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.
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 ...
Cordero VV, Cavinder CA, Tedeschi LO, Sigler DH, Vogelsang MM, Arnold CE.Mathematical nutrition models have been developed for beef and dairy cattle to estimate dietary energy intake needed to change BCS. Similar technology has not been used to improve nutrition and feeding strategies for horses. An accurate equine nutrition model may enhance feeding management and reduce the costs of unnecessary overfeeding and promote an optimal level of fatness to achieve reproductive efficiency. The objectives of this study were to develop and evaluate a mathematical nutrition model capable of accurately predicting dietary energy changes to alter BW, rump fat (RF) thickness, an...
Hampson BA, de Laat MA, Monot J, Bailliu D, Pollitt CC.Many domestic horses and ponies are sedentary and obese due to confinement to small paddocks and stables and a diet of infrequent, high-energy rations. Severe health consequences can be associated with this altered lifestyle. Objective: The aims of this study were to investigate the ability of horses to learn to use a dynamic feeder system and determine the movement and behavioural responses of horses to the novel system. Methods: A dynamic feed station was developed to encourage horses to exercise in order to access ad libitum hay. Five pairs of horses (n = 10) were studied using a randomised...
Brinkmann L, Gerken M, Riek A.Outdoor group housing is increasingly recognized as an appropriate housing system for domesticated horses. The objective of this study was therefore to investigate the effect of potential feed shortage in semi-natural horse keeping systems in winter on animal health and welfare. In 10 female Shetland ponies blood concentrations (NEFA, total protein (TP), total bilirubin (TB), beta-hydroxybutyrate (BHB) and thyroxine (T4)), body mass and the body condition score (BCS) were monitored for 7 months including a 4 months period of feed restriction in five of the 10 ponies. Restrictively fed animals ...
Khol-Parisini A, Hellweg P, Razzazi-Fazeli E, Saalmüller A, Strasser A, Tichy A, Zenteke J.The aim of the present study was to investigate the impact of deoxynivalenol (DON) on cellular and humoral immune parameters in horses. A feeding trial using naturally contaminated oats with high (20.2 mg/kg) and low (0.49 mg/kg) levels of DON was conducted. Two groups of five mares were fed 2 kg oats daily with high or low DON levels for two weeks, using a crossover design with a three-week wash-out period. No adverse effects on general health were observed. Only minor diet-related changes in differential blood counts and serum biochemistry were noted. Serum haptoglobin concentration was sign...
De Marco M, Miraglia N, Peiretti PG, Bergero D.Several studies have reported data on comparisons between two methods: the total collection of feces and the internal markers method. The aim of this study was to assess the apparent digestibility of two concentrates and to compare the apparent digestion coefficients using the total collection of feces and acid-insoluble ash (AIA) as the internal marker method. In 2009, six adult geldings aged between 3 and 11 years, with an average weight per trial of 543, 540 and 542 kg, respectively, were used to determine the apparent digestibility by means of three in vivo digestibility trials on hay, hay...
Shepherd ML, Pleasant RS, Crisman MV, Werre SR, Milton SC, Swecker WS.The objective of this study was to determine the effects of high and moderate non-structural carbohydrates (NSC) hay on insulin, glucose, triglyceride, and leptin concentrations in overweight Arabian geldings. Eight adult overweight (average BCS 7 [9-point scale]) Arabian geldings were fed each of two orchardgrass hays, high NSC (18% DM) and moderate NSC (12% DM), in a cross over design during two 28-day periods. Body weight and body condition score assessment along with blood sampling to measure insulin, glucose, leptin, and triglyceride concentrations were performed on days 0, 7, 14, 21 and ...
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...
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...
Earing JE, Cassill BD, Hayes SH, Vanzant ES, Lawrence LM.The objective of this study was to determine if in vitro methodologies developed for the Ankom Daisy(II) incubator could produce accurate estimates of in vivo equine DM digestibility (DMD) and NDF digestibility (NDFD) when equine feces were used as the inoculum source. Four mature geldings were utilized in a 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of dietary treatments (timothy hay, alfalfa hay, timothy hay plus oats, and alfalfa hay plus oats), in which the geldings were individually housed and fed. During each 5-d total fecal collection period, feces were co...
