Forage is a primary component of the equine diet, consisting mainly of grasses, hay, and legumes that provide essential nutrients and fiber. It plays a significant role in maintaining digestive health and supporting the overall well-being of horses. The nutritional composition of forage can vary based on factors such as plant species, maturity at harvest, and environmental conditions. Proper management and selection of forage are important for meeting the dietary needs of horses and preventing issues such as colic or laminitis. This page compiles peer-reviewed research studies and scholarly articles that explore the nutritional value, management practices, and impact of forage on equine health and performance.
Huang X, Li Q, Li X, Li C, Li J, He L, Jing H, Yang F, Li X.China's equine industry has shifted from traditional rough grazing to modern intensive farming, expanding the roles of horses into eventing, leisure, tourism, and meat and dairy production. Concurrently, equine nutrition has evolved from a forage-based diet to a more diverse regimen incorporating grain supplements to meet the heightened energy demands of intensive farming. However, nutrient digestibility and glycemic response vary considerably based on grain type, starch content, composition, and structural properties. Optimal grain selection is therefore essential for energy supplementation a...
Karačonji IB, Jelača T, Jurič A, Vrdoljak AL.Opiates such as morphine and codeine are substances often misused to improve the performance of racing horses during competitions and are therefore on the International Federation for Equestrian Sports' list of prohibited substances. However, a positive antidoping test may be due to the consumption of feed (mainly lucerne or oats) contaminated by opium poppy containing the alkaloids morphine and codeine. In order to determine whether a positive antidoping test is the result of an intentional abuse of opiates or consumption of feed contaminated by poppies, we optimised conditions for the extrac...
Rodríguez-Valencia V, Olive MM, Le Goff G, Faisse M, Bourel M, L'Ambert G, Vollot B, Tolsá-García MJ, Paupy C, Roiz D.The spread of the West Nile (WNV) and Usutu (USUV) flaviviruses in Europe in recent decades highlights the urgent need to understand the transmission networks of these pathogens as a basis for effective decision-making. These viruses are part of a complex disease cycle that involves birds as principal hosts and humans and horses as dead-end hosts. Our study aims to uncover the intricate relationships between the main mosquito vector of these viruses, Culex pipiens L. (Diptera: Culicidae) and its feeding preferences based on the forage ratio among several host species, primarily birds in a lan...
Kaštovská E, Mastný J, Choma M, Čapek P, Jirků M, Bitomský M, Konvička M.Based on a growing understanding of the role of wild megafauna in the functioning of natural ecosystems, trophic rewilding by large herbivores is increasingly used as a nature-based solution to mitigate biodiversity loss and climate change in Europe and beyond. Despite the growing interest in implementing nature-based approaches to restore key non-productive ecosystem services, there is relatively little data available to assess the benefits and risks of rewilding projects. We therefore investigated the effects of year-round grazing by large ungulates on plant biomass characteristics and their...
Cameron L, Challinor M, Armstrong S, Kennedy A, Hollister S, Fletcher K.Horses evolved to live in herds, continuously moving and foraging. Domestic horses often have limited social contact and movement, with high calorific intake, contributing to obesity. "Track grazing" is an increasingly popular management system, but evidence of its impact on weight management, behaviour, and welfare is limited. Horses (n = 19) resident at HorseWorld (UK) were observed July to October 2023, monitoring bodyweight (kg), Body Conditions Score (BCS), hoof health, behaviour, and welfare indicators. Horses on track grazing systems lost significantly more bodyweight (kg) (F(1,15) = 8....
González-Medina S, Hyde C, Chang YM, Piercy RJ.Sycamore tree-derived hypoglycin A (HGA) toxin causes atypical myopathy (AM), an acute, equine pasture-associated rhabdomyolysis but incidence fluctuates. Objective: Investigate whether tree or environmental factors influence HGA concentration in sycamore material and are associated with AM relative risk. Methods: Retrospective and experimental prospective study. Methods: UK sycamore population, seed production and AM incidence data were obtained. HGA concentration was measured in seeds from trees from 10 different central UK locations. The effect of tar spot infection, seed maturity, tree tru...
