Feeding trials in horses are controlled studies designed to evaluate the effects of different diets or nutritional strategies on equine health and performance. These trials systematically assess various dietary components, such as protein, fiber, vitamins, and minerals, to determine their impact on parameters like weight gain, digestive efficiency, and overall well-being. Participants in these studies may include horses of different breeds, ages, and activity levels to provide comprehensive insights. The data collected from feeding trials contribute to the development of evidence-based dietary recommendations and nutritional guidelines. This page compiles peer-reviewed research studies and scholarly articles that investigate the methodologies, outcomes, and implications of feeding trials in equine nutrition.
Ghajar SM, McKenzie H, Fike J, McIntosh B, Tracy BF.Introduced cool-season grasses are dominant in Virginia's grasslands, but their high digestible energy and nonstructural carbohydrate (NSC) levels pose a risk for horses prone to obesity and laminitis. Native warm-season grasses (NWSGs) have lower digestible energy and NSC levels that may be more suitable for horses susceptible to laminitis. Although NWSGs have desirable characteristics, they are novel forages for horses. Little is known about NWSG intake or potential toxicity to horses or how grazing by horses may affect NWSG swards. The overall objectives of this research were to 1) assess v...
Cappai MG, Taras A, Cossu I, Cherchi R, Dimauro C, Accioni F, Boatto G, Deroma M, Spanu E, Gatta D, Dall'Aglio C, Pinna W.Trace element status and metabolic milieu are sometimes overlooked in common veterinary clinical practice across animal species. The evaluation of requirements of trace elements, in fact, may be useful to prevent the perturbation of tissue-specific metabolic impair. In particular, essential trace elements in the diet play key roles within sub-cellular metabolic patterns with macro effects at the systemic level, like blood cell stability and semen quality. This effect was studied in breeding stallions, in which semen quality and haemogram are important for reproduction. A case-control feeding t...
Jacobs RD, Gordon MBE, Vineyard KR, Keowen ML, Garza F, Andrews FM.Low gastric pH for extended periods of time can increase the risk of gastric ulceration in horses. Therefore, nutritional interventions that buffer stomach acid may be helpful to decrease ulcer risk. The objective of this trial was to evaluate whether the incorporation of calcified Lithothamnion corallioides and Phymatolithon calcareum (Calmin; Celtic Sea Minerals, Cork, Ireland) into an equine ration would buffer equine gastric juice. Nine mature, Thoroughbred-cross horses, including 6 geldings and 3 mares (524 ± 49 kg) were housed in stalls and fed 2 kg/day of a texturized concentrate (Pu...
DeBoer M, Konop A, Fisher B, Martinson K.Thermoregulation is an energy-expensive process, which can be mitigated by blanketing horses in cold climates, potentially preventing weight loss or leading to decreased feed intake. The objective of this study was to evaluate feed intake, body weight (BW), and body condition scores (BCSs) in blanketed and nonblanketed horses. In October 2019, 16 mature adult horses were blocked by breed and BCS and randomly assigned to a blanketed (n = 8) or nonblanketed (n = 8) treatment; blankets were placed. Data were collected in December 2019 and January 2020 in River Falls, Wisconsin. During the study...
Francis JM, Neander CR, Roeder MJ, Perry EB.Palatants may be added to equine feed and medication either during or after manufacturing to enhance product acceptance. Prior studies have examined a variety of palatants but results have been limited and inconsistent. Therefore, the objective of this research was to evaluate topically applied oil-based palatants on feeding preferences in horses. Stock-type horses (n = 10) were used in this paired preference test across a two-phase study. Phase one compared six palatants (banana, anise, peppermint, apple, spearmint, and orange) to a control (corn oil), whereas phase two compared preference a...
Kaiser-Thom S, Hilty M, Gerber V. Recent evidence suggests that an altered intestinal microbiota, specifically a reduction of bacterial diversity or a shift in microbial composition, is associated with the development of hypersensitivity disorders in humans, but this is unknown for horses. In this study we hypothesized that horses affected by either Culicoides hypersensitivity or severe equine asthma or both show a decreased diversity of their intestinal microbiota. We also investigated environmental effects. Rectal swab samples of a total of 140 horses were collected and the owners completed a detailed questionnaire about th...
