Forage is a primary component of the equine diet, consisting mainly of grasses, hay, and legumes that provide essential nutrients and fiber. It plays a significant role in maintaining digestive health and supporting the overall well-being of horses. The nutritional composition of forage can vary based on factors such as plant species, maturity at harvest, and environmental conditions. Proper management and selection of forage are important for meeting the dietary needs of horses and preventing issues such as colic or laminitis. This page compiles peer-reviewed research studies and scholarly articles that explore the nutritional value, management practices, and impact of forage on equine health and performance.
Hart R, Bailey A, Farmer J, Duberstein K.Mastication is the initial phase of digestion and is crucial to equine health due to its role in saliva production and food particle reduction. Hay nets have been promoted to slow the rate of hay consumption, with many styles of slow feeders available. Limited research has shown that nets may slow consumption, but no research has examined their effect on the horse's chewing frequency and patterns. The objective of this study was to compare chew frequency (CF, total number of chews/kg consumed) and chew duration (CD, total minutes chewed/kg consumed), as well as distribution of chews over a fee...
Gartland B, Strunk W, Schulte B, DeGraves F, Koostra J.Horses can become obese and develop related health issues such as laminitis from excessive grazing on high-quality pasture grass; limiting pasture intake can allow weight loss to occur. The objective of this study was to determine the effect of space-restricted rotational grazing on body weight (BW) and time budgets in horses. Eight mature geldings and mares with maintenance-only requirements were randomly assigned to either a space-restricted rotational grazing group (SRG; BW 512 ± 6 kg; n = 4) or a continuous grazing group (CG; BW 517 ± 49 kg; n = 4) for 42 d SRG horses grazed an area with...
Silva AH, Lucena JEC, Taran FMP, Cunha DS, Almeida JAT, Lima RS, Dias WS, Santiago JM.This study aimed to compare the digestibility of tropical grasses by horses by the in vivo method using mobile nylon bags with the in vitro digestibility method using horse feces as a source of inoculum. Five horses were used in a 2 × 5 factorial design with randomized blocks featuring two methods (in vivo and in vitro) and five grasses: Tifton 85 hay (Cynodon spp.), sixweeks threeawn grass (Aristida adsencionis, Linn), Alexandergrass (Brachiaria plantaginea (Link) Hitchc.), capim-de-raiz (Chloris orthonoton, Doell), and Sabi grass (Urochloa mosambicensis). No difference (P>0.05) was foun...
Bordin C, Raspa F, Greppi M, Harris P, Ellis AD, Roggero A, Palestrini C, Cavallini D, Bergero D, Valle E.In the last decade, haynets and slow feeders have been promoted as sustainable tools to improve the feeding management of horses and reduce forage waste, but little is known about their effects on ponies. Therefore, the aim of this study was to analyze the effects of different hay feeding methods on the ingestive behaviors, intake rate and mouth shaping of ponies belonging to two breed types, which are characterized by different head morphologies. Shetland type (SH, n = 5) and Welsh/Cob type (WC, n = 4) ponies were fed hay using four feeding methods: on the ground (G), a fully filled h...
Köninger M, von Velsen-Zerweck A, Eiberger C, Löffler C, Töpper A, Visscher C, Reckels B, Vervuert I.The aim of this study was to examine the nutrient composition and feed hygiene of alfalfa as well as investigate the feed intake, blood, urine and faecal parameters of horses fed alfalfa haylage (AS) compared with alfalfa hay (AH) and meadow hay (MH). A total of 11 geldings were fed ad libitum (2.1% dry matter (DM) of body weight (BW)) with alfalfa haylage, alfalfa hay and meadow hay (MH) in a Latin square design. On days 0 and 21 of the feeding period, blood samples were analysed for kidney and liver parameters. Faecal samples were analysed for pH, DM and short-chain fatty acids (SCFAs). Spon...
Stowe CJ, White H.An overabundance of wild horses and burros on federal lands can lead to suboptimal welfare when there are insufficient forage and water resources. Placing some of these animals in private homes has been identified as a key part of the solution. A nationwide online survey completed by 2,247 current and former horse owners is used to assess the feasibility of accommodating this strategy. The survey tool addressed basic horse ownership and demographic information, previous experience with wild horses, and hypothetical wild horse adoption scenarios. Results suggest that most respondents are recept...