Webster AP, Price T, Ingersoll T, Suagee-Bedore JK, White RR.Our objectives were to use a quantitative literature review to explore dietary and feed factors influencing apparent total-tract digestibility of dry matter (DMD), crude protein (CPD), neutral detergent fiber (NDFD), ether extract (EED), non-structural carbohydrates (NSCD), non-fiber carbohydrates (NFCD), and residual organic matter (rOMD) in equine diets, and to assess their contributions to digestible energy (DE) supplies. Data from 54 studies were modeled using linear mixed-effect regressions, with publication as a random effect to account for study variability. For each nutrient, five mode...
DeBoer M, Rieck T, Johnson L, Redenius H, Martinson K.Horses have become more intensively managed, including the use of hay nets to increase intake time and reduce hay waste, but their impact on health is not well known. The objectives were to compare changes in subluxations, range of motion, and the pain-pressure threshold in the axial skeleton of horses fed hay with (NET) or without (CON) hay nets. In September 2021, 13 adult horses were blocked by bodyweight (BW) and randomly assigned to the NET or CON treatments for one year. After one year, horses switched treatments and the trial concluded in September 2023. Horses were housed in dry lots w...
Jensen RB, Walslag IH, Marcussen C, Thorringer NW, Junghans P, Nyquist NF.Feeding order of forage and concentrate might affect gastric emptying and subsequently digestion in horses. The objective of this study was to measure gastric emptying in combination with metabolic and digestive responses in the plasma and caecum, respectively, when changing the feeding order of oats (O) and hay (H) (oats first then hay: O-H vs. hay first then oats: H-O). Four caecum cannulated horses were used in a 2×2 crossover design, with two 12-day periods consisting of 10 d of diet adaptation and two days of data collection. Hay was fed at 0600, 1400 and 2000 h, while oats were fed in ...
Phelipon R, Hennes N, Ruet A, Bret-Morel A, Górecka-Bruzda A, Lansade L.Societal concerns for animal welfare extend to all domestic species, including high-level sport horses. The welfare of these horses, notably highlighted during the recent Olympics, has garnered significant public interest, prompting inquiries into their living conditions. Animal welfare studies have emphasised three key needs crucial to equine welfare: unlimited access to forage, freedom of movement, and social interactions with peers, commonly referred to as the "3Fs"-access to Forage, Freedom of movement, and interactions with Friend conspecifics. However, the feasibility and benefits of sat...
Böswald LF, Gottschalk C, Kaltner F, Merk J, Schwaiger K, Kienzle E.While previous reports come mostly from the southern Americas, several outbreaks of hypersalivation in horses were observed in Middle Europe from 2016 to 2018. Objective: To describe feed-induced hypersalivation in European horses. Methods: Analysis of feedstuffs. Methods: Veterinarians and horse or stable owners were encouraged to submit feedstuffs from case outbreaks of hypersalivation in which, infectious diseases or other systemic causes of the syndrome were ruled out and intoxication was suspected. Feedstuff analysis was performed, including gross examination, microscopic analysis of fine...
Springer RW, Cherry NM, Muir JP, Raub RH, Wellmann KB, Jones TN.Recent changes in legislation have put hempseed meal (Cannabis sativa L.; HSM) under consideration as a potential livestock feedstuff. Digestibility of HSM has been researched in other species, however, there are little data in horses. The study objective was to determine the in vitro true digestibility (IVTD) of HSM compared to common equine feedstuffs. An in vitro split-split plot design used four geldings (8.5 ± 3.9yr; 558.4 ± 31.0kg; 6.0 ± 0.4 BCS) to investigate the IVTD of HSM compared to alfalfa hay (ALF), Coastal Bermudagrass hay (CBH), soybean meal (SBM), rice bran pellets (RBP), a...
Farmer Long J, Duberstein J, Costin K, Callaway T, Abrams A, Wassel B, Toal K, Duberstein K.Pasture tracks are a modern equine housing trend often implemented as a weight control strategy due to the belief that they promote movement, though this is not proven experimentally. To test movement of horses housed in pasture tracks as compared to conventional pasture housing, two experiments were performed using a track (0.2ha, 3.5m in width, 561 m total distance) created around the perimeter of a 2.0 ha pasture. In experiment 1, eight horses were paired and rotated between three treatment locations: track (T), small 2 ha pasture housed within the track (SP), and a larger 20 ha pasture on ...