Fehlberg LK, Lattimer JM, Vahl CI, Drouillard JS, Douthit TL.Calcium salts of fatty acids (CSFAs) frequently are fed to ruminants, but their fate in the equine digestive system is unknown. The purpose of this study was to compare Enertia s/f, a proprietary CSFAs, and soybean (SB) oil with respect to impact on apparent total tract nutrient digestion and cecal fermentation parameters in horses. Eight cecally cannulated Quarter Horses were used in a crossover design in which horses consumed a diet for 32 d consisting of 1.5% body weight (BW) (as-fed) smooth bromegrass hay and 0.5% BW (as-fed) pelleted concentrate containing 4.9% CSFAs or 4.1% SB oil. Fecal...
Hansen TL, Chizek EL, Zugay OK, Miller JM, Bobel JM, Chouinard JW, Adkin AM, Skurupey LA, Warren LK.Bermudagrass (Cynodon dactylon) and other warm-season grasses are known for their increased fiber concentrations and reduced digestibility relative to cool-season grasses and legumes. This study investigated the digestive characteristics and passage kinetics of three maturities of Coastal bermudagrass hay. A 5 × 5 Latin square design experiment was used to compare the digestion of five hays: alfalfa (Medicago sativa, ALF), orchardgrass (Dactylis glomerata, ORCH), and Coastal bermudagrass harvested at 4 (CB 4), 6 (CB 6), and 8 weeks of regrowth (CB 8). Horses were fed cobalt-ethylenediaminetet...
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...
Jordan KV, Drouillard JS, Douthit TL, Lattimer JM.Eight cecally cannulated Quarter Horses were used in a replicated 4 × 4 Latin square experiment conducted in four 14-d periods to determine effects of sodium caseinate (casein) on hindgut fermentation and fiber digestion. During each period, horses were assigned to one of four treatments consisting of control (water; CON), 0.125 g casein/kg BW (LOW), 0.25 g casein/kg BW (MED), or 0.5 g casein/kg BW (HI). Casein was solubilized in 800 mL water and dosed directly into the cecum at 0700 and 1900 hours using a metal dosing syringe. Smooth Bromegrass hay (CP 8.50%), water, and salt were provided a...
Turcott-White SK, Nielsen BD, Robison CI, Skelly CD, Rosenstein DS, Pritchard A, Herdt T.The objective of this study was to compare the feed intake and the apparent digestibilities of three different diets varying in concentrate-to-roughage ratios in weanling horses (n = 24) at 5 and 8 months of age. Horses were stratified by breed, gender, birth date and body weight and assigned to one of three dietary treatments containing the following concentrate-to-roughage ratios on an as-fed basis: 70:30 (High Con), 50:50 (Equal) and 30:70 (Low Con). All horses were fed their respective diets for a 10-day adaptation period and a 4-day collection period at 5 and 8 months. There were no d...
Latham CM, Wagner AL, Urschel KL.The objective of this study was to examine markers of whole-body and muscle protein metabolism in aged horses fed a diet typical for North American aged horses, supplemented with amino acids. In a replicated Latin square design, six aged horses (20 ± 1.1 years) were studied while receiving each of three isocaloric, isonitrogenous diets, a control treatment concentrate (CON; 100 mg/kg BW day lysine, 84 mg kg day threonine, 51 mg kg day methionine), LYS/THR (134 mg kg BW day lysine, 110 mg kg BW day threonine, 52 mg kg BW day methionine) and LYS/THR/MET (132 mg kg BW da...
Healey K, Lawlor C, Knox MR, Chambers M, Lamb J, Groves P.A series of placebo-controlled trials were conducted in horses, cattle and goats in different seasons and bioclimatic regions of New South Wales and Queensland, Australia, to evaluate the ability of BioWorma®, a feed supplement containing the spores of Duddingtonia flagrans IAH 1297, to reduce the larval development of parasitic gastrointestinal nematodes (GIN) and their subsequent migration from faeces onto the surrounding pasture. In each trial, faeces were collected from animals harbouring a burden of nematode parasites following a period of supplementation with a placebo and again after s...
da Silva Inácio DF, de Rezende ASC, Melo MM, Quintão Lana ÂM, Prado Silva RH, de Jesus Mendes L, de Paula Gonçalves Reis L, Maruch S, Ralston SL.Young horses reach nearly 90% of their final height in the first year of life. However, to achieve their genetic potential, it is necessary to receive adequate nutrition during this period of rapid growth. The objective of this study was to evaluate the effect of supplementation of sorghum silage during a period of limited pasture forage availability, on the body development, and health of Mangalarga Marchador (MM) weanling fillies. Fourteen healthy MM 6-month-old fillies were randomly assigned to one of two groups: GS (consuming silage) and GH (consuming grass hay (Cynodon spp) in addition to...
