Analyze Diet

Topic:Silage

Silage is a type of preserved forage commonly used in livestock feeding, created through the fermentation of high-moisture crops such as grass, corn, or legumes. In equine nutrition, the use of silage is less common than in other livestock species due to specific considerations regarding its fermentation process and potential health impacts on horses. Factors such as the acidity of silage, the presence of undesirable microorganisms, and its nutritional composition are important when evaluating its suitability for equine diets. This page compiles peer-reviewed research studies and scholarly articles that explore the nutritional value, safety, and implications of feeding silage to horses, examining aspects such as digestibility, palatability, and potential health risks.
Impact of different dietary regimens on the lipidomic profile of mare’s milk.
Food research international (Ottawa, Ont.)    April 29, 2022   Volume 156 111305 doi: 10.1016/j.foodres.2022.111305
Deng L, Yang Y, Li Z, Li J, Zhu Y, Meng Q, Liu J, Wang X.Despite mare's milk being highly nutritious and beneficial to human health, the effects of different dietary regimens on the lipid profile of mare's milk remain to be completely understood. Herein we employed targeted multiple reaction monitoring-based lipidomics with ultra-high performance liquid chromatography-quadrupole time-of-flight-mass spectrometry to compare the milk lipid profiles of mares fed: pasture grass (P), corn stover and concentrate (H), or cornsilage and concentrate (S). Overall, 461 lipids belonging to 17 subclasses were identified; 261 significantly different lipids were id...
The Effect of Ryegrass Silage Feeding on Equine Fecal Microbiota and Blood Metabolite Profile.
Frontiers in microbiology    August 23, 2021   Volume 12 715709 doi: 10.3389/fmicb.2021.715709
Zhu Y, Wang X, Liu B, Yi Z, Zhao Y, Deng L, Holyoak R, Li J.Silage is fed to horses in China and other areas in the world, however, knowledge about the impact of feeding silage on horse health is still limited. In the current study, 12 horses were assigned into two groups and fed ryegrass silage and ryegrass hay, respectively, for 8 weeks. High-throughput sequencing was applied to analyze fecal microbiota, while liquid chromatography-tandem mass spectrometry (LC-MS/MS) based metabolomics technique was used for blood metabolite profile to investigate the influence of feeding ryegrass silage (group S) compared to feeding ryegrass hay (group H) on equine ...
Effects of Pasture Grass, Silage, and Hay Diet on Equine Fecal Microbiota.
Animals : an open access journal from MDPI    May 7, 2021   Volume 11, Issue 5 doi: 10.3390/ani11051330
Zhu Y, Wang X, Deng L, Chen S, Zhu C, Li J.Diet is an important factor affecting intestinal microbiota in horses. Fecal microbiota is commonly used as a substitute for studying hindgut microbiota when investigating the relationship between intestinal microbial changes and host health. So far, no study has compared the difference between the fecal microbiota found in horses that are fed pasture grass, silage, and hay. The present study aims to characterize the fecal microbiota in horses that were exclusively on one of the three forage diets, and to analyze the potential impact of these forages, especially silage, on horse intestinal hea...
Safety of hexamethylene tetramine for pigs, poultry, bovines, sheep, goats, rabbits and horses.
EFSA journal. European Food Safety Authority    February 14, 2020   Volume 18, Issue 2 e06012 doi: 10.2903/j.efsa.2020.6012
Bampidis V, Azimonti G, Bastos ML, Christensen H, Dusemund B, Kouba M, Kos Durjava M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A....Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on hexamethylene tetramine (HMTA) for pigs, poultry, bovines, sheep, goats, rabbits and horses. In 2015, the FEEDAP Panel delivered an opinion on the safety and efficacy of HMTA. In that opinion, the Panel noted that the residues of HMTA in the silage amounted to about 5% of the inclusion level of 600 mg HMTA/kg fresh ensiling material. Since the HMTA residues in silage were analysed as formaldehyde, it was not possible to...
Fungal and chemical diversity in hay and wrapped haylage for equine feed.