Diez de Castro E, Fernandez-Molina JM.Environmental practices related to the inhalation of airborne dust have been identified as the main cause of equine asthma (EA) and reasonably, they are truly relevant in its treatment and control, especially for horses with its severe form. Vast research regarding environmental recommendations has been conducted in recent years. However, no recent exhaustive reviews exist that gather all this new evidence. The aim of this review is to report and compare the most pertinent information concerning the environmental management of EA. The main findings highlight the importance of the type of forag...
Macon EL, Harris P, McClendon M, Perron B, Adams A.Hyperinsulinemia-associated laminitis (HAL) is the primary concern for insulin dysregulated (ID) equids and their insulin response to the consumption of oral, nonstructural carbohydrates (NSC) has been shown to be a risk predictor for HAL development. This randomized, crossover study's objective was to examine the insulinemic responses to 3 forage pellets (1 g/kg BW) (timothy hay, TH, 9.5 % CP & 10 % NSC DM; alfalfa hay, AH, 16.3 % CP & 9.8 % NSC DM; timothy-alfalfa hay; TAH, 17.2 % CP & 9.8 % NSC DM) along with a positive (dehulled oats; OG, 14.7 % CP & 59.7 % NSC DM) and negative dietary cha...
Abbas G, Ghafar A, McConnell E, Beasley A, Bauquier J, Wilkes EJA, El-Hage C, Carrigan P, Cudmore L, Hurley J, Gauci CG, Beveridge I, Ling E....This study quantified the extent of anthelmintic resistance (AR) in ascarid and strongylid nematodes against commonly used anthelmintics in Australian Thoroughbred horses. Faecal egg count reduction tests (FECRTs, n = 86) and egg reappearance period (ERP) tests were conducted on 22 farms across Australia. Faecal egg counts (FECs) were determined using the modified McMaster technique, and percent faecal egg count reduction (%FECR) was calculated using the Bayesian hierarchical model and hybrid Frequentist/Bayesian analysis method. The results were interpreted using old (published in 1992) and...
Son V, Penagos-Tabares F, Hollmann M, Khiaosa-Ard R, Sulyok M, Krska R, Zebeli Q.Pastures are used for grazing and the production of conserved roughage in horses. Yet, the nutritional profile of the forage varies from spring to late summer, affecting equine nutrient supply and health. In addition, environmental factors may also favor plant contaminants such as mycotoxins. This study aimed to determine the nutritional profile and contaminant load of selected horse pastures from early spring till late summer. The nutrient composition (main macronutrients, macro elements and trace elements), as well as mycotoxins, metabolites, pesticides, and plant-derived compounds of seven ...
Ugulu I, Khan ZI, Ahmad K, Bashir H, Mehmood N, Zafar A.The present study aimed to determine the accumulation levels of arsenic in pasture soil, forage and animals. An atomic absorption spectrophotometer was used to determine the concentration of metals in the samples of soil, forage and blood plasma of horses. The level of arsenic ranged between 4.26 mg/kg (summer) and 4.66 mg/kg (winter) in soil samples and 2.67 mg/kg (summer) and 2.94 mg/kg (winter) in forage samples. In blood plasma samples, the mean arsenic (As) values varied between 1.38 and 1.52 mg/L. In the blood plasma samples, the mean As values varied between 1.38 and 1.52 mg/L. No...
Ward AB, Harris PA, Argo CM, Watson CA, Burns NM, Neacsu M, Russell WR, Grove-White D, Morrison PK.Native ponies are at increased risk of obesity and metabolic perturbations, such as insulin dysregulation (ID), a key risk factor for endocrinopathic laminitis. Management and feeding practices can be adapted to maintain healthy body condition and support metabolic health, but owners may inadvertently provide their ponies with inappropriate management leading to obesity and exacerbating risk of metabolic disease. Adoption of preventative weight management approaches (WMAs), including regular monitoring of body condition, providing appropriate preserved forage, promoting seasonal weight loss, a...
Hain AM, Þórisdóttir SL, Tretow M, Bienert-Zeit A.In the context of a study of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH), elderly Icelandic horses were examined in their originating country. The subject of this survey was the impact of dental treatment and keeping and feeding management on the health of the rostral oral cavity. A total of 170 horses (aged ≥ 15) located in different areas of Northwest, West, and South Iceland. The horse owners completed a questionnaire about keeping, feeding, and preventative dental care. The horses were clinically examined with particular attention to gingival and dental disorders of...
