Pasture and horses involve the study and management of grazing environments and their impact on equine health, nutrition, and behavior. Pastures serve as a primary source of forage, providing essential nutrients and contributing to the overall well-being of horses. Factors such as pasture composition, quality, and management practices influence the nutritional intake and health of grazing horses. Research in this area often focuses on optimizing pasture conditions to support equine dietary needs, prevent overgrazing, and manage pasture-related health issues such as laminitis. This page compiles peer-reviewed research studies and scholarly articles that explore the relationship between pasture management and equine health, including topics on forage quality, grazing behavior, and pasture maintenance strategies.
Nostell K, Lindåse S, Winqvist E, Bröjer J.Obesity is associated with insulin resistance, vascular dysfunction and altered cortisol metabolism both in humans and in horses. Objective: Evaluate the effect of weight gain induced by a haylage diet low in nonstructural carbohydrates (NSC) on insulin sensitivity, blood pressure and serum cortisol concentrations. Methods: In vivo experiment. Methods: Nine adult Standardbred mares fed a fat supplemented haylage diet at 250% of the horses' daily metabolisable energy requirements for 22 weeks. Horses were then turned out on pasture for 4 weeks. Insulin sensitivity (SI ) was measured before an...
Williams CA, Kenny LB, Weinert JR, Sullivan K, Meyer W, Robson MG.The objective of this study was to determine whether rotational grazing generates horse, pasture, or cost benefits over continuous grazing. The study established two replicates (1.57 ha each) of rotational (R; four grazing sections and a stress lot per replicate, where horses were fed a moderate quality grass hay at 2% of body weight when not grazing) and continuous (C) grazing systems (treatments). Twelve Standardbred mares were grazed for an overall stocking rate of 0.52 ha/horse ( = 3 in each pasture). Recommended management practices for each grazing system were followed for 27 mo includin...
Fitzgerald DM, Spence RJ, Stewart ZK, Prentis PJ, Sillence MN, de Laat MA.The equine microbiome can change in response to dietary alteration and may play a role in insulin dysregulation. The aim of this study was to determine the effect of adding pasture to a hay diet on the faecal bacterial microbiome of both healthy and insulin-dysregulated ponies. Faecal samples were collected from 16 ponies before and after dietary change to enable bacterial 16S rRNA sequencing of the V3-V4 region. The dominant phyla in all samples were the Firmicutes and Bacteroidetes. The evenness of the bacterial populations decreased after grazing pasture, and when a pony was moderately insu...
Saastamoinen M, Särkijärvi S, Valtonen E.The main horse phosphorus excretion pathway is through the dung. Phosphorus originating from animal dung and manure has harmful environmental effects on waters. The number of horses has increased in many countries, and several studies have pointed that leaching of P from horse paddocks and pastures are hotspots for high P leaching losses. The hypothesis was that feeding regimes might influence phosphorus digestibility and excretion in feces, and therefore the environmental impact of horse husbandry. A digestibility experiment was conducted with six horses fed six forage-based diets to study ph...
Maisonpierre IN, Sutton MA, Harris P, Menzies-Gow N, Weller R, Pfau T.Accelerometry is an accepted means of quantifying human physical activity. Quantitative physical activity tracking could be beneficial for studies into equine health and disease prevention, for example in relation to obesity management. Objective: Validate accelerometer use in grazing horses, determine between-day repeatability, and assess the effects of pasture size on time budget (i.e. duration in each activity category). Methods: Proof of concept. Methods: Accelerometers (ActiGraph) were positioned at the poll. Horses underwent 5 min of observed activity in three categories: standing, graz...
Lazzerini N, Coulon A, Simon L, Marchina C, Noost B, Lepetz S, Zazzo A.Carbon and nitrogen stable isotope time series performed in continuously growing tissues (hair, tooth enamel) are commonly used to reconstruct the dietary history of modern and ancient animals. Predicting the effects of altitudinal mobility on animal δ C and δ N values remains difficult as several variables such as temperature, water availability or soil type can contribute to the isotope composition. Modern references adapted to the region of interest are therefore essential. Methods: Between June 2015 and July 2018, six free-ranging domestic horses living in the Mongolian Altaï were fitte...