Williams T, Rude B, Liao S, Mochal-King C, Nicodemus M.The objective of this study was to observe how fat incorporated into an equine forage-based diet through supplementation altered levels of plasma glucose, insulin and fatty acids. Five Shetland/Hackney cross pony mares were fed alfalfa pellet diets top dressed with commercially available vegetable oil (blend of soya bean, canola and corn oils) at 0%, 5%, 10% or 15% of diet. Ponies were randomly assigned one of four diets to start, with a 14-day adjustment period between transitioning to another one of the four diets. Ponies were gradually adapted to the new diet within the 14-day period before...
Bochnia M, Boesel M, Bahrenthien L, Wensch-Dorendorf M, Zeyner A.The aim of the study was to compare diverse feed intake patterns in sport ponies and warmblood-type horses after feeding iso-energetic amounts of three different concentrates: a pelleted fibre-rich mixed feed (PF), a muesli feed (MF) and semicrushed oat grains (OG). Four sport ponies and six warmblood-type horses received the concentrates and meadow hay according to maintenance (0.52 MJ metabolizable energy (ME) kg body weight (BW) /day). Both breeds were allocated at random to three groups and received once daily for 8 days either OG (1 g starch/kg BW/meal) or iso-energetic quantities of ...
Schaafstra FJWC, van Doorn DA, Schonewille JT, van Riet MMJ, Visser P, Blok MC, Hendriks WH.Methodological aspects of digestibility measurements were studied in four Welsh pony geldings consuming haylage-based diets with increasing proportions of a pelleted concentrate according to a 4×4 Latin square design experiment. Ponies were fed four experimental, iso-energetic (net energy (NE) basis) diets (i.e. 22 MJ NE/day) with increasing proportions of a pelleted concentrate (C) in relation to haylage (H). The absolute amounts of diet dry matter fed per day were 4.48 kg of H (100H), 3.36 and 0.73 kg of H and C (75H25C), 2.24 and 1.45 kg of H and C (50H50C) and 1.12 and 2.17 kg of H and C ...
Mastellar SL, Coleman RJ, Urschel KL.Lysine has been reported as the first limiting amino acid in typical equine diets. Indicator amino acid oxidation (IAAO) has become the standard method for determining amino acid requirements in other species, but prior to this study, it has not been used to determine equine requirements. The aim of this study was to evaluate whole body protein synthesis and plasma and muscle amino acid concentrations in response to graded levels of lysine intake in yearling horses. Six Thoroughbred colts (358 ± 5 kg) were fed each of six treatment lysine intakes ranging from 76 to 136 mg/kg body weig...
Schaafstra FJ, van Doorn DA, Schonewille JT, Wartena FC, Zoon MV, Blok MC, Hendriks WH.Methodological aspects of digestibility measurements of feedstuffs for equines were studied in four Welsh pony geldings consuming four grass-hay diets in a 4 × 4 Latin square design. Diets contained either a low (L), medium (M), high (H), or very high (VH) ADF content (264, 314, 375, or 396 g·kg DM, respectively). Diets were supplemented with minerals, vitamins, and TiO (3.9 g Ti·d). Daily feces excreted were collected quantitatively over 10 consecutive days and analyzed for moisture, ash, ADL, AIA, and titanium (Ti). Minimum duration of total fecal collection (TFC) required for an accurate...
Bruynsteen L, Moons CP, Janssens GP, Harris PA, Vandevelde K, Lefère L, Duchateau L, Hesta M.Due to the high prevalence of obesity in some horses and ponies (especially in the leisure horse sector), effective and safe weight loss strategies are required. The present study evaluated the effect of two different energy restriction rates on physical, morphometric and welfare parameters in 18 obese (body condition score [BCS] 7-9/9) Shetland geldings. The trial was divided into three periods: (1) a 4 week adaptation period, during which the maintenance energy intakes to maintain a stable obese bodyweight were determined (100% MERob); (2) a 16.5-week weight loss period during which the poni...