Carvalho Seabra J, Hess T, Martinez do Vale M, Spercoski KM, Brooks R, Dittrich JR.Free choice forage could be the best option regarding horses' welfare but can lead to increased body weight (BW), and waste of hay. Automatic box feeders (BF) and slow feeders (SF) decrease food waste, but it is unknown how these affect the horses' time-budget (TB). This study compared the effects of feeding free choice hay (FC), to a SF and an automated BF on the horses' cortisol circadian rhythm (CCR) and behavior by 24-hours continuous behavioral sampling (CBS). The study was designed as a 3 × 3 Latin square design with 15 polo horses divided into 3 groups, for 15 days on each treatment....
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...
Zicarelli F, Tudisco R, Lotito D, Musco N, Iommelli P, Ferrara M, Calabrò S, Infascelli F, Lombardi P.Determination of digestibility represents the first step for the evaluation of the net energy content of feed for livestock animals. The aim of this study was to evaluate the in vivo digestibility and in vitro degradability of five diets characterized by different forage/concentrate ratios (F:C) in horses. The in vitro degradability was determined by the Gas Production Technique (GPT), using as an inoculum source the feces of the same subjects used for the in vivo test. Five diets consisting of poliphyte hay, straw and grains of barley and oats with a different F:C ratio [90/10 (Diet 1); 78/22...
Bordin C, Raspa F, Harris P, Ellis AD, Roggero A, Palestrini C, Bergero D, Valle E.The application of hay feeding devices, such as the use of hay nets or slow feeders, can help with the management of weight in ponies; however, there is still a lack of knowledge regarding their effect on equine posture. Therefore, the aim of the study was to assess the effect of different feeding devices on the posture of ponies using morphometric analysis. Two different breed types, Shetland type (SH, n = 5) versus Welsh Cob type (WC, n = 4), were fed the same forage in four different ways: on the ground (G), using a fully filled haynet (HF), using a partially filled haynet (HL) and...
Karasu GK, Rogers CW, Gee EK.Sustainability is the balancing act of optimizing the use of current resources without compromising the current or future environment. Within the agriculture sector the primary focus of sustainability has been to reduce environmental pollution, specifically greenhouse gasses (GHG) emissions, nitrogen emissions, and leaching. For the equine industry the first step towards sustainability is the documentation and critique of current feeding and management practices to permit modifications to enable the industry meet social and legislative obligations. As a monogastric hindgut fermenter on a per k...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from the seeds of Houtt. (nutmeg oil), when used as a sensory additive in feed and water for drinking for all animal species. The additive contains myristicin (up to 12%), safrole (2.30%), elemicin (0.40%) and methyleugenol (0.33%). For long-living and reproductive animals, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) considered of low concern the use of the additive in complete feed at 0.2 mg/kg for laying hens and...
Hyde KA, Altman A, Banasek R, Gastal MO, Gastal EL.Hay wastage when feeding round bales due to contamination, deterioration, and animal refusal can accrue large financial losses for farmers. The present study investigated the efficiency of the conventional Tombstone-style feeder system compared to the Hay Saver feeder system to reduce hay wastage in feeding round hay bales. Mares were distributed equally into two groups, Tombstone and Hay Saver, and fed six bales per group over 48 days. Hay wastage was collected daily, dried, and weighed, while the mares were weighed weekly. Overall, the Hay Saver feeder showed less hay wastage, higher mean ma...
Julliand S, Buttet M, Hermange T, Hillon P, Julliand V.Nutritional factors are suggested to influence the incidence and severity of glandular gastric disease (GGD) in horses. Objective: To retrospectively assess whether dietary fermentable carbohydrates increase the severity of GGD and to prospectively evaluate whether the partial substitution of concentrates by dehydrated alfalfa would decrease GGD severity scores. Methods: In total, 82 trotters from 4 training centers exercised ≥5 days/week. Methods: Multicenter retrospective observational study, and prospective 2-arm randomized trial. Glandular mucosae were observed by gastroscopy and score...
Ermers C, McGilchrist N, Fenner K, Wilson B, McGreevy P.Failure to meet the minimum forage requirement of 1.5% of the horse's bodyweight and the opportunity for foraging for a minimum of 8 h a day (not going without this opportunity longer than four to five consecutive hours) can have both physiological and behavioural consequences. To provide an energy source for horses, rations often include starch rather than fibre. This can result in health issues related to the gastrointestinal tract (GIT) in the horse. In the stomach, the main concern is equine gastric ulcer syndrome (EGUS) and, more specifically, equine squamous gastric disease (ESGD). Ulcer...
