Nutrition in horses encompasses the study of dietary requirements and feeding practices that support equine health, growth, and performance. It involves the analysis of nutrients such as carbohydrates, proteins, fats, vitamins, and minerals, and their roles in equine physiology. Proper nutrition is essential for maintaining optimal body condition, supporting metabolic processes, and preventing dietary-related disorders. Research in this field examines the nutritional needs of horses at different life stages and activity levels, as well as the effects of various feed types and supplements. This page compiles peer-reviewed research studies and scholarly articles that explore the composition, digestion, and impact of different dietary components on equine health and performance.
Roberts MC, Kidder DE, Hill FW.Two enzymes having lactase activity are present in the equine small intestine. The first, the digestive enzyme, neutral beta-galactosidase, declines in activity from birth to three years, disappearing completely between 3 and 4 years of age. The other, the soluble lysosomal enzyme, acid beta-galactosidase, having affinity for lactose and a synthetic beta-galactoside, shows a decrease in activity in the first three months of life and thereafter varies little in activity and represents the lactase enzyme in the adult horse. This pattern may parallel the development of lactase activity in many ot...
Willoughby RA, MacDonald E, McSherry BJ, Brown G.Groups of young growing horses were fed toxic amounts of lead only, zinc only and the same amounts of lead and zinc together. Those fed Pb only developed pharyngeal and laryngeal paralysis ("roaring") whereas those fed Zn only and Pb and Zn together developed the same clinical syndrome which included swelling at the epiphyseal region of the long bones, stiffness and lameness. Anemia and decreased weight gains were most pronounced in animals fed Zn for the longest periods. Animals fed Pb only did not become anemic and weight loss did not occur until after there was an interference in swallowing...
Herrick JB.The importance of avoiding vitamin and mineral deficiencies and oversupplementation is discussed along with requirements for specific minerals and vitamins. Management implications of these requirements are presented.
Reitnour CM, Salsbury RL.Protein digestion, nitrogen retention, plasma protein, plasma urea, and plasma-free amino acids were determined for ponies fed 3 different protein supplements. Substitution of casein, corn gluten meal, or corn gluten meal plus lysine for a portion of the cornstarch in a low-protein basal ration increased apparent digestion of protein. Substitution with either casein or corn gluten meal plus lysine produced a significant increase (P less than 0.05) in nitrogen retention, whereas the corn gluten meal substitution did not. Nitrogen retention, expressed as percentage of nitrogen absorbed, was incr...
Kavazis AN, Sobota JS, Kivipelto J, Porter MB, Colahan PT, Ott EA.A diverse group of studies, which are equine exclusive, indicate that ribose administered to myocardial and skeletal muscle tissue stimulates ATP production and recovery. This study investigated the effects of ribose supplementation on blood and muscle metabolites and performance in Thoroughbred geldings performing a maximal treadmill standardised exercise test (SET). In Experiment 1, 6 conditioned Thoroughbred geldings performed a baseline SET and horses were assigned to one of 2 experimental treatment groups, placebo or ribose, based on VO2max. The placebo treatment group received 0.07 g glu...
Miller PA, Lawrence LM.Six mature Quarter Horse mares were used in a crossover design to assess the effect of dietary protein level on metabolic response to exercise. After a 2-wk adaptation period to either a 12.9% (control) or an 18.5% CP (high-protein) diet, each mare performed a standard exercise test. The test consisted of a 15-min exercise period at 4.5 m/sec on a 9% grade motorized treadmill. Exercise resulted in an increase in heart rate (P less than .001), but there was no difference (P less than .05) between dietary treatments. In the jugular vein, lactate increased (P less than .01) from 6.3 to 52.0 mg/10...