Yang J, Wang Y, Cui X, Zhang Y, Yu Z.Huge numbers of microorganisms reside in livestock faeces and constitute one of the most complex microbial ecosystems. Here, faecal microbial communities of three typical livestock in Xilingol steppe grassland, i.e. sheep, cattle, and horse, were investigated by Illumina MiSeq sequencing and quantitative real-time polymerase chain reaction (qPCR). Firmicutes and Bacteroidetes comprised the majority of bacterial communities in three livestock faeces. Sordariomycetes, Leotiomycetes, and Dothideomycetes were dominant in fungal communities, as well as Methanobacteria and Methanomicrobia were domin...
Votion DM, Habyarimana JA, Scippo ML, Richard EA, Marcillaud-Pitel C, Erpicum M, Gustin P.Equine atypical myopathy in Europe results from hypoglycin A (HGA) exposure through the ingestion of samaras or seedlings of the sycamore maple tree. This pilot study aimed at better defining sources of HGA intoxication in spring. Samaras fallen on the ground and then seedlings were collected at two-week intervals from sycamore, Norway, and field maple trees over the spring 2016. In early April, rainwater from wet seedlings collected after a rainy night was harvested to be analysed. Mid-May, samaras of the box elder, common ash, and inflorescences of sycamore maples were collected on the tree....
De La Torre U, Henderson JD, Furtado KL, Pedroja M, Elenamarie O, Mora A, Pechanec MY, Maga EA, Mienaltowski MJ.A healthy gastrointestinal (GI) tract with a properly established microbiota is necessary for a foal to develop into a healthy weanling. A foal's health can be critically impacted by aberrations in the microbiome such as with diarrhea which can cause great morbidity and mortality in foals. In this study, we hypothesized that gut establishment in the foal transitioning from a diet of milk to a diet of grain, forage, and pasture would be detectable through analyses of the fecal microbiotas. Fecal samples from 37 sets of foals and mares were collected at multiple time points ranging from birth to...
Hansen S, Klintoe K, Austevoll M, Baptiste KE, Fjeldborg J.Icelandic horses are often stabled in loose-housing systems, and to date this type of stabling has not been evaluated with regard to its potential impact on respiratory health. The objective was to assess if differences in management systems (eg, conventional stable, loose housing and pasture only) affect the degree of airway inflammation, evaluated by cytology of tracheal aspirate (TA) and bronchoalveolar lavage (BAL) fluid. In total, 84 Icelandic horses (aged 8.1±4.6 years) housed under three different management systems (conventional stables [n=29], loose-house systems [n=29] and pasture [...
Espunyes J, Lurgi M, Büntgen U, Bartolomé J, Calleja JA, Gálvez-Cerón A, Peñuelas J, Claramunt-López B, Serrano E.Changes in land-use and climate affect the distribution and diversity of plant and animal species at different spatiotemporal scales. The extent to which species-specific phenotypic plasticity and biotic interactions mediate organismal adaptation to changing environments, however, remains poorly understood. Woody plant expansion is threatening the extent of alpine grasslands worldwide, and evaluating and predicting its effects on herbivores is of crucial importance. Here, we explore the impact of shrubification on the feeding efficiency of Pyrenean chamois (Rupicapra p. pyrenaica), as well as ...
González-Medina S, Montesso F, Chang YM, Hyde C, Piercy RJ.Several pasture management strategies have been proposed to avoid hypoglycin A (HGA) intoxication in horses, but their efficacy has never been investigated. Objective: To evaluate the effect of mowing and herbicidal spraying on HGA content of sycamore seedlings and the presence of HGA in seeds and seedlings processed within haylage and silage. Methods: Experimental study. Methods: Groups of seedlings were mowed (n = 6), sprayed with a dimethylamine-based (n = 2) or a picolinic acid-based herbicide (n = 1). Seedlings were collected before intervention, and at 48 h, 1 and 2 weeks after. ...
Tirosh-Levy S, Gottlieb Y, Apanaskevich DA, Mumcuoglu KY, Steinman A.Ticks are important ectoparasites of horses that can affect animal welfare and vector several infectious, including zoonotic, diseases. In order to investigate the species distribution, epidemiology and seasonal dynamics of ticks infesting horses in Israel, 3267 ticks were collected from 396 horses in 24 farms across the country from July 2014 to June 2015. Results: Ticks were found on 50% of the farms and on 25% of the horses, with Hyalomma being the most prevalent genus (70% of ticks). Pasture was the most prominent risk factor for tick infestation (99% of ticks, P < 0.001), and is repres...
