Hay is a primary forage source for horses, consisting of dried grasses or legumes harvested and stored for feeding. It serves as a significant component of the equine diet, providing essential fiber, energy, and nutrients necessary for maintaining digestive health and overall well-being. Common types of hay fed to horses include timothy, alfalfa, and orchard grass, each varying in nutritional content and suitability for different dietary needs. The quality and nutritional value of hay can be influenced by factors such as the plant species, stage of maturity at harvest, and storage conditions. This page compiles peer-reviewed research studies and scholarly articles that explore the composition, nutritional evaluation, and impact of hay on equine health and performance.
Guerrero JLS, Brito PHS, Ferreira MA, Arantes JA, Rusch E, Oliveira BVDS, Velasco-Bolaños J, Carregaro AB, Dória RGS.The prevalence of gastric disorders in high-performance horses, especially gastric ulceration, ranges from 50 to 90%. These pathological conditions have negative impacts on athletic performance and health. This study was designed to evaluate changes in gastric pH during a 24 h period and to compare gastrin concentrations at different time points in horses undergoing general inhalation anesthesia and dorsal recumbency. Twenty-two mixed-breed mares weighing 400 ± 50 kg and aged 8 ± 2 years were used. Of these, eight were fasted for 8 h and submitted to 90 min of general inhalation anesthesia i...
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...
Laroche N, Grimm P, Julliand S, Sorci G.The use of anthelminthic drugs has several drawbacks, including the selection of resistant parasite strains. Alternative avenues to mitigate the negative effects of helminth infection involve dietary interventions that might affect resistance and/or tolerance by improving host immunity, modulating the microbiota, or exerting direct anthelmintic effects. The aim of this study was to assess the impact of diet on strongyle infection in horses, specifically through immune-mediated, microbiota-mediated, or direct anthelmintic effects. Horses that were naturally infected with strongyles were fed eit...
Carslake HB, Pinchbeck GL, Argo CM, Dugdale AHA, McGowan CM.Glucagon-like peptide-1 (GLP-1), the principal incretin in horses, may play a role in the pathophysiology of insulin dysregulation (ID). This study aimed to describe its concentration in response to three preserved forages and four dynamic tests for ID in ponies. Twelve adult ponies of mixed ID status were given a meal of hay, soaked hay or haylage, an in-feed oral glucose test (OGT), oral sugar test (OST), an oral test using a proprietary breakfast cereal (WEET) or a combined glucose-insulin tolerance test (CGIT) weekly in a randomised cross-over study. Glucose, insulin and GLP-1 concentratio...
DeBoer M, Keener L, Layeux-Parks J, Schueller O, Johnson L, Martinson K.Hay nets are a commonly used management practice to increase intake time and reduce hay waste but may impact horse health. The objectives were to compare hay usage, dental wear, and dental conditions between horses fed with (NET) or without (CON) hay nets during a 2-year cross-over study. In September 2021, 13 mature adult horses were blocked by bodyweight (BW) and randomly assigned to the NET or CON treatments for one year. After one year (September 2022), horses switched treatments and the trial concluded in September 2023. Horses were housed in adjacent dry lots with shelter, ad libitum wat...
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...
Jentsch MC, Lübke S, Schrödl W, Volke D, Krizsan A, Hoffmann R, Kaiser-Thom S, Gerber V, Marti E, Wagner B, Schnabel CL.Severe equine asthma (SEA) is a common chronic disease of adult horses with characteristic recurrent airway obstruction and similarities to neutrophilic asthma in humans. As an extrinsic stimulus, hay dust exposure is a major risk factor and induces acute exacerbation in susceptible horses. However, single inducing agents of SEA have hardly been identified on a molecular basis. () is a common mold species in hay and has been described as a major provoking agent of SEA. Unassigned: Aiming to identify disease-relevant antigens, we analyzed using an immunoproteomics approach on two-dimensional ...
Kara K, Altınsoy A.Forages are widely used in horse diets. Different in vitro techniques are being tried to determine the fermentation levels of forages in the horse digestive tract. Objective: This study aimed to evaluate the digestion levels of four dry forages commonly used in horse nutrition: alfalfa herbage, meadow hay, wheat straw, and Italian ryegrass. In vitro total digestion (TDT), in vitro Sunvold-large intestine digestion (SDT) and in vitro Menke-large intestine digestion (MDT) techniques were compared. Methods: The study determined in vitro true dry matter digestion (T-DMD), in vitro true organic mat...