Winkelsett S, Vervuert I.Laminitis is a systemic disease which is manifested as a non infectious condition in the foot. The management of feeding and housing conditions is necessary to treat the endocrinological and metabolic disturbances of laminitic horses. The Equine Metabolic Syndrome (EMS) is predisposing for developing laminitis, and it is characterised by obesity, insulin resistance, hypertension and dyslipidaemia. A genetical predisposition is supposed and EMS is accompanied by a lack of exercise and inadequate energy intake. Laboratory examinations are of great importance for diagnosis. Analyses of insulin, g...
Lloyd JW, Rook JS, Braselton E, Shea ME.A study was designed to model the fluctuations of nine specific element concentrations in mammary secretions from periparturient mares over time. During the 1992 foaling season, serial samples of mammary secretions were collected from all 18 pregnant Arabian mares at the Michigan State University equine teaching and research center. Non-linear regression techniques were used to model the relationship between element concentration in mammary secretions and days from foaling (which connected two separate sigmoid curves with a spline function); indicator variables were included for mare and mare ...
Carmel DK, Crisman MV, Ley WB, Irby MH, Edwards GH.We surveyed the whole blood selenium status of a randomly sampled population of horses from 4 contiguous counties in northern Maryland. Two hundred and two horses from 74 farms were sampled. Whole blood selenium levels greater than or equal to 0.100 parts per million (ppm) were considered adequate; blood levels less than 0.100 ppm were considered marginal or deficient. The average blood selenium concentration of the horses sampled was 0.137 ppm, with a standard deviation of 0.041 ppm. Blood selenium concentrations ranged from 0.050-0.266 ppm. Thirty-eight of 202 horses (18.8%) had a selenium l...
Smyth GB, Young DW, Schumacher J.Postprandial gastrin concentrations were assayed in serum samples from a group of six foals at one day, one week, one month and three months of age. Before sampling, each foal was prevented from feeding for 2 h and was then allowed to suck for 15 mins. Blood samples were taken at the start of the meal and at 30 min intervals for the next 3 h. Feeding increased serum gastrin concentrations at one day, one week and one month, with the greatest increases detected at one day. Mean pre-feeding gastrin concentrations were 25.2 +/- 2.3 pg/ml at one day, 22.8 +/- 3.9 pg/ml at one week, 15.2 +/- 2.3 pg...
Nadal MR, Thompson DL, Kincaid LA.Two experiments were conducted to determine 1) the prolactin response to different kinds of feedstuffs in stallions and 2) the effects of total feed deprivation on prolactin secretion in mares and its interaction with the prolactin response to feeding. Experiment 1 was performed with stallions as a 6 x 6 Latin square: A) no feed; B) pelleted feed fed to meet 82.5% of the horses' CP requirements; C) pelleted feed at 25% of the amount in B; D) pelleted feed as in B plus water ad libitum; E) cracked corn at the weight in B; and F) chopped alfalfa at the weight in B. The positive prolactin respons...
Valiev AG, Valieva TA, Valeeva GR, Speranskiĭ VV, Levachev MM.The influence of essential fatty acids of mare's milk fat on the immunocompetent system and nonspecific resistance of male rats weighing 135-145 g was investigated after 6 weeks of feeding. Rats were fed with isocaloric purified diets containing 15% of test fat (in control--combination of lard and sunflower oil) which provide the ratio of omega-6/omega-3 fatty acids equal to 0.76. An increase of immune responsiveness and nonspecific resistance in the group fed with the diet with mare's milk fat on day 6 after a single immunization of the animals with 5% sheep erythrocyte suspension was noted.
DeBoer ML, Hathaway MR, Weber PSD, Sheaffer CC, Kuhle KJ, Martinson KL.Spring and late fall grazing can lead to metabolic problems in horses (Equus caballus L.) as a result of elevated nonstructural carbohydrates (NSC) in pastures. Therefore, the objectives were to determine the impact of different forage species on blood glucose and insulin concentrations of horses during the spring and late fall. Research was conducted in May (spring) and October (late fall) in St. Paul, MN. Alfalfa (Medicago sativa L.) and mixed perennial cool-season grasses (CSG) were grazed in spring, and CSG and teff (Eragrostis tef [Zucc.] Trotter) were grazed in late fall by six adult hor...