Karlíková R, Široká J, Mech M, Friedecký D, Janečková H, Mádrová L, Hrdinová F, Drábková Z, Dobešová O, Adam T, Jahn P.The case of atypical myopathy (AM) in newborn Haflinger foal with clinical signs of depression and weakness appearing 6 hours after birth resulting in recumbency 12 hours after birth is described. The foal's dam was diagnosed with AM in the 6th month of gestation based on clinical signs of a myopathy, elevated serum activity of creatine kinase, metabolomic analysis and the presence of methylenecyclopropyl acetyl carnitine (MCPA-carnitine) in the blood. At the time of delivery, the mare was grazing on a pasture near sycamore trees but was free of clinical signs of AM. Metabolomic analysis of th...
Nielsen MK, Branan MA, Wiedenheft AM, Digianantonio R, Scare JA, Bellaw JL, Garber LP, Kopral CA, Phillippi-Taylor AM, Traub-Dargatz JL.Equine strongyle parasites are considered ubiquitous in grazing equids across the world, and cyathostomin parasites are known pathogens causing well-described disease complexes in horses. Decades of intensive anthelmintic treatments have led to anthelmintic resistance in cyathostomins, and current recommendations are to lower treatment intensity and base control strategies on fecal egg count surveillance. Little is known about risk factors associated with strongyle parasite egg shedding patterns in the United States equine population, as the most recent national survey was conducted 20 years a...
Kenny LB, Ward D, Robson MG, Williams CA.Many methods exist for estimating species composition, but few studies compare those useful in improved horse pastures. The objective of this study was to examine 4 techniques for estimating desirable forage species composition in 2 cool-season horse pastures based on prevalence estimates, repeatability, bias, and practicality, and to select a method for use in a subsequent grazing study. The techniques included Equine Pasture Evaluation Disc (EPED), Line-Point Intercept with 3 transects of 50 observations each (LPI 3-50), LPI with 5 transects of 30 observations each (LPI 5-30), and Step Point...
Carranza J, Yoong WA, Vergara BC, Briones A, Mateos C.Reproductive phenology is an important trait subjected to natural selection. Current horses in America belong to the Palearctic original populations after being introduced by European colonizers. Photoperiod variation is the main environmental factor for the adjustment of reproductive timing in horses, but is absent in equatorial areas. Here we hypothesize that seasonality of green-grass availability may influence breeding phenology in equatorial regions. We used data of 929 services to mares from 2006 to 2011 in a thoroughbred equine exploitation in Ecuador that experienced strong grass seaso...
Cox AH, Amador JA.Historically, much of the New England landscape was converted to pasture for grazing animals and harvesting hay. Both consumer demand for local sustainably produced food, and the number of small farms is increasing in RI, highlighting the importance of characterizing the effects livestock have on the quality of pasture soils. To assess how livestock affect pasture on Charlton and Canton soils series in RI, we examined soil quality in farms raising beef cattle (Bos taurus), sheep (Ovis aries), and horses (Equus ferus caballus), using hayed pastures as a control. We sampled three pastures per li...
Odriozola ER, Rodríguez AM, Micheloud JF, Cantón GJ, Caffarena RD, Gimeno EJ, Bodega JJ, Gardey P, Iseas FB, Giannitti F.Solanum glaucophyllum, a toxic plant known for its calcinogenic effects, causes enzootic calcinosis in ruminant and monogastric animals. We describe an outbreak of enzootic calcinosis that occurred in a herd of 110 horses grazing pastureland heavily contaminated with S. glaucophyllum in Buenos Aires province, Argentina. Ten horses developed clinical signs, and 6 horses died. Clinical signs included abnormal gait (stiff-legged action, short strides), stiffness, thoracolumbar kyphosis, reluctance to move, wide stance, chronic weight loss, weakness, recumbency, and difficulty standing. Autopsy of...
Kaczensky P, Burnik Šturm M, Sablin MV, Voigt CC, Smith S, Ganbaatar O, Balint B, Walzer C, Spasskaya NN.The Przewalski's horse (Equus ferus przewalskii), the only remaining wild horse within the equid family, is one of only a handful of species worldwide that went extinct in the wild, was saved by captive breeding, and has been successfully returned to the wild. However, concerns remain that after multiple generations in captivity the ecology of the Przewalski's horse and / or the ecological conditions in its former range have changed in a way compromising the species' long term survival. We analyzed stable isotope chronologies from tail hair of pre-extinction and reintroduced Przewalski's horse...