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...
Romano MC.Many popular ornamental shrubs are not only beautiful but also toxic when ingested in sufficient quantities. Common toxic landscaping shrubs in North America include yew (Taxus spp), oleander (Nerium oleander), and rhododendrons and azaleas (Rhododendron spp). Horses are often exposed when plant trimmings are placed within reach or discarded in pastures. Occasionally clippings or fallen leaves contaminate hay. Some plants are unpalatable unless dried and mixed with hay or lawn clippings but others are ingested more readily. In many cases, disease can be severe and treatment unrewarding; theref...
Mallicote MF, Medina CI, Xie H, Zilberschtein J, Atria S, Manzie M, Hernandez JA, MacKay RJ.To assess the therapeutic efficacy of acupuncture in combination with Chinese herbs for treatment of horses affected with anhidrosis. Methods: 44 horses affected with anhidrosis for up to 3 years' duration were enrolled. Inclusion required both compatible clinical signs and results of a quantitative intradermal terbutaline sweat test. Methods: Study horses were randomly allocated into 2 groups. Group 1 (n = 19) was treated with daily Chinese herbs and 4 weekly acupuncture sessions. Group 2 (n = 25) was given daily hay powder as a placebo and 4 weekly sham acupuncture sessions. Horses were test...
Drozdzewska K, Winter J, Barton AK, Merle R, Gehlen H.The basal (bACTH) and post-thyrotropin-releasing hormone stimulation concentration of adrenocorticotropin (pACTH) are recommended for diagnosis of pituitary pars intermedia dysfunction (PPID). Many factors influence bACTH (e.g., disease, age, month) and some affect the results only in autumn (e.g., breed, colour, sex). There are discrepancies about the impact of feeding on b/pACTH. Objective: To determine whether feeding, month, age, breed, colour, sex and body condition score affect b/pACTH. Methods: Prospective crossover. Methods: Sixty-one animals were divided into groups: healthy, PPID, tr...
Burron S, Richards T, McCorkell TC, Trevizan L, Puttick D, Ma DWL, Pearson W, Shoveller AK.Camelina (Camelina sativa) is a hardy, low-input oilseed crop that provides a rich source of the n-3 fatty acid, α-linolenic acid (ALA). The primary purpose of the present study was to assess the effects of dietary camelina oil (CAM) consumption on various health parameters, as compared to horses fed canola oil (OLA) or flax oil (FLX). Secondly, to determine how dietary CAM, FLX, and OLA alter circulating plasma total lipids across time. Thirty horses, from three separate herds, were used for this study [14.9 years ± 5.3 years; 544 ± 66 kg calculated BW (mean ± SD)]. After a 4-wee...
Richards T, Burron S, McCorkell TC, Trevizan L, Patterson K, Minikhiem D, Ma DWL, Pearson W, Shoveller AK.Camelina oil is derived from a low-input, high-yield crop and, in comparison to many other dietary fat sources currently used in equine diets, provides a greater amount of α-linolenic acid [ALA; (n-3)], than linoleic acid [LA; (n-6)]. However, no research exists assessing the effects of feeding camelina oil to horses in contrast to other commonly used oils. The objective of this study was to compare the effect of supplementing camelina oil to that of flaxseed and canola oil supplementation, on outcomes related to skin and coat health in horses. Thirty adult horses [23 mares, 7 geldings; 14.9 ...
Nava V, Licata P, Biondi V, Catone G, Gugliandolo E, Pugliese M, Passantino A, Crupi R, Aragona F.Horses are excellent bioindicators for the assessment of environmental pollution. The aim of this study was to evaluate the levels and potential bioaccumulation of 28 mineral elements in 75 horse whole blood samples collected from five pollution-prone areas of Sicily, Italy. A direct mercury analyzer (DMA-80) was used for Hg determination, and an inductively coupled plasma mass spectrometer (ICP-MS) for all other elements. A one-way ANOVA test, followed by Bonferroni's multiple comparison for post hoc comparison, was applied to assess statistically significant differences between mineral eleme...