John J, Roediger K, Schroedl W, Aldaher N, Vervuert I.Almost all foals develop transient diarrhoea within the first weeks of life. Studies indicated different viral, bacterial, and parasitic causes, such as rotavirus, Clostridium perfringens, Escherichia coli, and Cryptosporidium are discussed. But little is known about the development of intestinal microflora in foals. The present study investigated whether the supplementation with Bacillus cereus var. toyoi would modify the developing intestinal microflora and consequently reduce diarrhoea in foals. From birth, the foals were randomly assigned to three treatment groups: placebo (10 mL isotonic...
van Doorn DA, Schaafstra FJ, Wouterse H, Everts H, Estepa JC, Aguilera-Tejero E, Beynen AC.This study addresses the question of whether feeding rations rich in P for a period of up to 42 d induces a positive P balance in adult ponies. Biochemical bone markers and parathyroid hormone (PTH; intact as well as whole PTH) were measured to obtain clues as to the effect of P loading on bone metabolism. The experiment had a Latin square design. Each feeding period lasted 42 d, and there were 2 balance trials (ECP1 and ECP2) within each feeding period. Each balance trial lasted 10 d (ECP1: d 11 to 21; ECP2: d 33 to 42). Six ponies aged 2.5 to 7 yr were fed a control diet that provided P and ...
Jensen RB, Austbø D, Bach Knudsen KE, Tauson AH.A total of four diets with different carbohydrate composition were investigated in a 4×4 Latin square design experiment with four Norwegian Coldblooded trotter horses. The objective of the present study was to increase the fermentable fibre content and reduce the starch intake of the total ration obtained by partly substituting mature hay and barley with sugar beet pulp (SBP), a soluble fibre source. The diets investigated were hay only (HAY), hay (85% of dry matter intake (DMI)) and molassed SBP (15% of DMI) (SBP), hay (68% of DMI) and barley (32% of DMI) (BAR), and hay (68% of DMI), barley ...
Goachet AG, Harris P, Philippeau C, Julliand V.This study aimed at evaluating, in previously inactive Standardbreds horses, the effect of 5 weeks of an exercise training programme on nutrient digestibility and faecal fermentative parameters (FFPs). As an increase in digestibility had previously been reported in trained endurance horses, we hypothesized that similar results would be found in horses being trained for other types of exercise on a different type of diet. After 3 weeks of dietary adaptation, a digestibility trial (DT1) was undertaken, over 3 days, in eight untrained Standardbreds with a fresh faecal sample being collected on th...
Redgate SE, Cooper JJ, Hall S, Eady P, Harris PA.Choice feeding is often used to investigate an animal's nutritional requirements and dietary preferences. A problem with this approach is that animals with long gut transit times, such as the horse, may find it difficult to associate a chosen food with its nutritional consequence when alternative foods are presented simultaneously. One solution is to present foods singly for a period of time before a simultaneous choice session to allow the development of learned associations. This method was used to determine if horse's voluntary intake and feeding behavior was influenced by the macronutrient...
De Marco M, Peiretti PG, Miraglia N, Bergero D.The aim of this study was to assess the apparent digestibility of broken rice using total collection of feces and the pepsin-cellulase in vitro technique to provide updated and more accurate digestion coefficients for this by-product when fed to horses. The in vivo digestibility trial was consecutively performed, using five adult geldings, weighing 555.6 kg on average. First, hay was given as the only feedstuff, while second, the experimental diet consisted of the same hay plus broken rice at a forage-to-concentrate ratio of 70/30 (on dry matter (DM) basis). Feces were collected over 6 days pr...
Longland AC, Barfoot C, Harris PA.The effects of different water-soaking treatments on removal of water-soluble carbohydrates (WSC), WSC constituents and protein from four UK hays were determined. Hays were soaked in water for up to 16 hours at mean temperatures of 8°C, 16°C, in hot tap water (initially 49°C) or agitated and rinsed in clean water at 16°C. Initial hay WSC contents ranged from 154 to 216 g/kg dry matter. Losses of WSC from hays after 16 hours soaking at 8°C, 16°C, 16°C plus agitation and 49°C averaged 28, 46, 49 and 44 per cent, respectively. Corresponding percentage losses of fructan were 16, 37, 39 and...
Gordon ME, Edwards MS, Sweeney CR, Jerina ML.The objective of this study was to test the hypothesis that an equine diet formulated with chelated trace minerals, organic selenium, yeast culture, direct-fed microbials (DFM) and Yucca schidigera extract would decrease excretion of nutrients that have potential for environmental impact. Horses were acclimated to 100% pelleted diets formulated with (ADD) and without (CTRL) the aforementioned additives. Chelated sources of Cu, Zn, Mn, and Co were included in the ADD diet at a 100% replacement rate of sulfate forms used in the CTRL diet. Additionally, the ADD diet included organic selenium yeas...