Moore-Colyer M, Westacott A, Rousson L, Harris P, Daniels S.Despite our improved understanding of equid digestive health and accurate rations formulations, obesity in the UK horse population remains high. Study aims: (1) to determine how owners are feeding their horses and what influences their choices, (2) to understand owners' knowledge of haylage and (3) to identify key areas that require additional education. Data were collected in 2020 from 1338 UK horse owners via two online surveys. Survey 1 was on general feeding practices, and Survey 2 was specifically on the feeding of haylage. Data were processed using chi square analyses + Bonferroni tests,...
Clauss M, Codron D, Hummel J.Like other members of the odd-toed ungulates (the perissodactyls), equids once had a higher species diversity in the fossil record than they have today. This is generally explained in comparison to the enormous diversity of bovid ruminants. Theories on putative competitive disadvantages of equids include the use of a single toe as opposed to two toes per leg, the lack of a specific brain cooling (and hence water-saving) mechanism, longer gestation periods that delay reproductive output, and in particular digestive physiology. To date, there is no empirical support for the theory that equids fa...
Petz V, Khiaosa-Ard R, Iben C, Zebeli Q.Chewing is an essential physiological process in horses; yet, the physical form of feeds may affect their chewing and feeding behaviour with consequences for equine digestion and health. The present study evaluated the potential of a commercial forage cubes made from alfalfa and mixed meadow grasses to maintain chewing activity when compared with a traditional long and fibre-rich hay. An additional aim was to measure the dust formation during feeding. The experiment was a crossover design with six horses (11 ± 4 years old, mean ± SD), fed with 5 kg (as-fed basis) of their feed (long hay...
Weinert-Nelson JR, Biddle AS, Sampath H, Williams CA.Integrating warm-season grasses into cool-season equine grazing systems can increase pasture availability during summer months. The objective of this study was to evaluate effects of this management strategy on the fecal microbiome and relationships between fecal microbiota, forage nutrients, and metabolic responses of grazing horses. Fecal samples were collected from 8 mares after grazing cool-season pasture in spring, warm-season pasture in summer, and cool-season pasture in fall as well as after adaptation to standardized hay diets prior to spring grazing and at the end of the grazing seaso...
Ögren G, Ragnarsson S, Jansson A.Knowledge of endogenous nutrient losses is important when estimating the nutrient requirements of animals. It has been suggested that faecal endogenous phosphorus (P) losses differ between growing and adult horses, but studies on foals are scarce. In addition, studies on foals on forage-only diets with different P contents are lacking. Thus this study: (1) assessed faecal endogenous P losses in foals fed a grass haylage-only diet close to or below estimated P requirements; (2) evaluated use of serum cross-linked carboxyterminal telopeptides of type-I collagen (CTx) as a marker of bone resorpti...
Thomassen EE, Sigsgaard EE, Jensen MR, Olsen K, Hansen MDD, Svenning JC, Thomsen PF.Trophic rewilding is increasingly applied in restoration efforts, with the aim of reintroducing the ecological functions provided by large-bodied mammals and thereby promote self-regulating, biodiverse ecosystems. However, empirical evidence for the effects of megafauna introductions on the abundance and richness of other organisms such as plants and invertebrates, and the mechanisms involved still need strengthening. In this study, we use environmental DNA (eDNA) metabarcoding of dung from co-existing feral cattle and horses to assess the seasonal variation in plant diet and dung-associated a...
Muhonen S, Julliand V.Racing events challenge the fluid balance of athletic horses. The equine large intestine functions as a fluid reservoir, since the properties of dietary forage fibre affect the digesta water content and the milieu of this ecosystem. This study aimed to investigate the effect of grass maturity and legume forage on the faecal water-holding capacity (WHC) and microbial ecosystem, and the fluid balance and body weight (BW) of French trotters in race training. Six geldings were offered three diets with different fibre compositions: concentrate and late-harvested mature grass haylage (35:65 energy r...