Silva RC, Coelho GJ, Sousa MBF, Caldas CS, Maciel RP, Mezzomo R, Gomes DÍ, Neta ERDS, Tavares FB, Alves KS, Oliveira LRS.In this study, we analyzed the effects of including açaí kernel, in the experimental diets fed to horses on the intake and digestibility of their nutrient and the resultant effects on the behavior of horses. The experiments were conducted in Federal Rural University of Amazonia. Five mares with no defined breeds, were allocated to five treatments (the replacement of Mombaça grass (Megathyrsus maximus) with crushed açaí kernel at 0, 18.75, 37.50, 56.25, and 75% levels of dry matter), in a 5 × 5 Latin square design. The animals were housed in covered stalls with concrete floors, equipp...
Ivester KM, Ni JQ, Couetil LL, Peters TM, Tatum M, Willems L, Park JH.Affordable particulate matter (PM) monitors suitable for use on horses will facilitate the evaluation of PM mitigation methods and improve the management of equine asthma. Objective: Calibrate a real-time wearable PM monitor (Black Beauty [BB]) and compare the PM exposures of horses fed dry or soaked hay. Methods: Laboratory calibration; complete cross-over feed trial. Methods: Side-by-side sampling with BB monitors and tapered element oscillating microbalances (TEOMs) was performed under varying concentrations of PM from alfalfa hay. Linear regression was used to derive a calibration formula ...
Bishop RC, Kemper AM, Clark LV, Wilkins PA, McCoy AM.Equine gastrointestinal microbial communities vary across the gastrointestinal tract and in response to diet or disease. Understanding the composition and stability of gastric fluid microbiota in healthy horses is a prerequisite to understanding changes associated with the development of disease. The objective of this study was to describe microbial communities in the gastric fluid and feces of healthy horses longitudinally. Horses were maintained on pasture (6 weeks), stabled (5 weeks), then returned to pasture. A consistent forage diet was provided throughout. Native gastric fluid and feces ...
Kerley BS, Harris P, Lea K, McClendon M, Adams AA.Forage low in nonstructural carbohydrates (NSC) is recommended for insulin dysregulated (ID) horses, indicating the importance of an accurate forage analysis. However, it remains to be fully understood how handling forage samples pre-analysis impacts nutrient values. The objective of this study was to compare the effect of fresh-forage storage-handling methods: microwave-oven (MO; 9kw; 70s then stored at -20℃), room temperature (20℃), 3℃, -20℃, and -80℃. Subsamples collected from a mixed-grass pasture and a ryegrass plot were analyzed for crude protein (CP), water soluble carbohydrat...
Daniels SP, Whiteside EJ, Martin S, Moore-Colyer MJS, Harris P.Feedstuffs, especially ensiled forage, may be detrimental to equid oral health by exposing the oral cavity to low pH. This study aimed to identify if salivary pH was altered by 1) a range of different feedstuffs and (2) specifically by feeding haylages with differing nutrient profiles. Two studies were conducted. The first measured oral pH following five feedstuffs, (hay, haylage, unmolassed sugarbeet pulp, unmolassed alfalfa chaff and rolled oats), tested individually over five days. Saliva (≥1 ml) was collected in triplicate, prior to feeding, directly after ingesting 500 g of each feedstu...
Froidurot A, Jacotot E, Julliand S, Grimm P, Julliand V.Despite their low quantity and abundance, the cellulolytic bacteria that inhabit the equine large intestine are vital to their host, as they enable the crucial use of forage-based diets. Fibrobacter succinogenes is one of the most important intestinal cellulolytic bacteria. In this study, Fibrobacter sp. HC4, one cellulolytic strain newly isolated from the horse cecum, was characterized for its ability to utilize plant cell wall fibers. Fibrobacter sp. HC4 consumed only cellulose, cellobiose, and glucose and produced succinate and acetate in equal amounts. Among genes coding for CAZymes, 26% o...
Bachmann M, Schusser GF, Wensch-Dorendorf M, Pisch C, Bochnia M, Santo MM, Netzker H, Woitow G, Thielebein J, Kesting S, Riehl G, Greef JM....Concentrations of starch, mono- and disaccharides, fructans, hemicellulose and cellulose were analysed in feed and gastric digesta of horses in relation to acid insoluble ash as a marker indigestible in the stomach. Twenty-four horses were allocated to pasture 24 h/d (PST; n = 4), hay ad libitum (HAY; n = 8), hay ad lib. and oats at 1 g starch/kg body weight (BWT)/meal (OS1; n = 6) and hay ad lib. and oats at 2 g starch/kg BWT/meal (OS2; n = 5). One horse was excluded from the analysis. The horses were fed the ration a minimum of 34 days. Following euthanasia and dissection, digesta was sample...