Winsco KN, Coverdale JA, Wickersham TA, Lucia JL, Hammer CJ.Thirty pregnant mares (538 to 695 kg BW; 4 to 19 yr of age) were used to evaluate the effects of plane of nutrition on DMI of hay and mare performance (BW, BCS, and rump fat) during the last third of pregnancy. Mares were divided into 4 blocks by their expected foaling date and randomly assigned within block to either a hay or concentrate plus hay diet (concentrate fed at 0.75% BW, as-fed basis) with 15 mares per treatment. Treatments began 110 d before expected foaling date (230 d of gestation) and terminated at parturition. Mares were housed by block and allowed ad libitum access to coastal ...
van Doorn DA, Everts H, Wouterse H, Beynen AC.Availability of phytate-bound P as influenced by supplemental phytase was studied in eight horses consuming four diets in a 4 x 4 Latin square design experiment. The treatments were a control (containing a low P level, 18.4 g/d) and three high-P diets. These diets contained P as monocalcium phosphate (MCP; 43.7 g/d), myoinositol hexakisphosphate in the form of wheat and rice bran (MIHP; 41.8 g/d), or MIHP with microbial phytase (MIHPP; 42.5 g/d). The proportions of phytate-bound P were 3, 1, 55, and 56% for the control, MCP, MIHP, and MIHPP, respectively. The MIHPP diet was supplemented with 3...
Johnson AL, Divers TJ, Freckleton ML, McKenzie HC, Mitchell E, Cullen JM, McDonough SP.Fourteen horses at a boarding stable in Virginia were diagnosed with hepatic disease and locally grown hay was implicated as the cause. Objective: Panicum dichotomiflorum, the predominant grass species in the hay, is hepatotoxic to horses. Methods: Naturally occurring cases were adult horses of various breeds. Two healthy adult horses and 2 healthy adult sheep were used in feeding trials. Methods: Blood and liver specimens collected from affected animals during the outbreak were analyzed. Some of the affected animals were treated supportively; the main intervention was hay withdrawal. Feeding ...
Steelman SM, Michael-Eller EM, Gibbs PG, Potter GD.Energy is an essential nutrient for all horses, and it is especially important in performance horses, pregnant and lactating mares, and young growing horses. A negative energy balance in horses such as these may result in unsatisfactory performance, decreased fertility, or slow growth. Therefore, ensuring adequate energy intake is an important aspect of the nutritional management of the equine. This study was undertaken to investigate the effects of feeding large, carbohydrate-rich, concentrate meals on the satiety-inducing hormone, leptin. Three groups of yearling horses were rotated through ...
Witham CL, Stull CL.To examine metabolic responses of chronically starved horses to refeeding with 3 isoenergetic diets. Methods: Uncontrolled clinical trial. Methods: 22 mature mixed-breed horses that were emaciated but otherwise clinically normal. Methods: Horses were fed 1 of 3 diets: alfalfa hay, oat hay, or a combination diet of half oat hay and half commercially prepared ration. Digestible energy of diets was gradually increased throughout the refeeding period. One pre- and 4 postprandial blood samples were obtained daily, and analyses included RBC count, Hct, and determination of hemoglobin, glucose, insul...
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...
Franzan BC, Coelho IDS, de Souza MT, Santos MMM, de Almeida FQ, Silva VP.Sudden changes in horses' diet have been previously associated with gastrointestinal disease. This study evaluated the effects of a sudden change of diet composed exclusively of Coastcross hay (CHD) to a complete extruded diet (CED) on the fecal microbiome of horses. A completely randomized design with repeated measurements was used. The study started with eight adult horses randomly split into group A, fed with CHD, and group B, fed with CED. After 34 days of diet adaptation, the diets were abruptly changed between the groups. Fecal samples were collected at 0, 24, and 96 hours after the diet...
Nation PN.Trifolium hybridum (alsike clover) has been implicated as the cause of two diseases of the horse. One of these is photosensitivity, of which alsike clover is only one of a number of presumed causal agents. The other is a fatal syndrome which is known as "alsike clover poisoning" and which is manifest by progressive loss of condition, signs of hepatic failure, and varying degrees of neurological impairment. The underlying lesion of alsike clover poisoning is fibrosis and proliferation of the biliary tree. The experimental evidence implicating alsike clover as the cause of this syndrome comes en...