Sato F, Tanabe T, Murase H, Tominari M, Kawai M.Global positioning system (GPS) units are now lightweight and compact. They have proven useful for analyzing the behavioral characteristics of horses in pastures. Because the GPS records data in latitude and longitude, it may be feasible to calculate the distance between GPS units. The present study aimed to confirm the applicability of GPS units in behavioral studies on horses. For this, we analyzed the accuracy of the distances calculated from GPS units using Hubeny's distance formula and of the monthly changes in interindividual distances obtained from GPS units worn by Thoroughbred dams an...
Munday JS, Finch SC, Vlaming JB, Sutherland BL, Fletcher LR.To investigate whether Mediterranean tall fescue (Lolium arundinaceum (Schreb.) Darbysh. (syn Festuca arundinacea)) infected with selected fungal endophytes (Epichloë coenophiala (formerly Neotyphodium coenophialum)) caused equine fescue oedema when grown in New Zealand, and to examine the pathological changes associated with this intoxication. Methods: Horses were grazed on Mediterranean tall fescue that was infected with the endophytes AR542 (n=2), or AR584 (n=3), or Mediterranean tall fescue that was endophyte-free (n=2). Blood samples were taken up to 7 days after the start of feeding to ...
Menzies-Gow NJ, Harris PA, Elliott J.Certain individuals appear to be predisposed to recurrent pasture-associated laminitis. Previous studies have predominantly investigated risk factors only after disease occurrence. Objective: To investigate risk factors for pasture-associated laminitis prior to disease occurrence. Methods: Prospective cohort study. Methods: Non-laminitic ponies aged ≥7 years were recruited. Body condition score (BCS), height, weight, crest height and thickness were measured and an overnight dexamethasone suppression test performed. Plasma or serum adiponectin, leptin, triglyceride, basal insulin, insulin pos...
Gomez DE, Valberg SJ, Magdesian KG, Hanna PE, Lofstedt J.This report describes a case of severe rhabdomyolysis in a pregnant mare associated with histopathologic and biochemical features of both selenium deficiency and acquired multiple acyl-CoA dehydrogenase deficiency (MADD) due to seasonal pasture myopathy (SPM). This case highlights the importance of assessing plasma selenium levels in horses with clinical signs of pasture myopathy as this deficiency may be a contributing or exacerbating factor. Déficience multiple acquise de déshydrogénase acyl-CoA et carence en sélénium marquée causant une rhabdomyolyse grave chez un cheval. Ce rapport d...
Bockisch F, Aboling S, Coenen M, Vervuert I.Vitamin-D intoxication by yellow oat grass is often reported under the syndrome of enzootic calcinosis in ruminants in the upper regions of the Alps. The intake of Trisetum flavescens in ruminants and horses induces calcification of soft tissue, including vessels, tendons and ligaments, lung, heart and kidneys. Clinical symptoms, including a reluctance to move, inappetence, body-weight loss and impaired organ function, are frequently observed. To date, there are only a very few case reports about yellow-oat-grass intoxication in horses. The present case report describes Vitamin-D intoxication ...
Sokół R, Michalski MM.The presence of Hippobosca equina strongly influences the behaviour and health status of horses. The aim of the study was to analyse the invasion dynamics of the forest fly in Polish primitive horses (Equus caballus gmelini) in the Popielno Forest Reserve (northeastern Poland). Observations were carried out from May to September, every two weeks for two consecutive years (2012 and 2013) in five study groups: in 11-12-year-old mares with foals, 6-7-year-old leading stallions, 1.5-year-old fillies, 1.5-year-old colts and 9-10-year-old working geldings. Adult H. equina were counted in the preferr...
Giles SL, Nicol CJ, Rands SA, Harris PA.Nuchal crest adiposity in horses and ponies has been associated with an enhanced risk of metabolic health problems. However, there is no current information on the prevalence of, and risk factors specific to, nuchal crest adiposity in horses and ponies. In addition, the cresty neck score has not previously been utilised across different seasons within a UK leisure population, it is not know whether nuchal crest adiposity shows the same seasonal trends as general obesity. Results: A Cresty Neck Score (CNS, 0-5) was given to 96 horses with access to pasture (>6 h per day) at the end of winter a...