Janis CM, Constable EC, Houpt KA, Streich WJ, Clauss M.It is often assumed that horses chew food more intensively during ingestion than cattle, which - as ruminants - complete part of the mastication during rumination. This has been proposed as a reason for more robust mandibles, larger masseter insertion areas and larger masseter muscles in horses as compared to cattle and other grazing ruminants. In this study, we evaluate results of comparative feeding trials with three horses (338-629 kg) and three cows (404-786 kg), on four different roughages. Ingestion time (s/g dry matter) and chewing intensity (chews/g dry matter) differed among animals w...
Eckert JV, Myer RO, Warren LK, Brendemuhl JH.Mature horses were used to determine apparent DM, OM, NDF, and CP digestibility values of 2 bermudagrass (BG; Cynodon dactylon) hays, Coastal (CB) and Tifton 85 (T85), and Florigraze perennial peanut (PP; Arachis glabrata) hay. In addition, N, Ca, and P balances were determined in horses fed those hays. Five mature Thoroughbred geldings and 1 Quarter Horse gelding (mean initial BW = 542 +/- 37 kg) were used (5 horses for the last period) in a 3 x 3 repeated Latin square design, with 2 horses per hay and 3 adjustment and collection periods. Horses were randomly assigned to pairs and the initial...
Ragnarsson S, Lindberg JE.Eight mature Icelandic geldings were used in an experiment arranged as a change-over design to evaluate the effect of feeding level on the digestibility of a high-energy haylage-only diet. The horses were fed a low feeding level 10.7 g dry matter (DM)/kg body weight (BW) (maintenance) and a high feeding level 18.1 g DM/kg BW (1.5 × maintenance) during two 23 days experimental periods. Total collection of faeces was performed for 6 days at the end of each period to determine the coefficient of total tract apparent digestibility (CTTAD). The CTTAD for DM, organic matter, neutral detergent fibre...
Rosenfeld I, Austbø D.Gastrointestinal retention time may affect digestive processes in the horse. To evaluate the effect of processing of grains on mean retention time in different segments of the gastrointestinal tract, 4 Norwegian Cold-blooded trotters (cecally cannulated, approximately 500 kg of BW) were used. Barley, maize, and wheat were all ground, pelleted, extruded, and micronized to create a total of 12 processed grains. After an adaptation period of 5 d, each horse was given 0.2 kg of Yb-mordanted grain together with their morning meal, which consisted of 2 kg of hay and 1 kg of one of the grains. Fecal ...
Harris P.This article reviews the principles of feeding management for endurance horses. The amount and type of dietary energy (calories) are key considerations in dietary management, because (1) there is evidence that the body condition score, an indicator of overall energy balance, influences endurance exercise performance, and (2) the source of dietary energy (ie, carbohydrate versus fat calories) impacts health, metabolism, and athletic performance. Optimal performance is also dependent on provision of adequate feed, water, and electrolytes on race day.
Clauss M, Lang-Deuerling S, Kienzle E, Medici EP, Hummel J.To test whether mineral recommendations for horses are likely to guarantee adequate mineral provision for tapirs (Tapirus spp.), we investigated the apparent absorption (aA) of macro and micro-minerals in 18 tapirs from five zoological institutions in a total of 24 feeding trials with total faecal collection. Samples of feeds and faeces were analysed for Ca, P, Mg, Na, K, Fe, Cu and Zn. The resulting aA coefficients and the linear relationships of apparently absorbable dietary mineral content to total dietary mineral content (per 100 g dry matter) were compared with data for domestic horses. W...
Vervuert I, Voigt K, Hollands T, C÷¯ord D, Coenen M.The aim of this study was to investigate the effects of feeding oats alone before or after feeding chopped alfalfa or, in admixture with the alfalfa on the glycaemic and insulinaemic responses of horses as well as post-prandial breath hydrogen and methane excretion. Horses were fed in a randomized order, chopped alfalfa as a source of dietary fibre and unprocessed oats as a source of starch. Chopped alfalfa intake was adjusted to a crude fibre intake of 0.5 g/kg bodyweight (BW) per meal and the oats intake was adjusted to a starch intake of 2 g/kg BW per meal. The feeds were offered in three d...