Lovász L, Korner-Nievergelt F, Amrhein V.A challenge in grassland conservation is to maintain both the openness and the heterogeneity of the habitat to support the diversity of their animal communities, including birds-a taxon that is known to be sensitive to disturbance. An increasingly used management tool in European grassland conservation, especially in rewilding projects, is grazing by large herbivores such as horses and cattle. These grazers are believed to create and maintain patchy landscapes that promote diversity and richness of other species, but their influence on birds is often debated by conservationists, who raise conc...
Leishman EM, Sahar M, Cieslar S, Darani P, Ellis JL.To properly formulate diets, the ability to accurately estimate feed intake is critical as the amount of feed consumed will influence the amount of nutrients delivered to the animal. Inaccurate intake estimates may lead to under- or over-feeding of nutrients to the animal. Individual differences in equine forage intake are well-known, but predictive equations based on animal and nutritional factors are not comprehensive. The objective of the present study was to consolidate the current body of knowledge in the published literature on voluntary forage DM intake (VFDMI) in equines and conduct a ...
Kenny LB, Smarsh DN.Existing data on the equine hay market and buying preferences in Pennsylvania (PA) is outdated and more recent data is needed. The objective of this project was to characterize the practices and attitudes of PA horse hay buyers. An online survey was created and distributed. It received 435 total responses (of these, 346 were complete responses) from PA horse hay buyers from October 2021 to February 2022. Data presented (descriptive statistics) represents the percentage of respondents answering that question. Most (76%) respondents were in the recreational sector of the horse industry and the m...
Janeiro-Otero A, Álvarez X, Dormann CF.Galician forests in northwestern Spain are subject to frequent wildfires with high environmental and economic costs. In addition, due to the consequences of climate change, these fires are becoming more virulent, occurring throughout the year, and taking place in populated areas, in some cases involving the loss of human life. Therefore, forest fire prevention is even more relevant than mitigating its consequences. Given the costs involved in forestry work, alternative measures to reduce fuel load and create vegetation gaps are needed. One involves grazing by an endemic species of feral horses...
Machado M, Queiroz-Machado CRR, Queiroz F, Gardner DR, Riet-Correa F.A Mimosa pudica var. unijuga-associated toxicity affecting horses occurred in Araguari, Triângulo Mineiro, Southeast Brazil. Affected horses had gradual hair loss of the mane and tail and endocrine dermatosis after grazing for three months during the dry season on a paddock invaded by the plant. The main histological lesions include compact ortho-keratotic hyperkeratosis and numerous flame follicles. Toxicological analysis by HPLC-UV demonstrated 0.8 mg/g of mimosine in the leaves.
Hart R, Bailey A, Farmer J, Duberstein K.Mastication is the initial phase of digestion and is crucial to equine health due to its role in saliva production and food particle reduction. Hay nets have been promoted to slow the rate of hay consumption, with many styles of slow feeders available. Limited research has shown that nets may slow consumption, but no research has examined their effect on the horse's chewing frequency and patterns. The objective of this study was to compare chew frequency (CF, total number of chews/kg consumed) and chew duration (CD, total minutes chewed/kg consumed), as well as distribution of chews over a fee...
Gartland B, Strunk W, Schulte B, DeGraves F, Koostra J.Horses can become obese and develop related health issues such as laminitis from excessive grazing on high-quality pasture grass; limiting pasture intake can allow weight loss to occur. The objective of this study was to determine the effect of space-restricted rotational grazing on body weight (BW) and time budgets in horses. Eight mature geldings and mares with maintenance-only requirements were randomly assigned to either a space-restricted rotational grazing group (SRG; BW 512 ± 6 kg; n = 4) or a continuous grazing group (CG; BW 517 ± 49 kg; n = 4) for 42 d SRG horses grazed an area with...
Silva AH, Lucena JEC, Taran FMP, Cunha DS, Almeida JAT, Lima RS, Dias WS, Santiago JM.This study aimed to compare the digestibility of tropical grasses by horses by the in vivo method using mobile nylon bags with the in vitro digestibility method using horse feces as a source of inoculum. Five horses were used in a 2 × 5 factorial design with randomized blocks featuring two methods (in vivo and in vitro) and five grasses: Tifton 85 hay (Cynodon spp.), sixweeks threeawn grass (Aristida adsencionis, Linn), Alexandergrass (Brachiaria plantaginea (Link) Hitchc.), capim-de-raiz (Chloris orthonoton, Doell), and Sabi grass (Urochloa mosambicensis). No difference (P>0.05) was foun...