Starrett A, Smith R, Urso PM, Urschel KL, Anderson MJ, Suagee-Bedore JK.Irregular wear patterns are theorized to cause poor feed digestion and weight loss in the horse. The objective of this study was to test the hypothesis that dental correction would increase postprandial nutrient concentrations and reduce fecal particle size (FPS) in clinically healthy mares. The study was conducted in 16 mares of mature age (4-17) who had not received dental care in the previous year. A diet consisting of ad libitum Coastal Bermudagrass hay and 1.36 kg of a pelleted feed was fed daily prior to and during the study. Eight mares received dental work and eight served as untreat...
Ford T, McAdams ZL, Townsend KS, Martin LM, Johnson PJ, Ericsson AC.The purpose of this study is to determine the effect of the partial replacement of dietary hay with sugar beet pulp (SBP) on the composition and predicted function of the fecal microbiota of healthy adult horses. Fecal samples were collected daily for 12 days from six adult horses after removal from pasture, including a five-day acclimation period, and a seven-day period following the introduction of SBP into their diet, and compared to six untreated horses over a comparable period. Fecal DNA was subjected to 16S rRNA amplicon sequencing and a longitudinal analysis was performed comparing the ...
Springer RW, Mason AC, Cross TD, Guay KA, Raub RH, Wellmann KB, Jones TN.With greater availability of hemp (Cannabis sativa L.) due to recent legislation, hempseed meal (HSM) should be evaluated as a potential feedstuff for livestock. The study objective was to evaluate the palatability of HSM in horses. Trial 1 used a modified 3 × 3 Latin Square design utilizing three geldings and three mares. Feeding periods (6d) consisted of two feedings/d with a washout phase (3d) before each treatment phase (3d). During treatment, horses were offered soybean meal pellets (SBM), rice bran pellets (RBP), or beet pulp pellets (BPP) in one bucket (500 g) and HSM in a second buc...
Velloso Alvarez A, Jose-Cunilleras E, Dorrego-Rodriguez A, Santiago-Llorente I, de la Cuesta-Torrado M, Troya-Portillo L, Rivera B, Vitale V....Real-time PCR is the diagnostic technique of choice for the diagnosis and control of equine herpesvirus-1 (EHV-1) in an outbreak setting. The presence of EHV-1 in nasal swabs (NS), whole blood, brain and spinal cord samples has been extensively described; however, there are no reports on the excretion of EHV-1 in urine, its DNA detection patterns, and the role of urine in viral spread during an outbreak. Objective: To determine the presence of EHV-1 DNA in urine during natural infection and to compare the DNA detection patterns of EHV-1 in urine, buffy coat (BC) and NS. Methods: Descriptive st...
Martin A, Lepers R, Vasseur M, Julliand S.Large amounts of high-starch concentrates are traditionally fed to horses in training. However, this has been associated with digestive or muscle diseases and behavioural modifications. In parallel, it has been demonstrated that horses fed high-fibre, low-starch diets achieve the same performance over an exercise test as the ones fed high-starch diets. However, whether the same performance level can be maintained over a longer training cycle is still being determined. This study aimed to compare the evolution in physical performance and cardiorespiratory responses of two groups of French Trott...
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....
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...
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...
Kranenburg LC, van der Poel SH, Warmelink TS, van Doorn DA, van den Boom R.Equine squamous gastric disease (ESGD) is common in horses and poses a serious welfare problem. Several risk factors have been identified and ESGD is routinely treated with omeprazole. Fourteen mares, previously used as embryo recipients and diagnosed with ESGD, were selected. Horses were confined to individual stalls, exercised once daily, and fed ad libitum hay, 1 kg of a low starch compound complementary feed and a mineral supplement. Half of the horses received a compound containing hydrolysed collagen (supplement) and the other half did not (control). At the start of the study, ESGD score...
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,...
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...
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...
McGreevy PD, Cripps PJ, French NP, Green LE, Nicol CJ.A greater knowledge of the effect of management factors is required to investigate the ontogeny of abnormal behaviour in the stabled horse. A postal survey of racehorse (flat) trainers yielded information about 22 yard and management factors. The relationship of the factors to the prevalence of abnormal behaviour was analysed by logistic regression. Management factors related to the time spent in the stable showed the strongest associations with stereotypic behaviour. The risk of horses performing abnormal behaviour increased: 1) as the amount of forage fell below 6.8 kg/day, 2) when bedding t...