Carmalt JL, Allen A.To investigate potential relationships between cheek tooth occlusal morphology, apparent feed digestibility, and the reduction in feed particle size that occurs during digestion in horses. Methods: Cross-sectional study. Methods: 17 horses of various ages and breeds and either sex. Methods: Horses were fed 1 of 3 hay-based diets ad libitum for 14 days prior to euthanasia; nutrient analysis was performed on samples of each of the 3 diets. At the time of postmortem examination, the head was disarticulated, photographs were taken of the occlusal surfaces of the maxillary and mandibular cheek toot...
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...
Vervuert I, Voigt K, Hollands T, C÷¯ord D, Coenen M.Four horses were randomly fed a diet containing rolled, micronised or extruded barley; the barley intake was adjusted to supply 2 g starch/kg bodyweight per day. During a 10-day acclimatisation period the horses were also fed 1 kg grass hay/100 kg bodyweight per day. Samples of blood and breath were collected at the end of each period after the test meal of barley had been fed after a 12-hour overnight fast. The glycaemic and insulinaemic responses of the horses were measured as an indication of the pre-caecal digestibility of starch, and postprandial breath hydrogen and methane were measured ...
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 (0.52Â MJ metabolizable energy (ME)Â kg body weight (BW) /day). Both breeds were allocated at random to three groups and received once daily for 8Â days either OG (1Â 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...
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...
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...
Hodgson S, Bennett-Skinner P, Lancaster B, Upton S, Harris P, Ellis AD.These studies assessed the pressure forces exerted by horses to extract forage from haynets. Study 1 measured horse posture and pressure in Newtons (10 N = 1 kg Force) exerted on haynets when feeding from either a single (SH) or double layered (DH) haynet (3 kg Hay), hung low or high. Mean and maximum pull forces were higher for the DH vs. SH (DH: 81 ± 2 N, max 156 N; SH: 74 ± 2.9 N, max 121 N; p < 0.01). Horses pulled harder on low (max pull 144 ± 8 N) compared to high (109 ± 8 N; p < 0.05) hung haynets. Mean maximum angles (nose-poll-withers) recorded were 90° ± 9 for SH and 127Â...
Clauss M, Lang-Deuerling S, Kienzle E, Medici EP, Hummel J.To test whether mineral recommendations for horses are likely to guarantee adequate mineral provision for tapirs (Tapirus spp.), we investigated the apparent absorption (aA) of macro and micro-minerals in 18 tapirs from five zoological institutions in a total of 24 feeding trials with total faecal collection. Samples of feeds and faeces were analysed for Ca, P, Mg, Na, K, Fe, Cu and Zn. The resulting aA coefficients and the linear relationships of apparently absorbable dietary mineral content to total dietary mineral content (per 100 g dry matter) were compared with data for domestic horses. W...
Bockisch F, Taubert J, Coenen M, Vervuert I.The German Society of Nutrition Physiology has proposed a new protein evaluation system for horse feeds to estimate pre-cecally digestible crude protein (pcdCP) and amino acids (pcdAA) from chemical properties. A total of 71 feeds for horses were chemically tested and evaluated according to the new protein evaluation system. A feeding trial with eight horses tested whether differences in estimated pcdAA and neutral detergent soluble CP (NDSCP) in the diet were reflected by post-prandial (ppr) kinetics of plasma lysine (Lys) by feeding a complementary feed (control = CTRL) with 1.02 g Lys/100 k...
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...
Goel S, Schumacher J, Lenz SD, Kemppainen BW.Disruption in sphingolipid (SL) metabolism is a biomarker of exposure to fumonisins. The role of altered SL metabolism in the pathogenesis of fumonisin toxicoses is not understood. A 27-d feeding trial in horses compared the toxic effects of 3 strains of Fusarium moniliforme: RRC 415, cultured from corn in MS; AU 2/3, cultured from feed associated with clinical signs of duodenitis-proximal jejunitis (DPJ) in horses in AL; and MRC 826, cultured from corn in South Africa and shown to cause equine leukoencephalomalacia (ELEM). These were cultured on corn and diluted with clean corn and grain mixe...
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...
Hampson BA, de Laat MA, Monot J, Bailliu D, Pollitt CC.Many domestic horses and ponies are sedentary and obese due to confinement to small paddocks and stables and a diet of infrequent, high-energy rations. Severe health consequences can be associated with this altered lifestyle. Objective: The aims of this study were to investigate the ability of horses to learn to use a dynamic feeder system and determine the movement and behavioural responses of horses to the novel system. Methods: A dynamic feed station was developed to encourage horses to exercise in order to access ad libitum hay. Five pairs of horses (n = 10) were studied using a randomised...