Bordin C, Raspa F, Greppi M, Harris P, Ellis AD, Roggero A, Palestrini C, Cavallini D, Bergero D, Valle E.In the last decade, haynets and slow feeders have been promoted as sustainable tools to improve the feeding management of horses and reduce forage waste, but little is known about their effects on ponies. Therefore, the aim of this study was to analyze the effects of different hay feeding methods on the ingestive behaviors, intake rate and mouth shaping of ponies belonging to two breed types, which are characterized by different head morphologies. Shetland type (SH, n = 5) and Welsh/Cob type (WC, n = 4) ponies were fed hay using four feeding methods: on the ground (G), a fully filled h...
Köninger M, von Velsen-Zerweck A, Eiberger C, Löffler C, Töpper A, Visscher C, Reckels B, Vervuert I.The aim of this study was to examine the nutrient composition and feed hygiene of alfalfa as well as investigate the feed intake, blood, urine and faecal parameters of horses fed alfalfa haylage (AS) compared with alfalfa hay (AH) and meadow hay (MH). A total of 11 geldings were fed ad libitum (2.1% dry matter (DM) of body weight (BW)) with alfalfa haylage, alfalfa hay and meadow hay (MH) in a Latin square design. On days 0 and 21 of the feeding period, blood samples were analysed for kidney and liver parameters. Faecal samples were analysed for pH, DM and short-chain fatty acids (SCFAs). Spon...
Bonin SJ, Clayton HM, Lanovaz JL, Johnston T.Previous studies have suggested that temporomandibular joint (TMJ) kinematics depend on the type of food being masticated, but accurate measurements of TMJ motion in horses chewing different feeds have not been published. Objective: The temporomandibular joint has a larger range of motion when horses chew hay compared to pellets. Methods: An optical motion capture system was used to track skin markers on the skull and mandible of 7 horses as they chewed hay and pellets. A virtual marker was created on the midline between the mandibles at the level of the 4th premolar teeth to represent the ove...
Bamford NJ, Potter SJ, Baskerville CL, Harris PA, Bailey SR.The importance of including exercise with dietary modification for the management of obese equids is not clearly understood. Objective: To evaluate the effect of a practical low-intensity exercise regimen, in addition to dietary restriction, on indices of insulin sensitivity (SI) and plasma adipokine concentrations in obese equids. Methods: Twenty-four obese (body condition score [BCS] ≥ 7/9) horses and ponies. Methods: Over a 12-week period, animals received either dietary restriction only (DIET) or dietary restriction plus low-intensity exercise (DIET+EX). All animals were provided wit...
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...
Moore-Colyer MJ, Lumbis K, Longland A, Harris P.Five different hays were used to determine the effect of 5 different soaking and steaming treatments on the water soluble carbohydrate and microbial (bacteria and mould) contents of UK hay. Hays were subjected to the following 5 treatments: 1. Dry; 2. Steamed for 50 minutes in the Haygain- 600 steamer; 3. Soaked in water at 16°C for 9 hours; 4. Steamed then soaked and 5. Soaked then steamed. Post treatment hays were tested for water soluble carbohydrates, bacteria and mould contents. Differences between means were determined using ANOVA and least significant difference with hay (5), bale (3) ...
Nedjadi T, Moran AW, Al-Rammahi MA, Shirazi-Beechey SP.The diet of the horse, pasture forage (grass), is fermented by the equine colonic microbiota to short-chain fatty acids, notably acetate, propionate and butyrate. Short-chain fatty acids provide a major source of energy for the horse and contribute to many vital physiological processes. We aimed to determine both the mechanism of butyrate uptake across the luminal membrane of equine colon and the nature of the protein involved. To this end, we isolated equine colonic luminal membrane vesicles. The abundance and activity of cysteine-sensitive alkaline phosphatase and villin, intestinal luminal ...
Cavallini D, Penazzi L, Valle E, Raspa F, Bergero D, Formigoni A, Fusaro I.Dry hay (composed of grass, legumes, or a mixture of the two) provides the primary source of alimentary fiber in stabled horses with limited access to fresh pasture. However, hay can also give rise to health problems in the horse, depending on the quality and quantity of its components. Pathologies may be rooted in biological problems, such as inadequate digestion disturbances, or reflect mechanical difficulties-for example, due to the presence of sharp plant parts that irritate the oral mucosa, or due to physical intake problems that inhibit consumption. Unwanted plants in the hay may cause s...