Geelen SN, Jansen WL, Geelen MJ, Sloet van Oldruitenborgh-Oosterbaan MM, Beynen AC.The hypothesis tested was that dietary fat, when compared with an isoenergetic amount of non-structural carbohydrates, stimulates lipolysis in adipose tissue and also stimulates the fatty-acid oxidative capacity in skeletal muscle from horses. Six adult horses were fed a high-fat, glucose or starch containing diet according to a 3 x 3 Latin square design with feeding periods of three weeks. The diets were formulated so that the intake of soybean oil versus either glucose or corn starch were the only variables. In accordance with previous work, whole plasma triacylglycerol (TAG) concentration d...
Kalantari RK, Rouzbehan Y, Fazaeli H, Direkvandi E, Salem AZM.The aim of this study was to investigate, the effect of different levels of concentrates and grain processing on feeding behavior, nutrient digestibility, fecal pH and blood metabolites in the horse. Sixteen 5 to 11 years old Turkmen horses with an initial body weight 433±50 kg were used in this experiment based on completely randomized design. Four treatments were studied, in three treatments were used 20, 25 and 30% of concentrate containing processed grains (A20, A25 and A30, respectively), and in one treatment was used 25% of concentrate containing whole grain (B25). The amount of feed in...
van Doorn DA, Schaafstra FJ, Wouterse H, Everts H, Estepa JC, Aguilera-Tejero E, Beynen AC.This study addresses the question of whether feeding rations rich in P for a period of up to 42 d induces a positive P balance in adult ponies. Biochemical bone markers and parathyroid hormone (PTH; intact as well as whole PTH) were measured to obtain clues as to the effect of P loading on bone metabolism. The experiment had a Latin square design. Each feeding period lasted 42 d, and there were 2 balance trials (ECP1 and ECP2) within each feeding period. Each balance trial lasted 10 d (ECP1: d 11 to 21; ECP2: d 33 to 42). Six ponies aged 2.5 to 7 yr were fed a control diet that provided P and ...
Hansen TL, Chizek EL, Zugay OK, Miller JM, Bobel JM, Chouinard JW, Adkin AM, Skurupey LA, Warren LK.Bermudagrass (Cynodon dactylon) and other warm-season grasses are known for their increased fiber concentrations and reduced digestibility relative to cool-season grasses and legumes. This study investigated the digestive characteristics and passage kinetics of three maturities of Coastal bermudagrass hay. A 5 × 5 Latin square design experiment was used to compare the digestion of five hays: alfalfa (Medicago sativa, ALF), orchardgrass (Dactylis glomerata, ORCH), and Coastal bermudagrass harvested at 4 (CB 4), 6 (CB 6), and 8 weeks of regrowth (CB 8). Horses were fed cobalt-ethylenediaminetet...
Cí·¯ord D, Woodhead A, Muirhead R.The objective was to evaluate the nutritive value of short-cutting cycle, high temperature-dried (SCCHTD) alfalfa compared to timothy hay. This was achieved by carrying out 4 x 4 Latin Square digestibility trial using 4 Thoroughbred (one three-quarter Thoroughbred) horses (mean liveweight, 531 kg). The four dietary treatments were 0AA (timothy hay only), 33AA (0.33 alfalfa: 0.67 timothy hay), 67AA (0.67 alfalfa: 0.33 timothy hay) and 100AA (alfalfa only). Digestibility data were obtained by using acid-insoluble ash to estimate apparent digestibility coefficients of nutrients. Rate of passage o...
Ordakowski AL, Kronfeld DS, Holland JL, Hargreaves BJ, Gay LS, Harris PA, Dove H, Sklan D.Dry matter intake (DMI), dry matter digestibility (DMD), and fecal output (FO) are difficult to measure directly in the field, and indirect methods using external and internal markers have thus been developed. An experiment was conducted consisting of two digestion trials with two periods in each trial to examine the use of five odd-chain alkanes (C25 to C33) of plant cuticular wax as internal markers to estimate DMD of hay or hay plus concentrate diets in horses. Eight mature Thoroughbred geldings were housed in 4- x 4-m stalls and randomly assigned to one of two mixed grass/legume hays (Diet...