Mycotoxin research    November 27, 2019   Volume 36, Issue 2 159-172 doi: 10.1007/s12550-019-00377-5
Andersen B, Phippen C, Frisvad JC, Emery S, Eustace RA.The presence of fungi and mycotoxins in silage (fermented maize) for cattle and other ruminants have been studied extensively compared to wrapped haylage (fermented grass) for horses and other monogastric animals. The purpose of this work was to examine the fungal diversity of wrapped haylage and conventional hay and to analyse the forage sample for fungal metabolites. Faeces samples were also analysed to study the fate of fungi and metabolites. Fungal diversity of the samples was determined by direct plating on DG18, V8 and MEA and chemical analyses were done using LC-MS/MS. The results show ...
Influence of Dietary Supplementation of Ensiled Devil Fish and Staphylococcus saprophyticus on Equine Fecal Greenhouse Gases Production.
Journal of equine veterinary science    June 11, 2019   Volume 79 105-112 doi: 10.1016/j.jevs.2019.05.023
García EDA, Khusro A, Pacheco EBF, Adegbeye MJ, Barbabosa-Pliego A, Lagunas BC, Salas JMC, Mateos RG, Aarti C, Elghandour MMMY.The present context was designed to investigate the efficacy of devil fish (DF; Plecostomus sp.) silage and Staphylococcus saprophyticus on fermentation characteristics as well as greenhouse gases production mitigation attributes in horses. Four levels of ensiled DF at 0 (control DF0), 6 (DF6), 12 (DF12), and 18 (DF18) % were added into the diet. Moreover, three doses of S. saprophyticus (0, 1, and 3 mL/g dry matter [DM]) were used for in vitro fecal fermentation. The use of ensiled DF resulted in increased (P < .0001) pH during fermentation. The asymptotic gas production was the highest (P...
Feeding Behavior of Mangalarga Marchador Weanlings Fed Sorghum Silage Versus Grass Hay.
Journal of equine veterinary science    February 13, 2019   Volume 75 90-92 doi: 10.1016/j.jevs.2019.02.001
Prado Silva RH, Carneiro de Rezende AS, Felipe da Silva Inácio D, Norberto F, Saraiva de Melo Queiroz JN, Melo MM, Colares de Araújo Moreira D....Mangalarga Marchador foals in Minas Gerais, Brazil, are usually weaned during the dry season, when there is a scarcity of forage. Although sorghum silage has been used to feed weanlings, the effect on their feeding behavior in comparison with grass hay has not been reported. Twelve Mangalarga Marchador weanlings were randomly assigned to two groups of six animals: SS: sorghum silage; VH: Vaquero hay. Both groups received commercial concentrate in the proportion of 1.2 kg.100 kg of the live weight and forage ad libitum. The animals were filmed for 48 hours, being timed: forage intake time, wate...
Atypical myopathy-associated hypoglycin A toxin remains in sycamore seedlings despite mowing, herbicidal spraying or storage in hay and silage.
Equine veterinary journal    January 30, 2019   Volume 51, Issue 5 701-704 doi: 10.1111/evj.13070
González-Medina S, Montesso F, Chang YM, Hyde C, Piercy RJ.Several pasture management strategies have been proposed to avoid hypoglycin A (HGA) intoxication in horses, but their efficacy has never been investigated. Objective: To evaluate the effect of mowing and herbicidal spraying on HGA content of sycamore seedlings and the presence of HGA in seeds and seedlings processed within haylage and silage. Methods: Experimental study. Methods: Groups of seedlings were mowed (n = 6), sprayed with a dimethylamine-based (n = 2) or a picolinic acid-based herbicide (n = 1). Seedlings were collected before intervention, and at 48 h, 1 and 2 weeks after. ...
Review: Feeding conserved forage to horses: recent advances and recommendations.
Animal : an international journal of animal bioscience    November 24, 2016   Volume 11, Issue 6 958-967 doi: 10.1017/S1751731116002469
Harris PA, Ellis AD, Fradinho MJ, Jansson A, Julliand V, Luthersson N, Santos AS, Vervuert I.The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the p...
Alkaloid-Containing Plants Poisonous to Cattle and Horses in Europe.