Handy LH, Peyton LC, Calderwood-Mays MB, Ackerman N.A diagnosis of gingival hyperplasia in a 22-year-old Quarter Horse gelding was confirmed by histologic examination. Clinical signs included difficulty eating hay, and a large, intraoral soft tissue mass measuring 13 x 8 x 4.5 cm. The mass was located in the mucosa on the lingual aspect of the caudal left portion of the mandible, ventral to the base of the tongue, and covered the second and third lower molars, extending rostrally along the buccal mucosa to the premolars. The left maxillary second and third molars were overgrown with sharp edges. Lateral radiography of the mandible revealed abse...
López López C, Celaya R, Santos AS, Rodrigues MA, Osoro K, Ferreira LM.Utilization of long-chain alcohols (LCOH) as diet composition markers in horses and cattle was assessed in a study conducted with 12 mature crossbreed mares (385±47 kg BW) and six adult non-lactating cows (499±36 kg BW) of Asturiana de los Valles breed. The LCOH data were combined with alkane and long-chain fatty acid (LCFA) data to test the applicability of combining these markers to estimate diet composition. Animals were randomly divided into groups of three animals and received a daily total amount of 1.0 kg dry matter/100 kg BW of diets composed of different proportions of ryegrass (Lol...
Lochner HL, Hutchinson ML, Wilson ML, Bianco AW, Johnston LJ, Prigge JL, Martinson KL.Recent changes in rendering availability for chemically-euthanized animals have created a need to explore composting as an equine mortality management method. The objectives of this study were to evaluate equine mortality composting in the Upper Midwest during fall and spring, document sodium pentobarbital concentrations throughout the process, and determine nutrient content of finished compost. During each season, four horses were euthanized by intravenous administration of sodium pentobarbital. Carcasses were positioned at the center of a woodchip and shavings base and covered with a 2:1 mix...
Houpt KA, Perry PJ, Hintz HF, Houpt TR.Twelve ponies were fed their total daily ration either as one large meal or divided into six small meals. Pre- and post-feeding behavior was recorded six times a day. Blood samples were taken for 30 min before and two hr after the meal. Plasma protein increased from 7.0 to a peak of 7.3 g/dl with small meals and from 7.3 to 8.1 g/dl with large meals, and returned to pre-feeding levels by 90 min post-feeding. Hematocrit rose from 33.3 to 34.1% with small meals and from 33.0 to 36.0% with large meals. These rapid and short-lived increases indicate a decrease in plasma volume. Plasma osmolality r...
Ebert M, Moore-Colyer MJS.The aim of this study was to estimate the energy requirements of Thoroughbred racehorses in active training for flat racing. Twenty-two Thoroughbred racehorses in England were measured over periods from 6 to 15 wk, which included periods of active race training and temporarily reduced training. Energy intake was determined by measuring daily feed consumption. Energy output was measured using heart rate monitors during 730 training sessions, relating heart rate (HR) to oxygen consumption (VO2) and converting VO2 to energy. Field maintenance requirements were calculated by deducting the marginal...
Emmerich IU.In 2020, one novel pharmaceutical agent for horses or food-producing animals was released on the German market, rendering the inhaled glucocorticoid ciclesonide (Aservo EquiHaler) available for horses for the first time. The authorization of one established veterinary active ingredient was extended to an additional species: The anthelmintic fenbendazole (Gallifen) from the benzimidazole group is now also authorized for pheasants. Additionally, 3 veterinary drugs with a new combination of active ingredients (ketoprofen + tilmicosin, ketoprofen + tulathromycin, prednisolone + lidoc...
Jackson K, Kelty E, Tennant M.Equine peripheral caries can cause significant morbidity and can have considerable welfare implications. Recent research suggests that diets with high water soluble carbohydrate (WSC) content are associated with high risk of peripheral caries. Previous work has indicated that the condition may be treatable if the inciting cause is removed and the damaged tooth allowed to erupt out, being replaced by the unaffected tooth previously under the gingival margin. Objective: To see whether the peripheral caries process can be ceased if oaten hay (typically high WSC) is removed from the diet and repla...