Robinson B, Gummow B.A disease outbreak investigation was conducted in western Queensland to investigate a rare suspected outbreak of pyrrolizidine alkaloid (PA) toxicosis in horses. Thirty five of 132 horses depastured on five properties on the Mitchell grass plains of western Queensland died in the first six months of 2010. Clinical-pathological findings were consistent with PA toxicosis. A local variety of Crotalaria medicaginea was the only hepatotoxic plant found growing on affected properties. Pathology reports and departure and arrival dates of two brood mares provided evidence of a pre wet season exposure ...
Reinemeyer CR, Prado JC, Andersen UV, Nielsen MK, Schricker B, Kennedy T.Strongylid infections are ubiquitous in grazing horse populations. Infections with cyathostomin (small strongyle) and strongylin (large strongyle) nematodes have long been associated with clinical disease in horses, but little is known about their subclinical impact. A masked, randomized, controlled study was conducted to evaluate the effects of daily administration of pyrantel tartrate on body condition scores, weight gain, fecal egg counts, and total worm counts of young horses repeatedly inoculated with strongylid larvae. Twenty eight immature horses were treated with larvicidal anthelminti...
Sokół R, Michalski MM.The presence of Hippobosca equina strongly influences the behaviour and health status of horses. The aim of the study was to analyse the invasion dynamics of the forest fly in Polish primitive horses (Equus caballus gmelini) in the Popielno Forest Reserve (northeastern Poland). Observations were carried out from May to September, every two weeks for two consecutive years (2012 and 2013) in five study groups: in 11-12-year-old mares with foals, 6-7-year-old leading stallions, 1.5-year-old fillies, 1.5-year-old colts and 9-10-year-old working geldings. Adult H. equina were counted in the preferr...
Becvarova I, Pleasant RS, Thatcher CD.Veterinarians are a primary source of nutritional information and advice for horse owners. This article reviews methods for clinical assessment of nutritional status and feeding programs that can be applied to an individual horse or group of horses. Physical examination, including measurement of body weight and evaluation of body condition score, estimation of nutrient requirements and the nutrient content of the horse's diet, and evaluation of the feeding method are important components of the assessment. Ongoing clinical assessment of health and body condition will gauge the need for reasses...
Brommer H, Sloet van Oldruitenborgh-Oosterbaan MM, Kessels B.Reference values for haematological and blood biochemical variables may vary per breed and are influenced by age and, to a certain extent, by rearing conditions. To investigate the influence of age and rearing conditions, these variables were measured in Dutch Warmblood foals from birth to 5 months of age. The foals were divided into three groups with different exercise regimens: 14 foals got boxrest with no exercise; 14 foals were kept in comparable boxes, but received daily exercise; and 15 foals were maintained on pasture with free exercise. Blood samples were collected each month and 36 ha...
Macon EL, Harris P, Barker VD, Adams AA.Seasonal effects on the oral sugar test (OST), used to monitor insulin dysregulation (ID) status to help reduce laminitis risk, are poorly understood in the ID horse. Resting, (basal) insulin (T0) and 60-minute (T60) OST (0.15 mL/Kg BW Karo Light Corn Syrup) insulin responses were evaluated, once per each season over 2 years, in ID (n = 11 14.9 ± 4.3 years; mean ± SD) and non-insulin dysregulated (NID: n = 11 16.4 ± 5.3 years; mean ± SD) horses housed on the same farm. Seasonal morphometric measurements were collected: bodyweight (BW), body-condition scores (BCS), and cresty neck score...
Marley SE, Hutchens DE, Reinemeyer CR, Holste JE, Paul AJ, Rehbein S.Modern anthelmintic use in horses has decreased the prevalence of the large strongyles, which has in turn shifted the focus of parasitologists to the pathogenic importance of the small strongyles, tapeworms, and other parasites. These studies show that a combination product containing ivermectin and praziquantel allowed efficacious treatment of horses for nematode, cestode, and bot infections. The use of this combination product may be of special benefit to horses that are mainly kept outdoors and on grazing pastures.
Lyons ET, Tolliver SC, Collins SS, Drudge JH.Research carried out during the last 4 years (1996-1999) of an 11-year study of the prevalence of internal parasites naturally transmitted to horse foals born on the same pasture on a farm in central Kentucky is presented here. Horses in this herd were not treated with any antiparasitic compound for over 20 years except for a replacement stallion in 1994. A total of 22 species, including 12 species of small strongyles, were recovered in the 4-year period. Transmission patterns of all species (n=35) of endoparasites recovered are compared for the 11-year study. Some of the changes were an incre...