Toxins    December 8, 2015   Volume 7, Issue 12 5301-5307 doi: 10.3390/toxins7124884
Cortinovis C, Caloni F.Alkaloids, nitrogen-containing secondary plant metabolites, are of major interest to veterinary toxicology because of their occurrence in plant species commonly involved in animal poisoning. Based on epidemiological data, the poisoning of cattle and horses by alkaloid-containing plants is a relatively common occurrence in Europe. Poisoning may occur when the plants contaminate hay or silage or when forage alternatives are unavailable. Cattle and horses are particularly at risk of poisoning by Colchicum autumnale (meadow saffron), Conium maculatum (poison hemlock), Datura stramonium (jimson wee...
Effects of deoxynivalenol in naturally contaminated wheat on feed intake and health status of horses.
Mycotoxin research    September 30, 2015   Volume 31, Issue 4 209-216 doi: 10.1007/s12550-015-0234-6
Schulz AK, Kersten S, Dänicke S, Coenen M, Vervuert I.The present study examined the short-term effects of deoxynivalenol (DON), administered at two different concentrations via a feed preparation using naturally contaminated wheat, on feed intake, liver and kidney metabolism and immunomodulatory properties in horses. Twelve geldings were randomly assigned to one of three dietary treatments for 21 days. DON was provided via naturally contaminated wheat (14.6 ± 6.5 mg DON/kg dry matter). The daily feed intake was adjusted to 4 kg of wheat and 1.7 kg of silage per 100 kg of body weight (BW). Horses were fed one of the following diets: control whea...
Anaerobic digestion of horse dung mixed with different bedding materials in an upflow solid-state (UASS) reactor at mesophilic conditions.
Bioresource technology    February 17, 2014   Volume 158 111-118 doi: 10.1016/j.biortech.2014.02.034
Böske J, Wirth B, Garlipp F, Mumme J, Van den Weghe H.Aim of this study was to investigate the use of upflow anaerobic solid-state (UASS) digestion for treating horse manure. Biochemical methane potential (BMP) tests conducted for varying mixtures of dung (hay and silage feed) and bedding material (wheat straw, flax, hemp, wood chips) showed that straw mixed with hay horse dung has the highest potential of [Formula: see text] . Continuous mesophilic digestion was conducted for 238 days using a single-stage UASS reactor (27 L) and a two-stage UASS system with an anaerobic filter (AF, 21 L). Increasing the organic loading rate (OLR) from 2.5 to 4.5...
Epidemiology of intoxication of domestic animals by plants in Europe.
Veterinary journal (London, England : 1997)    April 6, 2013   Volume 197, Issue 2 163-168 doi: 10.1016/j.tvjl.2013.03.007
Cortinovis C, Caloni F.This review focuses on some of the most important poisonous plants in Europe and provides an overview of the poisoning episodes that have occurred in European countries. Poisoning of livestock and companion animals by plants is a relatively common occurrence. In Europe livestock and horses are commonly poisoned by Datura stramonium (Jimson weed), Senecio spp. (ragworts and groundsels), Quercus spp. (oak), Taxus baccata (European yew), Nerium oleander (oleander), Pteridium aquilinum (bracken fern), Robinia pseudoacacia (black locust) and Rhododendron spp. (rhododendrons and azaleas). Poisoning ...
Fresh and preserved green fodder modify effects of urinary acidifiers on urine pH of horses.
Journal of animal physiology and animal nutrition    March 30, 2013   Volume 98, Issue 2 239-245 doi: 10.1111/jpn.12071
Goren G, Fritz J, Dillitzer N, Hipp B, Kienzle E.Hay stabilises urine pH in horses. It is unknown whether this is an effect of structure or of chemical composition. In this study, four ponies (230-384 kg body weight [BW]) were fed six different diets with either a structure or a composition similar to hay with and without acidifiers in a cross-over experimental design in amounts to maintain body weight with the following main compounds: Fresh grass (GRASS), alfalfa hay (ALF), grass cobs (COBS), grass silage (SIL), straw (STR) or extruded straw (STRe) for 2 to 10 days. Urine pH was measured in all trials, blood pH, blood base excess and bicar...
Post mortem survey of peripheral dental caries in 510 Swedish horses.