Leise JM, Leatherwood JL, Paris BL, Walter KW, George JM, Martinez RE, Glass KP, Lo CP, Mays TP, Wickersham TA.Thirty stock type geldings (15 ± 3 years; 556 ± 63 kg BW) were used in a randomized complete design over 28 days to determine the influence of cannabidiol (CBD) oil supplementation levels on body weight, body condition, and blood chemistry. Horses were randomly assigned to one of three dietary treatments (n = 10 per treatment) formulated with canola oil to provide 1.50 mg CBD/kg BW (TRTA), 0.75 mg CBD/kg BW (TRTB), or 0.00 mg CBD/kg BW (canola oil; CTRL). Treatments were top-dressed onto concentrate and individually administered twice daily. Horses were maintained in adjacent dry lots and re...
Cymbaluk NF, Christison GI.Horses are reared in all types of weather. Temperatures as diverse as -40 degrees C to 40 degrees C are tolerated by horses. The nutrient requirement most influenced by cold weather is energy. In cold weather, feeding good quality hays free-choice is usually sufficient for mature horses in good body condition. Grain may have to be fed when poor quality hays are used. Hot weather (greater than 30 degrees C) necessitates heat loss to maintain body core temperature. Horses sweat to reduce body heat. Heat stress can be minimized by feeding diets that reduce the heat increment. Use of grain and fat...
Muhonen S, Julliand V, Lindberg JE, Bertilsson J, Jansson A.The objective of this study was to investigate the effect of an abrupt change from grass hay (81% DM) to grass silage (36% DM) or grass haylage (55% DM), fed at similar DM intakes, and to compare the effects of silage and haylage on the composition and activities of the colon microflora. The forages were from the same swath harvested on the same day. Four adult colon-fistulated geldings were randomly assigned to diets in a crossover design. The study started with a preperiod when all 4 horses received the hay diet, followed by an abrupt feed change to the haylage diet for 2 horses and the sila...
Zhu Y, Wang X, Deng L, Chen S, Zhu C, Li J.Diet is an important factor affecting intestinal microbiota in horses. Fecal microbiota is commonly used as a substitute for studying hindgut microbiota when investigating the relationship between intestinal microbial changes and host health. So far, no study has compared the difference between the fecal microbiota found in horses that are fed pasture grass, silage, and hay. The present study aims to characterize the fecal microbiota in horses that were exclusively on one of the three forage diets, and to analyze the potential impact of these forages, especially silage, on horse intestinal hea...
Weinert-Nelson JR, Biddle AS, Williams CA.Diet is a key driver of equine hindgut microbial community structure and composition. The aim of this study was to characterize shifts in the fecal microbiota of grazing horses during transitions between forage types within integrated warm- (WSG) and cool-season grass (CSG) rotational grazing systems (IRS). Eight mares were randomly assigned to two IRS containing mixed cool-season grass and one of two warm-season grasses: bermudagrass [Cynodon dactylon (L.) Pers.] or crabgrass [Digitaria sanguinalis (L.) Scop.]. Fecal samples were collected during transitions from CSG to WSG pasture sections (...
Moore BE, Dehority BA.The effects of diet and hindgut defaunation (removal of protozoa from the hindgut) on diet digestibility (Trial 1) and on total and cellulolytic bacterial and fungal concentrations in the cecum and colon (Trial 2) were investigated. A high-forage (HF) diet, 90% alfalfa hay-10% concentrate, or a higher-concentrate (HC) diet, 60% alfalfa hay-40% concentrate, was limit-fed. In Trial 1, defaunation resulted in a slight decrease in DM digestibility (P < .1) and had no effect on cellulose digestibility. Dry matter digestibility was higher (P < .001) with the HC diet; however, no differences were obs...
Pearson RA, Merritt JB.Four donkeys and four ponies maintained in climate rooms, were provided with meadow hay or barley straw supplemented with minerals and vitamins ad libitum. Both diets were given to all animals for periods of 21 days. Measurements were made during the last seven days following single doses of two non-absorbable markers (Cr-fibre and Co-EDTA). After six weeks the donkeys repeated the trial, walking 14 km and ascending 260 m five days per week. At rest ponies ate more than donkeys, however the donkeys showed a higher digestibility of dry matter (DM), organic matter (OM) and acid detergent fibre (...