Brunner J, Wichert B, Burger D, von Peinen K, Liesegang A.This study aims at the comparison of the actual feeding of horses with the recommendations from the literature, and it studies the effects of feeding and exercise on several blood metabolic parameters before and after exercise. Blood samples were collected from 25 horses during one-star eventing competitions and evaluated for blood glucose, insulin, lactate, free fatty acids and triglyceride levels. Questionnaires on the feeding practices of the horses were evaluated. The questionnaires revealed that during training, and on tournament days, horses received on average 4.3 kg of concentrate per ...
Mair TS.The clinical features of 18 cases of summer pasture associated obstructive pulmonary disease were reviewed. The horses had signs of obstructive pulmonary disease (expiratory dyspnoea, wheezing and crackling lung sounds and coughing) during the spring, summer or autumn while they were kept permanently at grass with no access to hay or straw, for at least two consecutive years. In nine cases there was a seasonal incidence with the disease occurring during April and May. Eleven of the horses were affected by bouts of severe dyspnoea. Eleven of the horses also suffered from chronic obstructive pul...
Monfort SL, Arthur NP, Wildt DE.Immunoreactive urinary oestrogen conjugates were assessed in daily urine samples (approximately 5 samples/week) collected from 8 Przewalski's mares maintained under semi-free-ranging pasture conditions. The relative percentage contributions of immunoreactive urinary oestrogens during different reproductive stages (oestrus, luteal phase, early, mid- and late gestation) were determined using high-pressure liquid chromatography. In general, conjugated forms of oestrone (oestrone sulphate and oestrone glucuronide) were the major excreted immunoreactive oestrogens in nonpregnant and pregnant Przewa...
McCarthy HE, French NP, Edwards GB, Miller K, Proudman CJ.Equine grass sickness (EGS) occurs repeatedly on certain premises over time. Few studies have sought, or identified, the determinants of this phenomenon in order to inform advice on disease prevention strategies. Objective: Premises-level risk factors are important determinants of whether EGS occurs. Methods: A matched case-control study was undertaken. Sixty premises giving rise to one or more histologically confirmed case of EGS and 120 time-matched control premises were sampled. Data were collected on pasture management, soil nutrient content, pasture nutrient content and local weather cond...
Hansen S, Klintoe K, Austevoll M, Baptiste KE, Fjeldborg J.Icelandic horses are often stabled in loose-housing systems, and to date this type of stabling has not been evaluated with regard to its potential impact on respiratory health. The objective was to assess if differences in management systems (eg, conventional stable, loose housing and pasture only) affect the degree of airway inflammation, evaluated by cytology of tracheal aspirate (TA) and bronchoalveolar lavage (BAL) fluid. In total, 84 Icelandic horses (aged 8.1±4.6 years) housed under three different management systems (conventional stables [n=29], loose-house systems [n=29] and pasture [...
Brown-Douglas CG, Parkinson TJ, Firth EC, Fennessy PF.To examine the growth of spring- and autumn-born Thoroughbred foals raised on pasture. Methods: Bodyweight and growth rates were measured in pasture-raised Thoroughbred horses, born in either spring (n=56) or autumn (n=7), from birth to approximately 13 and 17 months of age. Results: Birthweight tended to be lower in autumn- than spring-born foals (54.4, SD 7.92 kg vs 57.3, SD 5.90 kg; p=0.08). Between birth and 6 months of age, there was no difference in growth rate at equivalent ages between horses born in spring and autumn. Spring-born horses, which were weaned in the autumn, had lower post...
Bairden K, Brown SR, McGoldrick J, Parker LD, Talty PJ.The efficacy of moxidectin 2 per cent equine gel against naturally acquired strongyle infections was assessed in 18 ponies which had grazed on contaminated pasture before being housed for eight weeks. Twenty-four hours before the treatment, two randomly selected ponies were euthanased and their worm burdens were determined. Eight of the remaining 16 ponies were treated with moxidectin 2 per cent gel while the other eight were given a placebo gel. Eight weeks later the 16 animals were necropsied and their worm burdens established. A 100 per cent efficacy was recorded against adult and lumenal L...