Lawrence L.The National Research Council (NRC) published the Recommended Nutrient Allowances for Horses in 1949. The subsequent publication was renamed the Nutrient Requirements of Horses and the 6th revised edition was published in 2007. The document has increased in size and scope from the initial publication in 1949 that contained 29 pages to the most recent version with 341 pages. Several formats for expressing requirements (dietary concentrations or daily amounts) have been utilized. In addition, a variety of methods have been employed to determine the nutrient requirements of horses since 1949. Man...
Morris DD, Henry MM, Moore JN, Fischer K.In laboratory animals, the incorporation of alpha linolenic acid or other n-3 series fatty acids into the diet results in marked changes in cell membrane composition as well as arachidonic acid metabolism. The purpose of the present study was to determine whether endotoxin-induced thromboxane A2 (TxA2) and/or prostacyclin (PGI2) production by equine peritoneal macrophages was altered by feeding horses a diet containing 8% linseed oil as a source of alpha linolenic acid for 8 weeks. Peritoneal macrophages were cultured in vitro in the presence of endotoxin (LPS) (0.5-500 ng/ml) or calcium ionop...
Valieva TA, Valiev AG, Kulakova SN, Levachev MM.During six weeks rats were given a ration containing, as the only source of fat, lipids of sublimated mare's milk that had been stored with or without antioxidants (quercitrol, bisalcophen) during 3 months. The influence of specific quality of the ration fat on lipids and fatty acid composition of lipids in blood plasma, erythrocytic stroma and liver tissue, as well as on lipid peroxidation in the tissues was studied in the test animals. No changes induced by the lipids from sublimated mare's milk were detected in the parameters studied.
Hanc A, Boucek J, Svehla P, Dreslova M, Tlustos P.The aim of this work was to determine the influence of aeration and time of extraction on the agrochemical properties of aqueous extracts from vermicomposts made from horse manure (M) and apple pomace (P) waste. There were two extract treatments: stirring without aeration (S), and stirring with aeration (A) for 48 h. Aeration significantly increased the levels of electrical conductivity (EC) and the concentration of [Formula: see text], [Formula: see text], and macro-elements in the extracts. In the (A) treatment, the extraction efficiency of K and Mg increased twofold, and the extraction ef...
Meyer H.Animal nutrition is not a main subject in veterinary medicine training, nevertheless it has been taught in the Tierärztliche Hochschule Hannover since its foundation in 1778. In the very beginning only a few lectures about feedstuffs and toxic plants for horses and feeding technique have been presented. During the 19th century animal nutrition was taught about 20 h under the general topic: Gesundheitspflege or Dlätetik. Diätetik included in that time all factors which are important for health as soil, water, climate, stable, hamess and nutrition, too. Textbooks about "Gesundheitspflege" fro...
MacQuarrie J.A 2-day-old Quarter Horse colt was presented to the Atlantic Veterinary College for recumbency and diarrhea. Dietary history of the dam, serum biochemistry findings, and whole blood selenium levels were consistent with nutritional myodegeneration. The patient was treated successfully with fluid therapy and broad-spectrum antimicrobials. Recovery was uneventful, and the patient was discharged with a favorable prognosis. Un poulain Quarter Horse âgé de deux jours a été présenté à l’Atlantic Veterinary College pour un décubitus et de la diarrhée. L’anamnèse nutritionnelle de la mè...
Finno CJ, McKenzie E, Valberg SJ, Pagan J.Recurrent exertional rhabdomyolysis (RER) occurs in fit, nervous Thoroughbreds fed high nonstructural carbohydrate (NSC) diets. Clinical signs are diminished by feeding low NSC, high fat diets; however, the mechanism is unclear. Objective: To determine if the glucose, insulin and cortisol response to isocaloric diets varying in fat and NSC availability differ in fit vs. unfit Thoroughbreds with RER. Methods: Four fit (10 weeks treadmill training) RER Thoroughbred mares were exercised and fed 3 isocaloric (121 MJ/day) diets in a 5 day/diet block design. Two high NSC concentrates, sweet feed (SF...