Rapson JL, Schott HC, Nielsen BD, McCutcheon LJ, Harris PA, Geor RJ.Age and diet may affect insulin sensitivity (SI) but these factors have received limited investigation in horses. Objective: To measure minimal model parameters during an insulin-modified frequently sampled intravenous glucose tolerance test (FSIGTT) after adaptation to a forage only diet (HAY) or forage supplemented with either starch/sugar-rich (SS) or oil/fibre-rich (FF) concentrate feeds; and to assess glucose and insulin responses to a standardised meal challenge (SMC, 4 g/kg BW of SS) after diet adaptation in adult and aged mares. Methods: Latin square design with eight adult (5-12 yea...
Lane HE, Burns TA, Hegedus OC, Watts MR, Weber PS, Woltman KA, Geor RJ, McCutcheon LJ, Eades SC, Mathes LE, Belknap JK.Insulin dysregulation, obesity, and exposure to high-nonstructural carbohydrate (NSC) forage are risk factors for equine metabolic syndrome-associated laminitis (EMSAL); high systemic insulin concentrations in EMSAL are proposed to induce cellular dysregulation in the digital lamellae through activation of the insulin-like growth factor-1 receptor. Objective: To use a dietary challenge model (DCM) and a euglycaemic-hyperinsulinaemic clamp (EHC) model to assess lamellar growth factor-related signalling. Methods: Lamellar phospho (P)-protein concentrations of signalling proteins important in gro...
Elia JB, Erb HN, Houpt KA.The natural diet of free-ranging horses is grass, which is typically high in fiber and calorically dilute, however diets for high performance domestic horses are often low in fiber and calorically dense. The aim of the study was to determine the motivation of horses for hay when fed a low roughage diet. Their motivation could be used to determine if low roughage diets compromise the welfare of horses. Eight mares were fed two different diets in counterbalanced order: ad libitum orchard grass hay; a complete pelleted feed (pellets). Each trial lasted three weeks, with a one-week transition peri...
Murray MJ, Schusser GF.A glass combined pH-reference electrode was placed in the stomachs of 5 adult horses and pH was recorded every 6 mins for 24 h while (1) feed and all bedding materials were withheld for 24 h (unfed), (2) horses had free access to Timothy grass hay for 24 h (fed), and (3) horses had free access to Timothy grass hay and were treated with ranitidine, 6.6 mg/kg body weight, orally, every 8 h for 48 h (fed + ranitidine). There was a significant (P = 0.007) difference in median 24-h gastric pH amongst the 3 protocols, the value being 3.1 in fed horses and 1.55 in unfed horses (P = 0.05) and 4.6 in f...
Olave CJ, Ivester KM, Couetil LL, Kritchevsky JE, Tinkler SH, Mukhopadhyay A.Respirable dust exposure is linked to airway inflammation in racehorses. Feeding haylage may reduce dust exposure by 60-70%. The objective of this study was to compare dust exposure, airway cytology, and inflammatory cytokine concentrations between horses fed haylage or hay over 6 weeks while in training. Seven healthy Standardbred horses were randomly assigned to be fed alfalfa hay (n = 3) or grass-alfalfa mix haylage (n = 4) for six weeks while training on a treadmill. Dust exposure was measured gravimetrically at the breathing zone. Endotoxin and β-glucan concentrations in respirable dust ...
Husted L, Sanchez LC, Olsen SN, Baptiste KE, Merritt AM.Stall housing has been suggested as a risk factor for ulcer development in the equine stomach; however, the exact pathogenesis for this has not been established. Objective: To investigate the effect of 3 environmental situations (grass paddock, stall alone or stall with adjacent companion) on pH in the proximal and the ventral stomach. Methods: Six horses with permanently implanted gastric cannulae were used in a randomised, cross-over, block design. Each horse rotated through each of three 24 h environmental situations. Horses remained on their normal diet (grass hay ad libitum and grain b.i....
Ragnarsson S, Jansson A.The aim of the present study was to compare digestibility and metabolic response in Icelandic and Standardbred horses fed two grass haylages harvested at different stages of maturity. Six horses of each breed were used in a 24-day change-over design. A total collection of faeces was made on days 15-17 and 22-24. Blood samples were collected on day 24 of each period and analysed for total plasma protein (TPP), plasma urea, non-esterified fatty acids, cortisol and insulin concentration. There were no differences in digestibility coefficients of crude protein, neutral detergent fibre or energy be...