Rosenfeld I, Austbø D.Gastrointestinal retention time may affect digestive processes in the horse. To evaluate the effect of processing of grains on mean retention time in different segments of the gastrointestinal tract, 4 Norwegian Cold-blooded trotters (cecally cannulated, approximately 500 kg of BW) were used. Barley, maize, and wheat were all ground, pelleted, extruded, and micronized to create a total of 12 processed grains. After an adaptation period of 5 d, each horse was given 0.2 kg of Yb-mordanted grain together with their morning meal, which consisted of 2 kg of hay and 1 kg of one of the grains. Fecal ...
Grev AM, Hathaway MR, Sheaffer CC, Wells MS, Reiter AS, Martinson KL.Reduced lignin alfalfa (Medicago sativa L.) has the potential to provide a higher-quality forage source for livestock by improving forage digestibility. This study was conducted to evaluate apparent digestibility when feeding reduced lignin and nonreduced lignin alfalfa hay to adult horses, and to examine mean fecal particle size (MFPS) and mean retention time (MRT) between alfalfa forage types. In 2017, reduced lignin ("54HVX41") and nonreduced lignin ("WL355.RR") alfalfa hay was harvested in Minnesota at the late-bud stage. Alfalfa hays were similar in crude protein (CP; 199 g/kg), neutral d...
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...
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...
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...
Köninger M, von Velsen-Zerweck A, Eiberger C, Jilg A, Töpper A, Visscher C, Reckels B, Vervuert I.Roughage alternatives for equine nutrition must be found due to the increasing climatic challenges. The aim of this study was to examine the nutrient composition and feed hygiene of alfalfa hay in comparison to meadow hay and to investigate the acceptance, weight development and faecal quality of broodmares fed alfalfa hay. The feed used was examined for nutrient content and hygiene status according to the standards of the Verband Deutscher Landwirtschaftlicher Untersuchungs- und Forschungsanstalten (VDLUFA). Twenty adult pregnant warmblood mares were fed in two groups (n=10) with a defined am...
Vervuert I, Voigt K, Hollands T, C÷¯ord D, Coenen M.Four horses were randomly fed a diet containing rolled, micronised or extruded barley; the barley intake was adjusted to supply 2 g starch/kg bodyweight per day. During a 10-day acclimatisation period the horses were also fed 1 kg grass hay/100 kg bodyweight per day. Samples of blood and breath were collected at the end of each period after the test meal of barley had been fed after a 12-hour overnight fast. The glycaemic and insulinaemic responses of the horses were measured as an indication of the pre-caecal digestibility of starch, and postprandial breath hydrogen and methane were measured ...
Thorringer NW, Jensen RB.Total collection of faeces is considered the golden standard for estimating apparent total tract digestibility (ATTD) in horses. However, the evaluation of individual feedstuffs is limited and determination of nutrient digestibility in different segments of the gastrointestinal tract (GIT) is excluded. The rationale for performing this study was that the mobile bag technique (MBT) can provide information on individual feedstuffs' degradation, and the use of fistulated animals does provide additionally information regarding degradation in individual segments of the GIT. Recommendations for usin...
Pulse RE, Baker JP, Potter GD.Three mature Thoroughbred geldings were used in duplicated trials conducted before and after cecal fistulation to determine the effects of the fistulation on nutrient digestion and indicator (Cr2O3 and polyethylene) retention time. There were significant increases (P<.01) in crude fiber and ether extract digestion following fistulation, while dry matter, gross energy, and crude protein digestibilities were not changed significantly. Retention times of Cr2O3 and polyethylene were increased significantly (P<-01 and P<.05, respectively) following fistulation. There were no significant differences...
Ragnarsson S, Lindberg JE.Eight mature Icelandic geldings were used in an experiment arranged as a change-over design to evaluate the effect of feeding level on the digestibility of a high-energy haylage-only diet. The horses were fed a low feeding level 10.7 g dry matter (DM)/kg body weight (BW) (maintenance) and a high feeding level 18.1 g DM/kg BW (1.5 × maintenance) during two 23 days experimental periods. Total collection of faeces was performed for 6 days at the end of each period to determine the coefficient of total tract apparent digestibility (CTTAD). The CTTAD for DM, organic matter, neutral detergent fibre...