Lane HE, Burns TA, Hegedus OC, Watts MR, Weber PS, Woltman KA, Geor RJ, McCutcheon LJ, Eades SC, Mathes LE, Belknap JK.Insulin dysregulation, obesity, and exposure to high-nonstructural carbohydrate (NSC) forage are risk factors for equine metabolic syndrome-associated laminitis (EMSAL); high systemic insulin concentrations in EMSAL are proposed to induce cellular dysregulation in the digital lamellae through activation of the insulin-like growth factor-1 receptor. Objective: To use a dietary challenge model (DCM) and a euglycaemic-hyperinsulinaemic clamp (EHC) model to assess lamellar growth factor-related signalling. Methods: Lamellar phospho (P)-protein concentrations of signalling proteins important in gro...
Cheeke PR.Plant toxins are the chemical defenses of plants against herbivory. Grasses have relatively few intrinsic toxins, relying more on growth habit to survive defoliation and endophytic fungal toxins as chemical defenses. Forage grasses that contain intrinsic toxins include Phalaris spp. (tryptamine and carboline alkaloids), sorghums (cyanogenic glycosides), and tropical grasses containing oxalates and saponins. Toxic effects of these grasses include neurological damage (Phalaris staggers), hypoxia (sudangrass), saponin-induced photosensitization (Brachiaria and Panicum spp.), and bone demineraliza...
Cymbaluk NF, Christison GI.Horses are reared in all types of weather. Temperatures as diverse as -40 degrees C to 40 degrees C are tolerated by horses. The nutrient requirement most influenced by cold weather is energy. In cold weather, feeding good quality hays free-choice is usually sufficient for mature horses in good body condition. Grain may have to be fed when poor quality hays are used. Hot weather (greater than 30 degrees C) necessitates heat loss to maintain body core temperature. Horses sweat to reduce body heat. Heat stress can be minimized by feeding diets that reduce the heat increment. Use of grain and fat...
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...
Morrison PK, Newbold CJ, Jones E, Worgan HJ, Grove-White DH, Dugdale AH, Barfoot C, Harris PA, Argo CM.Obesity is an important equine welfare issue. Whilst dietary restriction is the most effective weight-loss tool, individual animals range in their weight-loss propensity. Gastrointestinal-derived bacteria play a fundamental role in host-health and have been associated with obesity and weight-loss in other species. This study evaluated the faecal microbiome (next-generation sequencing of 16S rRNA genes) of 15 obese Welsh Mountain pony mares, in the same 11-week period across 2 years (n = 8 Year 1; n = 7 Year 2). Following a 4-week acclimation period (pre-diet phase) during which t...
Sorensen RJ, Drouillard JS, Douthit TL, Ran Q, Marthaler DG, Kang Q, Vahl CI, Lattimer JM.The effect of hay type on the microbiome of the equine gastrointestinal tract is relatively unexplored. Our objective was to characterize the cecal and fecal microbiome of mature horses consuming alfalfa or Smooth Bromegrass (brome) hay. Six cecally cannulated horses were used in a split-plot design run as a crossover in two periods. The whole plot treatment was ad libitum access to brome or alfalfa hay fed over two 21-d acclimation periods with subplots of sampling location (cecum and rectum) and sampling hour. Each acclimation period was followed by a 24-h collection period where cecal and f...
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...
Weinert-Nelson JR, Biddle AS, Williams CA.Diet is a key driver of equine hindgut microbial community structure and composition. The aim of this study was to characterize shifts in the fecal microbiota of grazing horses during transitions between forage types within integrated warm- (WSG) and cool-season grass (CSG) rotational grazing systems (IRS). Eight mares were randomly assigned to two IRS containing mixed cool-season grass and one of two warm-season grasses: bermudagrass [Cynodon dactylon (L.) Pers.] or crabgrass [Digitaria sanguinalis (L.) Scop.]. Fecal samples were collected during transitions from CSG to WSG pasture sections (...