Hansen RA, Savage CJ, Reidlinger K, Traub-Dargatz JL, Ogilvie GK, Mitchell D, Fettman MJ.An 18-week feeding trial was performed to investigate the effects of an omega-3 (n-3) fatty acid-enriched ration on plasma fatty acid concentrations and platelet aggregation in healthy horses. Flaxseed oil served as the source of the n-3 fatty acid alpha-linolenic acid (ALA). Twelve horses were fed dietary maintenance requirements using a complete pelleted ration (80%) and timothy grass hay (20%) for a 2-week acclimation period before being randomly assigned either to a treatment (group 1) or control (group 2) group. Group 2 horses (n = 6) were fed the diet described in the acclimation period,...
Jansen WL, Geelen SN, van der Kuilen J, Beynen AC.The aim of the present study was to establish whether the inhibitory effect of fat feeding on fibre digestion has been underestimated due to the substitution of fat for corn starch. A high fat intake has been shown to lower total intestinal tract apparent digestibility of crude fibre in horses but, since fat was substituted for nonstructural carbohydrates, including starch, the specific effect of fat could not be ascertained. The possibility could not be excluded that starch also inhibits fibre digestibility, so that the fat effect observed earlier would have been underestimated. In this study...
Jose-Cunilleras E, Taylor LE, Hinchcliff KW.Muscle glycogen synthesis depends on glucose availability. This study was undertaken to determine the glycemic and insulinemic response of horses to equal amounts of hydrolyzable carbohydrates (starch and sugar) in the form of one of three grain meals or intragastric administration of a glucose solution. In a randomized crossover design, seven horses were fed each of three grain meals (cracked corn, steamed oat groats, or rolled barley) or were infused intragastrically with glucose solution at 2 g of hydrolyzable carbohydrate (starch plus sugar) per kilogram of BW. The quantity of hydrolyzable...
Laut JE, Houpt KA, Hintz HF, Houpt TR.In order to determine if horses will increase their intake in response to caloric dilution, four pony geldings were fed ad lib a mixed grain diet either undiluted (3.4 Mcal/kg of digestible energy) or diluted (wt/wt) with 25% sawdust (2.6 Mcal/kg) or with 50% sawdust (1.7 Mcal/kg). The mean daily caloric intake was 17,457 kcal (3.4 Mcal diet), 17,546 kcal (2.6 Mcal diet) and 12,844 kcal (1.7 Mcal). The mean time spent eating was 246 (3.4 Mcal), 351 (2.6 Mcal), and 408 (1.7 Mcal) minutes/day. Meal size increased and meal frequency decreased with increasing dilution. The median long survivorship...
Mäenpää PH, Pirhonen A, Koskinen E.The effects of feeding two different vitamin-mineral concentrates on serum levels of vitamins A, E and D and some growth indicators were examined in 30 pregnant mares and 30 foals. One concentrate contained vitamins A and E and the other did not. Both contained vitamin D3. No differences (P greater than .05) in serum levels of retinol and alpha-tocopherol were observed between the feeding groups in the mares, whereas in the weanlings serum levels of dietary vitamins A and E increased (P less than .01) during late winter and early spring. However, the values did not increase to levels found in ...
Jansen WL, van der Kuilen J, Geelen SN, Beynen AC.The hypothesis tested was that the intake of extra fat at the expense of an isoenergetic amount of nonstructural carbohydrates reduces fibre utilisation in horses. In a crossover trial with feeding periods of 42 days each, 6 mature trotting horses (age 4-12 years, bodyweight 340-476 kg) were given either a control or test diet. The test concentrate was formulated to contain 37% of net energy in the form of soybean oil. The control concentrate contained an isoenergetic amount of corn starch plus glucose. The concentrates were fed in combination with the same amount of hay so that the control an...
Winsco KN, Coverdale JA, Wickersham TA, Shelton JL.Twenty-four Quarter Horse weanlings (120 ± 10 d) were blocked by age into 4 groups (n=6) for a 56-d trial to evaluate the influence of dietary Met concentration on growth and N balance. Weanling horses were housed by block and individually fed concentrates twice daily at 1.75% BW (as-fed basis). Weanling horses were randomly assigned to 1 of 4 concentrate treatments: basal (0.20 Met), basal + 0.03% Met (0.23 Met), basal + 0.07% Met (0.27 Met), and basal + 0.11% Met (0.31 Met). Diets were formulated to be isonitrogenous and isocaloric and contained equal amounts of Lys and Thr. Coastal bermuda...