Krueger K, Esch L, Farmer K, Marr I.Every animal species has particular environmental requirements that are essential for its welfare, and when these so-called "basic needs" are not fulfilled, the animals suffer. The basic needs of horses have been claimed to be social contact, social companionship, free movement and access to roughage. To assess whether horses suffer when one or more of the four proposed basic needs are restricted, we examined several studies ( = 38) that reported behavioural and physiological reactions to these restrictions. We assigned the studies according to the four types of responses investigated: (a) Str...
Nedjadi T, Moran AW, Al-Rammahi MA, Shirazi-Beechey SP.The diet of the horse, pasture forage (grass), is fermented by the equine colonic microbiota to short-chain fatty acids, notably acetate, propionate and butyrate. Short-chain fatty acids provide a major source of energy for the horse and contribute to many vital physiological processes. We aimed to determine both the mechanism of butyrate uptake across the luminal membrane of equine colon and the nature of the protein involved. To this end, we isolated equine colonic luminal membrane vesicles. The abundance and activity of cysteine-sensitive alkaline phosphatase and villin, intestinal luminal ...
Franz R, Soliva CR, Kreuzer M, Hummel J, Clauss M.It is assumed that small herbivores produce negligible amounts of methane, but it is unclear whether this is a physiological peculiarity or simply a scaling effect. A respiratory chamber experiment was conducted with six rabbits (Oryctolagus cuniculus, 1.57±0.31 kg body mass) and six guinea pigs (Cavia porcellus, 0.79±0.07 kg) offered grass hay ad libitum. Daily dry matter (DM) intake and DM digestibility were 50±6 g kg⁻⁰·⁷⁵ d⁻¹ and 55±6% in rabbits and 59±11 g kg⁻⁰·⁷⁵ d⁻¹ and 61±3% in guinea pigs, respectively. Methane production was similar for both species (0.2...
Marliani G, Sprocatti I, Schiavoni G, Bellodi A, Accorsi PA.The increasing interest in animal welfare and the knowledge of equine physiological and ethological needs have led to the development of different types of horses' management and housing systems. The research presented here aimed to assess the daytime activity budget of horses. Focal animal sampling was used as an observational sampling method, and the five animals were observed for a total of 9920 minutes in the paddock and inside the stall. The results showed that horses spent most of the daytime in foraging behaviors, followed by resting behaviors, and locomotion. Social behaviors (s.e. al...
Clarke LL, Roberts MC, Argenzio RA.The association of feeding practices with the development of digestive disorders in horses has long been recognized, although the underlying mechanisms had been barely considered. The physiologic consequences of meal frequency may help to explain the relationship and prove to be of major significance in the induction of many conditions. Many Equidae kept for performance and leisure activities are fed high-energy, low-forage rations twice daily, with limited access to hay or grazing. Rapid ingestion of such meals stimulates a copious outpouring of upper alimentary secretions and results in tran...
Goodwin D, Davidson HP, Harris P.The restricted access to pasture experienced by many competition horses has been linked to the exhibition of stereotypic and redirected behaviour patterns. It has been suggested that racehorses provided with more than one source of forage are less likely to perform these patterns; however, the reasons for this are currently unclear. To investigate this in 4 replicated trials, up to 12 horses were introduced into each of 2 identical stables containing a single forage, or 6 forages for 5 min. To detect novelty effects, in the first and third trials the single forage was hay. In the second and fo...
Tassone S, Renna M, Barbera S, Valle E, Fortina R.Successful studies on in vitro digestibility measurement of feedstuffs with fecal inoculum have been reported for horses, whereas data on donkeys are currently lacking. In this study, we evaluated the use of the Daisy Incubator for in vitro digestibility measurement of feedstuffs using donkey feces as source of microbial inoculum. The method was tested using seven feedstuffs commonly used in donkey diets (alfalfa, bromegrass, ryegrass, and timothy hays; wheat bran and wheat straw; barley grains). Feces were obtained from four female donkeys, and incubations were carried out at 1-week interva...
Udén P, Rounsaville TR, Wiggans GR, Van Soest PJ.1. Digesta passage and retention were measured in heifers, sheep, goats, equines and rabbits of varying body-weights when given timothy (Phleum pratense) hay. 2. Two passage markers were compared, cobalt (III) ethylene diamine tetraacetate (CoEDTA) and chromiummordanted timothy fibre for liquid and solid phase respectively. Both markers were injected into the rumen of the ruminants and into the caecum of the equines and rabbits. 3. In ruminants, two different sets of rate constants (k1 and k2) were derived from a two-pool model for marker passage, using a graphical approach and a computer-base...