Equine veterinary journal    June 9, 2010   Volume 42, Issue 4 310-315 doi: 10.1111/j.2042-3306.2009.00024.x
Gere I, Dixon PM.Peripheral caries (PC) of equine teeth is a poorly described disorder that can cause serious clinical problems if it progresses. Objective: To assess the prevalence, sites and severity of PC in a population of Swedish horses. Methods: A post mortem study of 510 equine skulls was performed in 2 Swedish equine abattoirs. Results: PC only affected the cheek teeth (CT) and was present in 6.1% (31/510) of skulls. It affected mainly the peripheral cementum, and 87% of PC in the 29 affected mature horses occurred in the 3 caudal CT (Triadan 09-11). Concurrent infundibular caries involving most maxill...
Type A botulism in horses in the United States: a review of the past ten years (1998-2008). Johnson AL, McAdams SC, Whitlock RH.The objective of the current retrospective study was to describe naturally occurring type A botulism in horses in the United States. In the past 10 years, the Botulism Laboratory at the University of Pennsylvania's School of Veterinary Medicine has identified 3 isolated cases and 8 outbreaks of type A botulism in horses via samples positive for Clostridium botulinum type A toxin or spores using the mouse bioassay test. Additional information was obtained by review of submission forms and by telephone or email interviews. Almost all type A cases and outbreaks occurred in the western United Stat...
[Two horses with neurological symptoms: could this be equine botulism?].
Tijdschrift voor diergeneeskunde    November 7, 2009   Volume 134, Issue 19 790-795 
Roest HI, de Bruijn CM, Picavet MT, Prins B, Parmentier D, de Zwart GM, Dijkstra YE, van Zijderveld FG.Symptoms, diagnosis and therapy of equine botulism are discussed by the presentation of two detailed reports of horses with neurological symptoms and the results of laboratory investigations over the period 2003-2008 in the Netherlands. In addition a brief summary of the available literature is presented. Prevailing symptoms of botulism in horses include paralysis of the tongue, salvation, dysphagia and paresis and paralysis of the skeletal muscles, as well as signs of colic. Symptoms and prognosis vary with the amount of botulinum neurotoxin (BoNT) involved. For early clinical diagnosis of bo...
Effects on the equine colon ecosystem of grass silage and haylage diets after an abrupt change from hay.
Journal of animal science    March 27, 2009   Volume 87, Issue 7 2291-2298 doi: 10.2527/jas.2008-1461
Muhonen S, Julliand V, Lindberg JE, Bertilsson J, Jansson A.The objective of this study was to investigate the effect of an abrupt change from grass hay (81% DM) to grass silage (36% DM) or grass haylage (55% DM), fed at similar DM intakes, and to compare the effects of silage and haylage on the composition and activities of the colon microflora. The forages were from the same swath harvested on the same day. Four adult colon-fistulated geldings were randomly assigned to diets in a crossover design. The study started with a preperiod when all 4 horses received the hay diet, followed by an abrupt feed change to the haylage diet for 2 horses and the sila...
Effects of crude protein intake from grass silage-only diets on the equine colon ecosystem after an abrupt feed change.
Journal of animal science    August 1, 2008   Volume 86, Issue 12 3465-3472 doi: 10.2527/jas.2007-0374
Muhonen S, Connysson M, Lindberg JE, Julliand V, Bertilsson J, Jansson A.The objective of this study was to investigate the effect of CP intake from 2 grass silage-only diets, differing in CP concentration, fed at similar DMI on the equine colon ecosystem after an abrupt feed change between the diets. Four adult right ventral colon-fistulated geldings were fed one silage-only diet high in CP (HP, 873 g of CP/d) and one diet providing recommended intakes (RP, 615 g of CP/d). An adaptation period of 15 d on either the HP or the RP diet was followed by 2 experimental periods when the diets were fed for 22 d each in a crossover design. Colon samples were taken before a...
Polyneuropathy associated with forage sources in Norwegian horses.
Journal of veterinary internal medicine    February 22, 2008   Volume 22, Issue 1 178-184 doi: 10.1111/j.1939-1676.2008.0023.x
Hanche-Olsen S, Teige J, Skaar I, Ihler CF.Cases of hindlimb digital extensor weakness of unknown etiology have been observed in Norway since 1995. Objective: We hypothesized that the observed bilateral extensor weakness was attributable to neuropathy of the distal nerves and that this was related to environmental factors, possibly dietary. Methods: Seventy-five horses with digital extensor weakness occurring from 1995 to 2004 are described. Methods: Eleven horses were examined at The Norwegian School of Veterinary Science, and the medical records of 64 horses seen in ambulatory practice were reviewed. Results: There was no apparent se...