Kenny LB, Ward D, Robson MG, Williams CA.Many methods exist for estimating species composition, but few studies compare those useful in improved horse pastures. The objective of this study was to examine 4 techniques for estimating desirable forage species composition in 2 cool-season horse pastures based on prevalence estimates, repeatability, bias, and practicality, and to select a method for use in a subsequent grazing study. The techniques included Equine Pasture Evaluation Disc (EPED), Line-Point Intercept with 3 transects of 50 observations each (LPI 3-50), LPI with 5 transects of 30 observations each (LPI 5-30), and Step Point...
Kurvers CM, van Weeren PR, Rogers CW, van Dierendonck MC.To describe spontaneous locomotion activity of foals kept under various management conditions and assess the suitability of global positioning system (GPS) technology for recording foal activity. Animals-59 foals. Methods: During the foals' first 4 months of life, 921 observation periods (15 minutes each) were collected and analyzed for locomotion activities. The GPS system was evaluated by simultaneously carrying out field observations with a handheld computer. Results: Foals spent 0.5% of total observed time cantering, 0.2% trotting, 10.7% walking, 32.0% grazing, 34.8% standing, and 21.6% ly...
McGorum BC, Fry SC, Wallace G, Coenen K, Robb J, Williamson G, Aruoma OI.To investigate the etiology of equine dysautonomia (ED), a degenerative polyneuropathy affecting grazing horses, the biochemical composition and antioxidant/prooxidant activities of aqueous extracts of plants collected from ED pastures were determined. Plants collected immediately after an outbreak of ED had reduced antioxidant and weak prooxidant activities when compared with control plants (plants collected from ED pastures out of ED season and control plants from ED pastures that were grown under favorable conditions). ED plants also had significantly increased concentrations of fructose an...
Silva CJFL, Trindade KLG, Cruz RKS, Manso HECCC, Coelho CS, Filho JDR, Nogueira CEW, Aragona F, Fazio F, Manso Filho HC.Erosions and gastric ulcers may be present in horses at any age and under different conditions of rearing and handling. In tropical regions, horses can feed on fruits rich in soluble carbohydrates, such as mangoes, but little is known about how these foods interact with their digestive systems. To test the hypothesis that the ingestion of ripe mangoes with peels could cause disturbances in the digestive processes of horses, an experiment was developed to monitor animals that had free access to ripe mangoes in their pasture areas. Horses (purebred Arabians, n = 5; ~340 kg, ~13 years) were evalu...
Kirschvink N, Di Silvestro F, Sbaï I, Vandenput S, Art T, Roberts C, Lekeux P.This study aimed to test whether shredded cardboard is an appropriate minimum-dust bedding material for heaves-affected horses. Results of standardized in vitro measurement of airborne dust and aeroallergen concentrations of cardboard bedding were significantly lower than those of common bedding materials. Six heaves-affected horses in clinical remission after pasturing were stabled for two months on cardboard bedding and fed grass silage. Pulmonary function tests (PFT: ventilatory mechanics, arterial blood gases, airway inflammation scoring, bronchoalveolar cytology) were performed before, du...
Saastamoinen M, Särkijärvi S, Valtonen E.The main horse phosphorus excretion pathway is through the dung. Phosphorus originating from animal dung and manure has harmful environmental effects on waters. The number of horses has increased in many countries, and several studies have pointed that leaching of P from horse paddocks and pastures are hotspots for high P leaching losses. The hypothesis was that feeding regimes might influence phosphorus digestibility and excretion in feces, and therefore the environmental impact of horse husbandry. A digestibility experiment was conducted with six horses fed six forage-based diets to study ph...
Irby LR, Norland JE, Westfall JA, Sullivan MA.We developed a forage allocation model using a deterministic, linear optimization module in a commercially available spreadsheet package to help resource managers in Theodore Roosevelt National Park (TRNP), North Dakota determine optimum numbers of four ungulate species, bison (Bison bison), elk (Cervus elaphus), mule deer (Odocoileus hemionus), and feral horses, in the Park. TRNP staff actively managed bison, elk, and feral horse numbers within bounds suggested by our model from 1983 to 1996. During this period, we measured vegetation at 8 grassland and 12 wooded sites at 1-3 year intervals t...
Craig TM, Bowen JM, Ludwig KG.After foaling, 6 mares and their foals were placed on equine parasite-free pastures. Observations of fecal nematode eggs and pasture larvae indicated peak cyathostome egg production occurred in late August and early September, with greatest numbers of larvae on the forage appearing during October. Two foals were necropsied for parasitologic evaluations at approximately 155 days of age. Both had approximately 100,000 adult cyathostomes, mostly Cylicostephanus longibursatus, Cylicocyclus nassatus and Cyathostomum catinatum. However, there were nearly 7 times more cyathostome larvae (189,004) in ...