Morrison PK, Newbold CJ, Jones E, Worgan HJ, Grove-White DH, Dugdale AH, Barfoot C, Harris PA, Argo CM.Gastrointestinal microbial communities are increasingly being implicated in host susceptibilities to nutritional/metabolic diseases; such conditions are more prevalent in obese and/or older horses. This controlled study evaluated associations between host-phenotype and the fecal microbiome / metabolome. Thirty-five, Welsh Mountain pony mares were studied across 2 years (Controls, = 6/year, 5-15 years, Body Condition Score (BCS) 4.5-6/9; Obese, = 6/year, 5-15 years, BCS > 7/9; Aged, = 6 Year 1; = 5 Year 2, ≥19 years old). Animals were individually fed the same hay to maintenance (2% bo...
Ramseyer A, Gaillard C, Burger D, Straub R, Jost U, Boog C, Marti E, Gerber V.Environment and genetics influence the manifestation of recurrent airway obstruction (RAO), but the associations of specific factors with mild, moderate, and severe clinical signs are unknown. Objective: We hypothesized that sire, feed, bedding, time outdoors, sex, and age are associated with clinical manifestations of mild, moderate, and severe lower airway disease. Methods: Direct offspring of 2 RAO-affected Warmblood stallions (F1S1, n = 172; F1S2, n = 135); maternal half-siblings of F1S1 (mHSS1, n = 66); and an age-matched, randomly chosen control group (CG, n = 33). Methods: A standardize...
Hotchkiss JW, Reid SW, Christley RM.Recurrent airway obstruction (RAO) is a commonly encountered respiratory condition of horses. Despite this, the epidemiology of this predominately manageable and reversible disease in Great Britain has been largely ignored. Objective: To estimate the prevalence of RAO in the general horse population of Great Britain and to investigate possible risk factors for RAO associated with management or early life. Methods: Horse owners were surveyed using a self-administered postal questionnaire that contained a risk-screening questionnaire (RSQ) designed to identify horses with RAO. These owners were ...
Harris PA, Ellis AD, Fradinho MJ, Jansson A, Julliand V, Luthersson N, Santos AS, Vervuert I.The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the p...
Pirie RS, Collie DD, Dixon PM, McGorum BC.Equine heaves is a naturally occurring organic dust-induced asthma characterized by airway neutrophilia, mucus hypersecretion and obstructive lung dysfunction. However, the relative role of different dust components in disease severity remains unclear. Objective: This study investigated the relative contribution of inhaled endotoxin and organic dust particulates (mainly mould spores) in inducing heaves in heaves-susceptible horses. Methods: Control and heaves-susceptible horses received inhalation challenges with hay dust suspension (HDS) before and after lipopolysaccharide (LPS) depletion. He...
Ivester KM, Couëtil LL, Moore GE, Zimmerman NJ, Raskin RE.Inflammatory airway disease (IAD) in horses is a widespread, performance-limiting syndrome believed to develop in response to inhaled irritants in the barn environment. Objective: To evaluate changes in bronchoalveolar lavage fluid (BALF) cytology and exposure to particulates, endotoxin, and ammonia during horses' first month in training. Methods: Forty-nine client-owned 12- to 36-month-old Thoroughbred horses entering race training. Methods: In this prospective cohort study, a convenience sample of horses was assigned to be fed hay from a net (n = 16), whereas the remaining horses were fed ha...
Hudson JM, Cohen ND, Gibbs PG, Thompson JA.To determine whether specific feeding practices were associated with development of colic in horses. Methods: Prospective matched case-control study. Methods: 364 horses examined by veterinarians in private practice in Texas because of colic (cases; n = 182) or any other reason (controls; 182). Methods: Participating veterinarians were sent forms at the beginning of the study to collect information on signalment, feeding management practices, farm management practices, and preventive medical treatments. Case and control horses were compared by use of conditional logistic regression to identify...
Cortinovis C, Caloni F.Alkaloids, nitrogen-containing secondary plant metabolites, are of major interest to veterinary toxicology because of their occurrence in plant species commonly involved in animal poisoning. Based on epidemiological data, the poisoning of cattle and horses by alkaloid-containing plants is a relatively common occurrence in Europe. Poisoning may occur when the plants contaminate hay or silage or when forage alternatives are unavailable. Cattle and horses are particularly at risk of poisoning by Colchicum autumnale (meadow saffron), Conium maculatum (poison hemlock), Datura stramonium (jimson wee...