Judgement of hygienic quality of roughage in horse stables in Switzerland.
Journal of animal physiology and animal nutrition    January 31, 2008   Volume 92, Issue 4 432-437 doi: 10.1111/j.1439-0396.2007.00755.x
Wichert B, Nater S, Wittenbrink MM, Wolf P, Meyer K, Wanner M.In 46 horse farms all over Switzerland, the hygienic quality of the roughage (including silages) was investigated. Therefore, a macroscopic examination as well as the microbial counts (bacteria, yeasts and moulds) was carried out. Further, the contents of lipopolysaccharides (LPS) and the contamination with deoxynivalenol (DON) were determined. In all roughages, the dry matter (DM) content was measured and in silages additionally the pH was measured. Predominantly, the straw showed a lower hygienic quality than hay and silages. The LPS contents were significantly higher in straw than those in ...
[Nutrient content and adequacy of roughage for horse nutrition: an investigation under Swiss conditions].
Schweizer Archiv fur Tierheilkunde    April 7, 2007   Volume 149, Issue 3 103-109 doi: 10.1024/0036-7281.149.3.103
Nater S, Wanner M, Wichert B.For horses no special tables related to nutrients for Swiss roughage exist. For this reason samples of hay, straw, silage/haylage and green forage were taken from 46 horse keeping farms in 22 cantons. The samples were judged by sense and following the nutrient--and macromineral--content as well as the content of fructans were analysed. Regarding its quality no sample was totally inadequate for horses. The mean contents of crude protein in Swiss hay for horses were clearly lower than in hay for ruminants and in German hay for horses. The mineral contents (calcium, magnesium, phosphorus) showed ...
Is snow a sufficient source of water for horses kept outdoors in winter? A case report.
Acta veterinaria Scandinavica    August 20, 2005   Volume 46, Issue 1-2 19-22 doi: 10.1186/1751-0147-46-19
Mejdell CM, Simensen E, Bøe KE.Due to extreme weather conditions, a flock of outwintered Icelandic horses had to manage for several days on snow as the source of free water. They were fed grass silage ad lib, and any change in feed consumption was not observed. After nine days, blood samples were taken and analysed for plasma osmolality, they were subjected to a simple clinical examination, and offered drinking water. Osmolality levels were within normal limits and mean value did not differ significantly from samples which previously were taken of the same individuals. The general condition of the horses was normal, with no...
Mathematical modelling of digesta passage rate, mean retention time and in vivo apparent digestibility of two different lengths of hay and big-bale grass silage in ponies.
The British journal of nutrition    July 8, 2003   Volume 90, Issue 1 109-118 doi: 10.1079/bjn2003869
Moore-Colyer MJ, Morrow HJ, Longland AC.Welsh-cross pony geldings (about 300 kg live weight) were used in a 4x4 Latin square experiment to determine the rate of passage and apparent digestibility of unchopped big-bale grass silage (BBL), chopped big-bale grass silage (BBS), unchopped grass hay (HL) and chopped grass hay (HS) offered at approximately 15 g/kg live weight per d. On day 1 of collection weeks, ponies were fed 85 g ytterbium chloride hexahydrate-marked feed 1.5 h after the morning meal. Total faecal collections commenced 8 h later and continued for 168 h. Apparent digestibilities of feed DM, organic matter (OM), crude pro...
The use of cardboard bedding material as part of an environmental control regime for heaves-affected horses: in vitro assessment of airborne dust and aeroallergen concentration and in vivo effects on lung function.
Veterinary journal (London, England : 1997)    July 2, 2002   Volume 163, Issue 3 319-325 doi: 10.1053/tvjl.2001.0658
Kirschvink N, Di Silvestro F, Sbaï I, Vandenput S, Art T, Roberts C, Lekeux P.This study aimed to test whether shredded cardboard is an appropriate minimum-dust bedding material for heaves-affected horses. Results of standardized in vitro measurement of airborne dust and aeroallergen concentrations of cardboard bedding were significantly lower than those of common bedding materials. Six heaves-affected horses in clinical remission after pasturing were stabled for two months on cardboard bedding and fed grass silage. Pulmonary function tests (PFT: ventilatory mechanics, arterial blood gases, airway inflammation scoring, bronchoalveolar cytology) were performed before, du...