Bockisch F, Aboling S, Coenen M, Vervuert I.Vitamin-D intoxication by yellow oat grass is often reported under the syndrome of enzootic calcinosis in ruminants in the upper regions of the Alps. The intake of Trisetum flavescens in ruminants and horses induces calcification of soft tissue, including vessels, tendons and ligaments, lung, heart and kidneys. Clinical symptoms, including a reluctance to move, inappetence, body-weight loss and impaired organ function, are frequently observed. To date, there are only a very few case reports about yellow-oat-grass intoxication in horses. The present case report describes Vitamin-D intoxication ...
Fernández AS, Larsen M, Nansen P, Grønvold J, Henriksen SA, Wolstrup J.A plot experiment was conducted to investigate the ability of the nematode-trapping fungus Duddingtonia flagrans to reduce the transmission of infective horse strongyle larvae from deposited dung onto surrounding herbage. At three different times during the summer 1995, three groups of horses, naturally infected with large and small strongyles, were fed different doses of D. flagrans spores, while a fourth group of animals served as non-fungal controls. Faeces from all four groups of horses were deposited as artificial dung pats on a parasite-free pasture. Every second week for 8 weeks after d...
Tavela Ade O, Araújo JV, Braga FR, Silva AR, Carvalho RO, Araujo JM, Ferreira SR, Carvalho GR.Horses are hosts to a wide variety of helminthes; the most important are the cyathostomin, or small strongyles. The viability of a fungal formulation (pellets) using the nematode-trapping fungus Monacrosporium thaumasium was assessed in biological control of horse cyathostomin. Two groups (fungus-treated and control) consisted of six mares in each group, crossbred (ages of 2.5 and 3.5 years), were placed in pastures of Cynodon sp. naturally infected with horse cyathostomin larvae. In the treated group, each animal received 1g/10 kg body weight (0.2g/10 kg live weight of fungus) of pellets of s...
Lyn Macon E, Harris P, Partridge E, Day Barker V, Adams A.The oral sugar test (OST) is frequently used to identify insulin dysregulated (ID) equines. The effect of fasting and varying sugar dose for the OST has been investigated in the pony but little work has been done in the horse. This study aimed to investigate (1) an OST response with access to forage continued until the time of the OST or prevented for 3 hours prior to the OST and (2) responses of ID and non-insulin dysregulated (NID) horses to two different OST doses. Twenty-one mixed-breed horses (14.8 ± 3.2 years; 574.3 ± 83.3 kg) were used in two randomized crossover studies. Seven ID and...
Shingu Y, Kondo S, Hata H.In this study, grazing behavior of mares and cows was compared on woodland pastures, in the context of foraging hierarchy. A horse-group (12 native Hokkaido horses) and a cattle-group (5 Hereford cows) were grazed on the woodland pastures of 13.3 ha and 5.8 ha, respectively. They grazed mainly on Sasa nipponica. Grazing behavior at a feeding station (FS) scale was recorded for three focal animals in each group. Mares took one bite per FS at a high percentage of FSs (24.3%) and cows took one, two and three bites per FS at high percentage (20.3%, 19.2% and 15.4%, respectively). Although feeding ...
Zeyner A, Bessert J, Gropp JM.Our hypothesis was that, because horses have not evolved as fat eaters, there may be negative metabolic long-term effects of feeding a high fat diet. The objective of the present study was to identify these long-term effects and compare them with the effects of isoenergetic long-term high starch feeding. This randomised block study with 20 exercised horses looked at the effect of feeding either a high starch (HS) or a high fat (HF) diet type in 3 periods during stabling (Stable 1), pasture, and stabling (Stable 2) over 390 days. The horses received a HS or HF concentrate, straw, hay and 6 h pa...
Ladefoged O, Stürup S.A case of copper deficiency or molybdenum toxicosis in cattle, sheep and horses after heavy pollution of a pasture with fly ash is described. If the pastures had not been grazed by cattle and sheep as well as the horses, it would have been difficult to identify the reason for the intoxication in the horses. It is argued that molybdenum intoxication, although seldom seen in non-ruminants, was the cause of the deaths of the horses. It is suggested that the bioavailability of molybdenum in fly ash is high and therefore can cause equine intoxication.
