøkner C, Bach Knudsen K.E, Karaman I, Eybye K.L, Tauson A.H. Chemical and physicochemical characterisation of various horse feed ingredients.. Anim. Feed Sci. Technol. 2012;177:86–97.
- Williamson A, Rogers C.W, Firth E.C. A survey of feeding, management and faecal pH of Thoroughbred racehorses in the North Island of New Zealand.. N. Z. Vet. J. 2007;55:337–341.
- Hemsworth L, Jongman E, Coleman G. Recreational horse welfare: The relationships between recreational horse owner attributes and recreational horse welfare.. Appl. Anim. Behav. Sci. 2015;165:1–16.
- Honoré E.K, Uhlinger C.A. Equine feeding practices in central north carolina: A preliminary survey.. J. Equine Vet. Sci. 1994;14:424–429.
- . What Should I Feed My Horse?. .
- Geor R.J. Nutritional management of the equine athlete.. .
- . Seven Rules to Make Feeding Your Horse Simple.. .
- . The Rules of Feeding Your Horse.. .
- Lawrence L. Nutrient needs of performance horses.. Rev. Bras. De Zootec. 2008;37:206–210.
- Kaya-Karasu G, Huntington P, Iben C, Murray J.-A. Feeding and Management Practices for Racehorses in Turkey.. J. Equine Vet. Sci. 2018;61:108–113.
- Council N.R. Nutrient Requirements of Horses: Sixth Revised Edition.. .
- Harris P.A, Coenen M, Geor R.J. 26—Controversial areas in equine nutrition and feeding management: The Editors’ views.. .
- Gordon M.E, McKeever K.H, Bokman S, Betros C.L, Manso-Filho H.C, Liburt N.R, Streltsova J.M. Training-induced energy balance mismatch in Standardbred mares.. Equine Comp. Exerc. Physiol. 2006;3:73–82.
- Jones R.D, McGreevy P.D, Robertson A, Clarke A.F, Wathes C. Survey of the designs of racehorse stables in the south-west of England.. Equine Vet. J. 1987;19:454–457.
- Ivester K.M, Couëtil L.L, Moore G.E. An observational study of environmental exposures, airway cytology, and performance in racing thoroughbreds.. J. Vet. Intern. Med. 2018;32:1754–1762.
- Olave C.J, Ivester K.M, Couetil L.L, Kritchevsky J.E, Tinkler S.H, Mukhopadhyay A. Dust exposure and pulmonary inflammation in Standardbred racehorses fed dry hay or haylage: A pilot study.. Vet. J. 2021;271:105654.
- McLean A, McGreevy P. Horse-training techniques that may defy the principles of learning theory and compromise welfare.. J. Vet. Behav. Clin. Appl. Res. 2010;5:187–195.
- McLean A, McGreevy P. Ethical equitation: Capping the price horses pay for human glory.. J. Vet. Behav. Clin. Appl. Res. 2010;5:203–209.
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