Moore BE, Dehority BA.The effects of diet and hindgut defaunation (removal of protozoa from the hindgut) on diet digestibility (Trial 1) and on total and cellulolytic bacterial and fungal concentrations in the cecum and colon (Trial 2) were investigated. A high-forage (HF) diet, 90% alfalfa hay-10% concentrate, or a higher-concentrate (HC) diet, 60% alfalfa hay-40% concentrate, was limit-fed. In Trial 1, defaunation resulted in a slight decrease in DM digestibility (P < .1) and had no effect on cellulose digestibility. Dry matter digestibility was higher (P < .001) with the HC diet; however, no differences were obs...
McGowan CM, Dugdale AH, Pinchbeck GL, Argo CM.Few studies have examined the effect of dietary restriction in horses with equine metabolic syndrome (EMS). This study aimed to determine improvements in insulin sensitivity following dietary restriction for 6 weeks, and to determine if the improvement would be greater in horses receiving short-chain fructo-oligosaccharides (sc-FOS). Dietary management involved feeding grass hay, restricted to 1.25% of body mass (BM) as daily dry matter intake and soaked in cold water prior to feeding, with the addition of a vitamin and mineral nutraceutical supplement with or without the addition of sc-FOS (1...
Pearson RA, Merritt JB.Four donkeys and four ponies maintained in climate rooms, were provided with meadow hay or barley straw supplemented with minerals and vitamins ad libitum. Both diets were given to all animals for periods of 21 days. Measurements were made during the last seven days following single doses of two non-absorbable markers (Cr-fibre and Co-EDTA). After six weeks the donkeys repeated the trial, walking 14 km and ascending 260 m five days per week. At rest ponies ate more than donkeys, however the donkeys showed a higher digestibility of dry matter (DM), organic matter (OM) and acid detergent fibre (...
Rapson JL, Schott HC, Nielsen BD, McCutcheon LJ, Harris PA, Geor RJ.Age and diet may affect insulin sensitivity (SI) but these factors have received limited investigation in horses. Objective: To measure minimal model parameters during an insulin-modified frequently sampled intravenous glucose tolerance test (FSIGTT) after adaptation to a forage only diet (HAY) or forage supplemented with either starch/sugar-rich (SS) or oil/fibre-rich (FF) concentrate feeds; and to assess glucose and insulin responses to a standardised meal challenge (SMC, 4 g/kg BW of SS) after diet adaptation in adult and aged mares. Methods: Latin square design with eight adult (5-12 yea...
Elia JB, Erb HN, Houpt KA.The natural diet of free-ranging horses is grass, which is typically high in fiber and calorically dilute, however diets for high performance domestic horses are often low in fiber and calorically dense. The aim of the study was to determine the motivation of horses for hay when fed a low roughage diet. Their motivation could be used to determine if low roughage diets compromise the welfare of horses. Eight mares were fed two different diets in counterbalanced order: ad libitum orchard grass hay; a complete pelleted feed (pellets). Each trial lasted three weeks, with a one-week transition peri...
Murray MJ, Schusser GF.A glass combined pH-reference electrode was placed in the stomachs of 5 adult horses and pH was recorded every 6 mins for 24 h while (1) feed and all bedding materials were withheld for 24 h (unfed), (2) horses had free access to Timothy grass hay for 24 h (fed), and (3) horses had free access to Timothy grass hay and were treated with ranitidine, 6.6 mg/kg body weight, orally, every 8 h for 48 h (fed + ranitidine). There was a significant (P = 0.007) difference in median 24-h gastric pH amongst the 3 protocols, the value being 3.1 in fed horses and 1.55 in unfed horses (P = 0.05) and 4.6 in f...
Olave CJ, Ivester KM, Couetil LL, Kritchevsky JE, Tinkler SH, Mukhopadhyay A.Respirable dust exposure is linked to airway inflammation in racehorses. Feeding haylage may reduce dust exposure by 60-70%. The objective of this study was to compare dust exposure, airway cytology, and inflammatory cytokine concentrations between horses fed haylage or hay over 6 weeks while in training. Seven healthy Standardbred horses were randomly assigned to be fed alfalfa hay (n = 3) or grass-alfalfa mix haylage (n = 4) for six weeks while training on a treadmill. Dust exposure was measured gravimetrically at the breathing zone. Endotoxin and β-glucan concentrations in respirable dust ...