Gerber V, Lindberg A, Berney C, Robinson NE.Mucus accumulation and neutrophilic inflammation in the airways are hallmarks of heaves. Endoscopically visible mucus accumulations, however, have not been studied during exposure to dusty hay and allergens (ie, environmental challenge). We hypothesized that (1) heaves-affected horses have increased mucus accumulation compared with controls, (2) mucus accumulations increase in heaves-affected horses during environmental challenge, and (3) environmental challenge also induces neutrophilic inflammation and mucus accumulation in control horses. Mucus accumulation was graded endoscopically (mucus ...
Harlow BE, Lawrence LM, Hayes SH, Crum A, Flythe MD.Starch from corn is less susceptible to equine small intestinal digestion than starch from oats, and starch that reaches the hindgut can be utilized by the microbiota. The objective of the current study was to examine the effects of starch source on equine fecal microbiota. Thirty horses were assigned to treatments: control (hay only), HC (high corn), HO (high oats), LC (low corn), LO (low oats), and LW (low pelleted wheat middlings). Horses received an all-forage diet (2 wk; d -14 to d -1) before the treatment diets (2 wk; d 1 to 14). Starch was introduced gradually so that horses received 50...
Raspa F, Vervuert I, Capucchio MT, Colombino E, Bergero D, Forte C, Greppi M, Cavallarin L, Giribaldi M, Antoniazzi S, Cavallini D, Valvassori E....Horses are often fed high amounts of starch in their diets despite the well-established benefits of a fibre-based diet to promote gut health and animal welfare. The aim of the present study was to compare the effects of two different diets - one based on high amounts of starch (HS) vs. one base on high amounts of fibre (HF) - on specific parameters of the gut environment across different intestinal compartments of the horse digestive tract. To this end differences in the gastrointestinal environment between HS vs. HF fed horses were assessed in terms of dry matter, organic matter and ash conte...
Grimm P, Combes S, Pascal G, Cauquil L, Julliand V.Starchy diets can induce hindgut dysbiosis in horses. The present study evaluated the impact of a yeast (Saccharomyces cerevisiae) and microalgae (Aurantiochytrium limacinum) supplementation on caecal, colonic and faecal microbial ecosystem and on blood inflammatory parameters of horses fed high-fibre or high-starch diets. Six fistulated geldings in a 2 × 2 Latin-square design were alternatively supplemented and received during each period 100 % hay (4 weeks) followed by a 56/44 hay/barley diet (3 weeks). Caecal, colonic and faecal samples were collected 4 h after the morning meal three times...
Dauvillier J, Ter Woort F, van Erck-Westergren E.Fungi contribute to the inflammatory response of lungs in horses with recurrent airway obstruction and in some forms of asthma in humans. The role of fungi in inflammatory airway disease (IAD) has not been assessed. Objective: Evaluate the prevalence of fungi in the respiratory samples of horses diagnosed with IAD, describe clinical signs associated with the presence of fungi in respiratory samples, and assess the risk factors associated with IAD and with the presence of fungi in the airways. Methods: Seven-hundred thirty-one active horses referred to a specialized ambulatory practice for sign...
Gerber V, Baleri D, Klukowska-Rötzler J, Swinburne JE, Dolf G.Mode of inheritance of equine recurrent airway obstruction (RAO) is unknown. Objective: Major genes are responsible for RAO. Methods: Direct offspring of 2 RAO-affected Warmblood stallions (n = 197; n = 163) and a representative sample of Swiss Warmbloods (n = 401). Methods: One environmental and 4 genetic models (general, mixed inheritance, major gene, and polygene) were tested for Horse Owner Assessed Respiratory Signs Index (1-4, unaffected to severely affected) by segregation analyses of the 2 half-sib sire families, both combined and separately, using prevalences estimated in a representa...
Hansen NC, Avershina E, Mydland LT, Næsset JA, Austbø D, Moen B, Måge I, Rudi K.It is well known that nutrient availability can alter the gut microbiota composition, while the effect on diversity and temporal stability remains largely unknown. Methods: Here we address the equine caecal microbiota temporal stability, diversity, and functionality in response to diets with different levels of nutrient availability. Hay (low and slower nutrient availability) versus a mixture of hay and whole oats (high and more rapid nutrient availability) were used as experimental diets. Results: We found major effects on the microbiota despite that the caecal pH was far from sub-clinical ac...