Mirahmadi F, Koolstra JH, Fazaeli S, Lobbezoo F, van Lenthe GH, Snabel J, Stoop R, Everts V.Nutrition of articular cartilage relies mainly on diffusion and convection of solutes through the interstitial fluid due to the lack of blood vessels. The diffusion is controlled by two factors: steric hindrance and electrostatic interactions between the solutes and the matrix components. Aging comes with changes in the cartilage structure and composition, which can influence the diffusion. In this study, we treated fibrocartilage of mandibular condyle with ribose to induce an aging-like effect by accumulating collagen crosslinks. The effect of steric hindrance or electrostatic forces on the d...
Mack JK, Remler HP, Senckenberg E, Kienzle E.The objective of this study was to investigate the effects of a different energy supply on the development of Warmblood foals with a focus on examining the recommended allowances of the German Society for Nutrition Physiology. Methods: Two groups of foals received different amounts of concentrates from the 1st until the 6th month of life. With regards to the total energy content, the rations were composed to either comply with the recommendations (6) (group "Norm", n=15) or to exceed those by approximately 20% (group "Zulage", n=16). The supply with concentrates of the group "Norm" aimed for a...
Abaturov BD, Dmitriev IA, Jargalsaikhan L, Omarov KZ.The amount of phytomass removed by a complex of livestock (horses, cattle, sheep, and goats) and wild ungulates (Mongolian gazelle Procapra gutturosa Pall.) grazing in plain and mountain pastures of eastern Mongolia has been estimated by taking account of feces deposited by these animals. The results show that at an animal density of up to 30 head/km2, the total annual amount of feces reaches 140 kg/ha (dry weight), with the greater part (up to 90 kg/ha) being deposited by horses. The contribution of Mongolian gazelles in some pastures reaches 20-40 kg/ha per year. Decomposition of feces proce...
Hallebeek JM, Beynen AC.The hypothesis was tested that feeding ponies a diet containing medium-chain triacylglcyerols (MCT) instead of soya bean oil causes an increase in the production of plasma triacylglycerols, which, under steady-state conditions, is associated with an increased clearance of triacylglycerols. Six ponies were fed rations containing either MCT or an isoenergetic amount of soya bean oil according to a cross-over design. The concentration of MCT in the total dietary dry matter was about 13%. When the ponies were fed the diets for 3 weeks, plasma triacylglycerol concentrations were 0.42 +/- 0.09 and 0...
Warren LK, Whelen A.The gruelling race schedules maintained by horses competing in chuckwagon racing raises concern for the horses' ability to recover quickly and continue to perform at a high level. The amount of bodyweight lost and the time required for recovery of this weight loss have been used to assess the level of stress imposed on horses competing in various multiple-day events. In this study, bodyweights were obtained from 40 Thoroughbred geldings (mean +/- s.e.; bodyweight 521.5 +/- 4.4 kg) before and after racing during a 5 day chuckwagon race meet. Body condition score (BCS) was determined on the firs...
Tisserand JL, Ottin Pecchio M, Rollin G.The cellulolytic activity in the large intestine of the pony varies according to the form and the composition of the feed. This activity was measured on two caecal and ventral colon-cannulated ponies receiving the following 4 diets during four successive 6-week periods: --6 kg of hay, --4 kg of hay + 1 kg of oats, --6 kg of ground, pelleted hay. --5 kg of a ground, pelleted blend of 80 p. 100 hay and 20 p. 100 oats. Adding oats to a hay feed increased the cellulolytical activity in the caecum and the colon, whereas grinding and pelleting hay alone or hay enriched with oats diminished that acti...