Husted L, Sanchez LC, Olsen SN, Baptiste KE, Merritt AM.Stall housing has been suggested as a risk factor for ulcer development in the equine stomach; however, the exact pathogenesis for this has not been established. Objective: To investigate the effect of 3 environmental situations (grass paddock, stall alone or stall with adjacent companion) on pH in the proximal and the ventral stomach. Methods: Six horses with permanently implanted gastric cannulae were used in a randomised, cross-over, block design. Each horse rotated through each of three 24 h environmental situations. Horses remained on their normal diet (grass hay ad libitum and grain b.i....
Ragnarsson S, Jansson A.The aim of the present study was to compare digestibility and metabolic response in Icelandic and Standardbred horses fed two grass haylages harvested at different stages of maturity. Six horses of each breed were used in a 24-day change-over design. A total collection of faeces was made on days 15-17 and 22-24. Blood samples were collected on day 24 of each period and analysed for total plasma protein (TPP), plasma urea, non-esterified fatty acids, cortisol and insulin concentration. There were no differences in digestibility coefficients of crude protein, neutral detergent fibre or energy be...
Connysson M, Essén-Gustavsson B, Lindberg JE, Jansson A.A higher forage allowance to athletic horses might be an alternative to increase health and the gut fluid reservoir. However, more forage might increase bodyweight (bwt) and could therefore be a limitation during competition. Objective: To investigate the effect of a forage-only diet (FD) compared to a 50:50 (dry matter basis) forage:oats diet (OD) on bwt, plasma protein concentration and some metabolic plasma parameters during 12 h of feed deprivation. Methods: Twelve adult Standardbred horses in training were used. The 2 diets were fed in 2 experimental periods of 3 weeks each in a crossover...
Clauss M, Loehlein W, Kienzle E, Wiesner H.In order to test the suitability of the horse as a nutritional model for elephants, digestibility studies were performed with six captive Asian elephants on six different dietary regimes, using the double marker method with acid detergent lignin as an internal and chromium oxide as an external digestibility marker. Elephants resembled horses in the way dietary supplements and dietary crude fibre content influenced digestibility, in calcium absorption parameters and in faecal volatile fatty acid composition. However, the absolute digestibility coefficients achieved for all nutrients are distinc...
Zhao K, Chi Y, Shen X.As a consequence of contracted and fenced grassland, the incidence of edema pathema in the Hequ horse is rising. The main pathological symptoms are edema, emaciation, anemia, heterophilia, inappetence, and dyskinesia. To study the cause of edema disease in Hequ horse, the Hequ horse farm with a high incidence was chosen as the experimental pasture, and the Azi husbandry experimental station without edema disorder was the control pasture. The research methods in this paper are included: (1) The mineral contents in soil, forage, blood, and liver were analyzed. (2) Routine parameters and biochemi...
Franz R, Soliva CR, Kreuzer M, Hummel J, Clauss M.It is assumed that small herbivores produce negligible amounts of methane, but it is unclear whether this is a physiological peculiarity or simply a scaling effect. A respiratory chamber experiment was conducted with six rabbits (Oryctolagus cuniculus, 1.57±0.31 kg body mass) and six guinea pigs (Cavia porcellus, 0.79±0.07 kg) offered grass hay ad libitum. Daily dry matter (DM) intake and DM digestibility were 50±6 g kg⁻⁰·⁷⁵ d⁻¹ and 55±6% in rabbits and 59±11 g kg⁻⁰·⁷⁵ d⁻¹ and 61±3% in guinea pigs, respectively. Methane production was similar for both species (0.2...
Pearson RA, Archibald RF, Muirhead RH.Four donkeys and four ponies were fed molassed dehydrated alfalfa or oat straw, either ad libitum or restricted to about 70% ad libitum intake in a Latin-square design for four periods of 21 d. Measurements of apparent digestibility and gastrointestinal transit time were made on the last 7 d of each period. When the forages were provided ad libitum, all animals ate significantly more of the alfalfa than of the oat straw. Ponies consumed significantly more of both diets per unit live weight than donkeys. Higher apparent digestibilities of dietary DM, energy and fibre fractions were seen in donk...
Marliani G, Sprocatti I, Schiavoni G, Bellodi A, Accorsi PA.The increasing interest in animal welfare and the knowledge of equine physiological and ethological needs have led to the development of different types of horses' management and housing systems. The research presented here aimed to assess the daytime activity budget of horses. Focal animal sampling was used as an observational sampling method, and the five animals were observed for a total of 9920 minutes in the paddock and inside the stall. The results showed that horses spent most of the daytime in foraging behaviors, followed by resting behaviors, and locomotion. Social behaviors (s.e. al...