Robinson NE, Karmaus W, Holcombe SJ, Carr EA, Derksen FJ.Although subclinical airway inflammation is thought to be common in horses, there is little information on its prevalence and none on risk factors. Objective: To determine the prevalence and risk factors for an increased number of inflammatory cells and for mucus accumulation in the trachea of pleasure horses. Methods: Horses (n = 266) in stables (n = 21) in Michigan were examined endoscopically, once in winter and once in summer 2004. Visible tracheal mucoid secretions were graded 0-5 and inflammatory cell numbers counted in a tracheal lavage sample. Information collected about each horse inc...
Dougal K, Harris PA, Girdwood SE, Creevey CJ, Curtis GC, Barfoot CF, Argo CM, Newbold CJ.Twelve mature (aged 5-16 years) horses and ponies of mixed breed and type were fed restricted (1.25% BM Dry matter) quantities of one of two fiber based diets formulated to be iso-caloric. Diet 1 comprised of 0.8% body mass (BM) of chaff based complete feed plus 0.45% BM low energy grass hay (the same hay used for both diets). Diet 2 comprised 0.1% BM of a nutrient balancer plus 1.15% BM grass hay. Fecal samples were collected at week 10 and week 16. DNA was extracted and the V1-V2 regions of 16SrDNA were 454-pyrosequenced to investigate the bacterial microbiome of the horse. The two most abun...
Cortinovis C, Caloni F.This review focuses on some of the most important poisonous plants in Europe and provides an overview of the poisoning episodes that have occurred in European countries. Poisoning of livestock and companion animals by plants is a relatively common occurrence. In Europe livestock and horses are commonly poisoned by Datura stramonium (Jimson weed), Senecio spp. (ragworts and groundsels), Quercus spp. (oak), Taxus baccata (European yew), Nerium oleander (oleander), Pteridium aquilinum (bracken fern), Robinia pseudoacacia (black locust) and Rhododendron spp. (rhododendrons and azaleas). Poisoning ...
Cohen ND, Gibbs PG, Woods AM.To determine whether dietary and other management factors were associated with development of colic in horses. Methods: Prospective matched case-control study. Methods: 2,060 horses examined by veterinarians in private practice in Texas for colic and noncolic emergencies. Methods: Each month for 12 months, participating veterinarians were sent forms to collect information on 1 horse with colic and 1 horse that received emergency treatment for a condition other than colic, information collected included signalment, farm management and characteristics, diet, medical and preventive medical factor...
Mellor DJ, Love S, Walker R, Gettinby G, Reid SW.Details of the management, feeding, level of activity and routine health care of horses in Scotland and the five northernmost counties in England were recorded through a stratified random sample of horse owners who had responded to a previous survey. Sixty-eight per cent of the horses were kept where their owners resided, and 32 per cent were kept away from the owner's home. More than 99 per cent were turned out to grazing for at least part of the year and 81 per cent were stabled for at least part of the time, most commonly bedded on straw (50 per cent) or shavings (34 per cent). Hay was fed ...
Pacholewska A, Jagannathan V, Drögemüller M, Klukowska-Rötzler J, Lanz S, Hamza E, Dermitzakis ET, Marti E, Leeb T, Gerber V.Recurrent airway obstruction (RAO) is a common and potentially debilitating lower airway disease in horses, which shares many similarities with human asthma. In susceptible horses RAO exacerbation is caused by environmental allergens and irritants present in hay dust. The objective of this study was the identification of genes and pathways involved in the pathology of RAO by global transcriptome analyses in stimulated peripheral blood mononuclear cells (PBMCs). We performed RNA-seq on PBMCs derived from 40 RAO affected and 45 control horses belonging to three cohorts of Warmblood horses: two h...
Pirie RS, Dixon PM, Collie DD, McGorum BC.To investigate whether inhaled endotoxin contributes to airway inflammation and dysfunction in stabled horses, control (n = 6) and asymptomatic heaves (previously termed chronic obstructive pulmonary disease)-susceptible (n = 7) horses were given inhalation challenges with 20, 200 and 2,000 microg of soluble Salmonella typhimurium Ra60 lipopolysaccharide (LPS). LPS inhalation induced a dose-dependent neutrophilic airway inflammatory response in both groups. Inhalation with 2,000 microg of LPS also induced detectable lung dysfunction in the heaves group. LPS inhalation did not alter clinical sc...