[Accident report: animal nutrition in veterinary medicine–actual cases: houndstongue (Cynoglossum officinale) in pasture–a health hazard for horses].
DTW. Deutsche tierarztliche Wochenschrift    December 28, 1999   Volume 106, Issue 11 475-477 
Zentek J, Aboling S, Kamphues J.Meteorism and colics were observed in horses after grazing on young pasture. The botanical analysis of a sample as taken by the owner revealed a great diversity of grasses, herbs and legumes. Houndstongue (Cynoglossum officinale) in its rosette stage was identified in amounts of 1% of the total sample, although this cannot be regarded as representative for the composition of the green fodder. This plant has been reported to be highly toxic for horses and other species, mainly during the early growth stadium due to its contents of pyrrolizidin alkaloids with a strong hepatotoxic activity. In th...
Effect of a set stabled environmental control on pulmonary function and airway reactivity of COPD affected horses.
Veterinary journal (London, England : 1997)    May 2, 1998   Volume 155, Issue 2 189-195 doi: 10.1016/s1090-0233(98)80018-x
Vandenput S, Votion D, Duvivier DH, Van Erck E, Anciaux N, Art T, Lekeux P.The aim of this study was to evaluate the respiratory function of horses affected with chronic obstructive pulmonary disease (COPD) when maintained in a barn on wood shavings and fed grass silage for a period of 6 weeks. The mechanics of breathing, blood gas analysis and bronchial reactivity were examined on five horses with COPD at the end of the environment-controlled period (Period B) and the results compared with values obtained after 2 months at pasture (Period A) and after the onset of clinical signs of acute crisis (Period C). The results showed that clinical and functional parameters w...
Environmental control to maintain stabled COPD horses in clinical remission: effects on pulmonary function.
Equine veterinary journal    April 16, 1998   Volume 30, Issue 2 93-96 doi: 10.1111/j.2042-3306.1998.tb04466.x
Vandenput S, Duvivier DH, Votion D, Art T, Lekeux P.The objective of this study was to test the hypothesis that stabled COPD horses can be maintained in clinical remission by replacing hay by grass silage and bedding made of wood shavings (Period B) and of wheat straw (Period C) during 6 weeks, respectively. At the end of these different periods, the pulmonary function of the horses was assessed by mechanics of breathing and arterial blood analyses. These results were compared to those measured in clinical remission obtained after 2 months in pasture (Period A). No significant difference was observed between these 3 periods neither to values ob...
Airborne dust and aeroallergen concentrations in different sources of feed and bedding for horses.
The veterinary quarterly    December 31, 1997   Volume 19, Issue 4 154-158 doi: 10.1080/01652176.1997.9694762
Vandenput S, Istasse L, Nicks B, Lekeux P.Standardized methods were used to make quantitative and qualitative assessments of respirable dust and aeroallergens in feed and bedding for horses. Concentrations of airborne dust were measured by using a Rion particle counter, and levels of major aeroallergens implicated in chronic obstructive pulmonary disease were measured by using an Andersen sampler. Laboratory conditions allowed comparison of the different sources of forage, supplements, and bedding without external influences such as ventilation, external temperature and horse activity affecting the result. Grass silages of approximate...
Morphology of starch digestion in the horse.
Zentralblatt fur Veterinarmedizin. Reihe A    June 1, 1997   Volume 44, Issue 4 207-221 doi: 10.1111/j.1439-0442.1997.tb01103.x
Kienzle E, Pohlenz J, Radicke S.Structure of starch in feed and chyme of horses (7 with a cannula at the caudal end of the jejunum and 2 with a cecal fistula) after feeding high starch diets (maize: whole, broken, ground, expanded and as silage, oats: whole, rolled or ground, rolled barley, raw potatoes, and tapioca) was investigated by light and electron microscopy. Structure of feed starch and morphology or starch degradation in the chyme corresponded to data on preileal starch digestibility which was investigated in a parallel study. Barriers for starch digestion in the gastrointestinal tract of the horse were structure o...