Cappai MG, Taras A, Cossu I, Cherchi R, Dimauro C, Accioni F, Boatto G, Deroma M, Spanu E, Gatta D, Dall'Aglio C, Pinna W.Trace element status and metabolic milieu are sometimes overlooked in common veterinary clinical practice across animal species. The evaluation of requirements of trace elements, in fact, may be useful to prevent the perturbation of tissue-specific metabolic impair. In particular, essential trace elements in the diet play key roles within sub-cellular metabolic patterns with macro effects at the systemic level, like blood cell stability and semen quality. This effect was studied in breeding stallions, in which semen quality and haemogram are important for reproduction. A case-control feeding t...
Schaafstra FJ, van Doorn DA, Schonewille JT, Wartena FC, Zoon MV, Blok MC, Hendriks WH.Methodological aspects of digestibility measurements of feedstuffs for equines were studied in four Welsh pony geldings consuming four grass-hay diets in a 4 × 4 Latin square design. Diets contained either a low (L), medium (M), high (H), or very high (VH) ADF content (264, 314, 375, or 396 g·kg DM, respectively). Diets were supplemented with minerals, vitamins, and TiO (3.9 g Ti·d). Daily feces excreted were collected quantitatively over 10 consecutive days and analyzed for moisture, ash, ADL, AIA, and titanium (Ti). Minimum duration of total fecal collection (TFC) required for an accurate...
Araújo JA, Curcio B, Alda J, Medeiros RM, Riet-Correa F.Two outbreaks of Hypochaeris radicata-induced Australian stringhalt involving two farms and seven horses from southern Brazil are reported here. Subsequently, the disease was experimentally reproduced in a feeding trial with one colt fed H. radicata from the suspect paddocks. Fresh H. radicata was fed to the experimental animal for 50 days at an average daily dosage of 9.8 kg. Initially, the plant was collected from the paddock where the clinical disease occurred and was fed for 19 consecutive days producing mild clinical signs. However, on days 20-23 fresh plant was collected from a neighbori...
van Doorn DA, van der Spek ME, Everts H, Wouterse H, Beynen AC.Literature data show conflicting results on the effect of feeding high calcium (Ca) levels on phosphorus (P) digestibility in ponies. None of the studies reported involved a dose response as to the effect of Ca intake on apparent P digestibility while keeping P intake constant. Thus, the influence of high dietary Ca level on apparent P digestibility was studied in balance trials by feeding six mature ponies three different Ca levels against a constant P intake. The ponies received 148, 316 and 535 mg Ca/kg BW/day with the low, intermediate and high Ca diet. Phosphorus intake was approximately ...
Bochnia M, Boesel M, Bahrenthien L, Wensch-Dorendorf M, Zeyner A.The aim of the study was to compare diverse feed intake patterns in sport ponies and warmblood-type horses after feeding iso-energetic amounts of three different concentrates: a pelleted fibre-rich mixed feed (PF), a muesli feed (MF) and semicrushed oat grains (OG). Four sport ponies and six warmblood-type horses received the concentrates and meadow hay according to maintenance (0.52 MJ metabolizable energy (ME) kg body weight (BW) /day). Both breeds were allocated at random to three groups and received once daily for 8 days either OG (1 g starch/kg BW/meal) or iso-energetic quantities of ...
Ott EA, Kivipelto J.Thoroughbred and Quarter Horse yearlings (n = 24; 335+/-7 d of age) were used in a 112-d feeding trial to determine whether chromium (Cr) supplementation would alter growth, development, and energy metabolism of growing horses on high-concentrate diets. The horses were assigned at random within breed and gender subgroups to one of four treatment groups: A) basal concentrate; B) basal plus 175 microg of Cr/kg concentrate; C) basal plus 350 microg of Cr/kg concentrate; and D) basal plus 700 microg of Cr/kg concentrate. Chromium was provided via Cr tripicolinate (Prince Agri Products, Quincy, IL)...
Swartzman JA, Hintz HF, Schryver HF.The effects of dietary oxalic acid on absorption, excretion, and retention of calcium was determined in Shetland ponies in 2 experiments. In each experiment, the results of feeding a control diet consisting of oats, molasses, and a complete pelleted horse ration were compared with those of feeding the control diet plus 1% oxalic acid. The diets contained 0.6% calcium in the 1st experiment and 0.45% calcium in the 2nd experiment. Oxalic acid increased the fecal excretion of calcium and decreased calcium absorption. The endogenous fecal excretion of calcium determined in the 1st experiment, usin...