Tesarowski DB, Viel L, McDonell WN.To evaluate the degree of reproducibility in clinical variables, blood gas measurements, and lung function variables, and the changes in these variables caused by exposure to moldy hay in naturally sensitized and control horses. Methods: The magnitude of variation in arterial blood gas and pulmonary function measurements were evaluated in a model of naturally acquired heaves. Horses with heaves and similarly aged control horses were studied prior to moldy hay challenge and again after the horses with heaves manifested clinical signs of airway obstruction. This cycle of testing was repeated 3 t...
Bonin SJ, Clayton HM, Lanovaz JL, Johnston T.Previous studies have suggested that temporomandibular joint (TMJ) kinematics depend on the type of food being masticated, but accurate measurements of TMJ motion in horses chewing different feeds have not been published. Objective: The temporomandibular joint has a larger range of motion when horses chew hay compared to pellets. Methods: An optical motion capture system was used to track skin markers on the skull and mandible of 7 horses as they chewed hay and pellets. A virtual marker was created on the midline between the mandibles at the level of the 4th premolar teeth to represent the ove...
Clements JM, Pirie RS.Traditional methods of measuring airborne dust concentrations (ADC) in animal housing have included the collection of dust onto pre-weighed filters permitting the calculation of mean, not maximum, ADC. However real-time continuous particle monitors are advantageous in identifying short duration elevations in ADC which may be detrimental to equine respiratory health in the face of a relatively low mean ADC. These monitors have not previously been used to measure ADC in equine stables. Comparisons of a filter-based sampler and a real-time continuous particle monitor revealed no significant diffe...
Bamford NJ, Potter SJ, Baskerville CL, Harris PA, Bailey SR.The importance of including exercise with dietary modification for the management of obese equids is not clearly understood. Objective: To evaluate the effect of a practical low-intensity exercise regimen, in addition to dietary restriction, on indices of insulin sensitivity (SI) and plasma adipokine concentrations in obese equids. Methods: Twenty-four obese (body condition score [BCS] ≥ 7/9) horses and ponies. Methods: Over a 12-week period, animals received either dietary restriction only (DIET) or dietary restriction plus low-intensity exercise (DIET+EX). All animals were provided wit...
Vandenput S, Istasse L, Nicks B, Lekeux P.Standardized methods were used to make quantitative and qualitative assessments of respirable dust and aeroallergens in feed and bedding for horses. Concentrations of airborne dust were measured by using a Rion particle counter, and levels of major aeroallergens implicated in chronic obstructive pulmonary disease were measured by using an Andersen sampler. Laboratory conditions allowed comparison of the different sources of forage, supplements, and bedding without external influences such as ventilation, external temperature and horse activity affecting the result. Grass silages of approximate...
Moore-Colyer MJ, Lumbis K, Longland A, Harris P.Five different hays were used to determine the effect of 5 different soaking and steaming treatments on the water soluble carbohydrate and microbial (bacteria and mould) contents of UK hay. Hays were subjected to the following 5 treatments: 1. Dry; 2. Steamed for 50 minutes in the Haygain- 600 steamer; 3. Soaked in water at 16°C for 9 hours; 4. Steamed then soaked and 5. Soaked then steamed. Post treatment hays were tested for water soluble carbohydrates, bacteria and mould contents. Differences between means were determined using ANOVA and least significant difference with hay (5), bale (3) ...
Franchini M, Gill U, von Fellenberg R, Bracher VD.To analyze effects of hay dust exposure on interleukin-8 (IL-8) concentration, percentage of neutrophils, and neutrophil chemotactic activity in bronchoalveolar lavage fluid (BALF) of horses with chronic obstructive pulmonary disease (COPD). Methods: 16 healthy horses and 29 horses with COPD. Methods: IL-8 concentration, percentage of neutrophils, and neutrophil chemotactic activity in BALF were measured. Values were analyzed with respect to hay dust exposure. These variables were also measured in 5 asymptomatic horses with COPD after the induction of clinical signs by changing feed from silag...