Muhonen S, Connysson M, Lindberg JE, Julliand V, Bertilsson J, Jansson A.The objective of this study was to investigate the effect of CP intake from 2 grass silage-only diets, differing in CP concentration, fed at similar DMI on the equine colon ecosystem after an abrupt feed change between the diets. Four adult right ventral colon-fistulated geldings were fed one silage-only diet high in CP (HP, 873 g of CP/d) and one diet providing recommended intakes (RP, 615 g of CP/d). An adaptation period of 15 d on either the HP or the RP diet was followed by 2 experimental periods when the diets were fed for 22 d each in a crossover design. Colon samples were taken before a...
Morrison PK, Newbold CJ, Jones E, Worgan HJ, Grove-White DH, Dugdale AH, Barfoot C, Harris PA, Argo CM.Obesity is an important equine welfare issue. Whilst dietary restriction is the most effective weight-loss tool, individual animals range in their weight-loss propensity. Gastrointestinal-derived bacteria play a fundamental role in host-health and have been associated with obesity and weight-loss in other species. This study evaluated the faecal microbiome (next-generation sequencing of 16S rRNA genes) of 15 obese Welsh Mountain pony mares, in the same 11-week period across 2 years (n = 8 Year 1; n = 7 Year 2). Following a 4-week acclimation period (pre-diet phase) during which t...
Cavallini D, Penazzi L, Valle E, Raspa F, Bergero D, Formigoni A, Fusaro I.Dry hay (composed of grass, legumes, or a mixture of the two) provides the primary source of alimentary fiber in stabled horses with limited access to fresh pasture. However, hay can also give rise to health problems in the horse, depending on the quality and quantity of its components. Pathologies may be rooted in biological problems, such as inadequate digestion disturbances, or reflect mechanical difficulties-for example, due to the presence of sharp plant parts that irritate the oral mucosa, or due to physical intake problems that inhibit consumption. Unwanted plants in the hay may cause s...
Devenport JA, Patterson MR, Devenport LD.The variability of most environments taxes foraging decisions by increasing the uncertainty of the information available. One solution to the problem is to use dynamic averaging, as do some granivores and carnivores. Arguably, the same strategy could be useful for grazing herbivores, even though their food renews and is more homogeneously distributed. Horses (Equus callabus) were given choices between variable patches after short or long delays. When patch information was current, horses returned to the patch that was recently best, whereas those without current information matched choices to ...
Selim S, Elo K, Jaakkola S, Karikoski N, Boston R, Reilas T, Särkijärvi S, Saastamoinen M, Kokkonen T.Obesity and insulin resistance have been shown to be risk factors for laminitis in horses. The objective of the study was to determine the effect of changes in body condition during the grazing season on insulin resistance and the expression of genes associated with obesity and insulin resistance in subcutaneous adipose tissue (SAT). Sixteen Finnhorse mares were grazing either on cultivated high-yielding pasture (CG) or semi-natural grassland (NG) from the end of May to the beginning of September. Body measurements, intravenous glucose tolerance test (IVGTT), and neck and tailhead SAT gene exp...
Borgia L, Valberg S, McCue M, Watts K, Pagan J.The aim of this study was to determine whether the glycaemic/insulinaemic responses to hay with non-structural carbohydrate (NSC, soluble carbohydrate) of 17% (HC), 10% (MC) or 4% (LC) differs in control horses and whether these responses differ between control and horses with polysaccharide storage myopathy (PSSM). Five clinically normal control horses and seven PSSM horses, all unfit and of Quarter Horse breeding (age 9.4 ± 3.4 years, body condition score range: 4.5-6). A crossover design compared the HC and LC hay, with horses randomly assigned to hay type for 5 days, and all horses fed th...
Argo CM, Dugdale AH, McGowan CM.The addition of hay soaking to current nutritional advice for weight loss management for equine obesity lacks clinical evidence. Twelve overweight/obese horses and ponies were used to test the hypothesis that feeding soaked hay at 1.25% of body mass (BM) daily as dry matter (DM) before soaking would elicit weight losses within the target 0.5-1.0% of BM weekly. Six animals were used to evaluate the impact of nutrient-leaching on the digestibility and daily intakes of dietary energy and nutrients. Soaked hay DM was corrected in accordance with the 'insoluble' ADF content of fresh and soaked hays...
