"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Baccarin RY, Pereira MA, Roncati NV, Bergamaschi RR, Hagen SC.This study aimed to detect, by radiographic examination, the evolution of osteochondral lesions in the tarsocrural and femoropatellar joints of Lusitano foals. Within 1 month of age, 76.08% of foals had radiographic signs of osteochondrosis, but only 16.20% had lesions at 18 months. The radiographic signs resolved by 5 mo of age in most foals, but some cases that involved either joint, were not resolved until 12 mo of age. It is thought that the "age of no return" is 5 mo for the tarsocrural and 8 mo for the femoropatellar joint but this study demonstrated regression of osteochondral lesions i...
Carstens A, Kirberger RM, Velleman M, Dahlberg LE, Fletcher L, Lammentausta E.Osteoarthritis of the metacarpo/metatarsophalangeal joints is one of the major causes of poor performance in horses. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) may be a useful technique for noninvasively quantifying articular cartilage damage in horses. The purpose of this study was to describe dGEMRIC characteristics of the distal metacarpus3/metatarsus3 (Mc3/Mt3) articular cartilage in 20 cadaver specimens collected from normal Thoroughbred horses. For each specimen, T1 relaxation time was measured from scans acquired precontrast and at 30, 60, 120, and 180...
Montgomery JB, Wichtel JJ, Wichtel MG, McNiven MA, McClure JT, Markham F, Horohov DW.The effects of selenium (Se) supplementation and source on equine immune function have not been extensively studied. This study examined the effects of oral Se supplementation and Se source on aspects of innate and adaptive immunity in horses. Fifteen horses were assigned to 1 of 3 groups (5 horses/group): control, inorganic Se (sodium selenite), organic Se (Se yeast). Immune function tests performed included: lymphocyte proliferation in response to mitogen concanavalin A, neutrophil phagocytosis, antibody production after rabies vaccination, relative cytokine gene expression in stimulated lym...
Capolongo F, Gallina G, Fidani M, Baia F, Montesissa C.This study investigated whether a single intra-articular administration (IA) of dexamethasone (DEX) in horses at therapeutic dosage could exert a systemic effect by influencing the hypothalamic-pituitary-adrenal axis activity as a consequence of (limited) absorption and systemic distribution. The results indicated that DEX was detectable in urine collected 12-48 h after IA administration and that injection was accompanied by a reduced urine excretion of cortisol, 6β-hydroxycortisol (6βOHF) and two other metabolites of cortisol lasting up to 48 h post-DEX administration. The systemic effect...
Goren G, Fritz J, Dillitzer N, Hipp B, Kienzle E.Hay stabilises urine pH in horses. It is unknown whether this is an effect of structure or of chemical composition. In this study, four ponies (230-384 kg body weight [BW]) were fed six different diets with either a structure or a composition similar to hay with and without acidifiers in a cross-over experimental design in amounts to maintain body weight with the following main compounds: Fresh grass (GRASS), alfalfa hay (ALF), grass cobs (COBS), grass silage (SIL), straw (STR) or extruded straw (STRe) for 2 to 10 days. Urine pH was measured in all trials, blood pH, blood base excess and bicar...
Crişan MI, Damian A, Gal A, Miclăuş V, Cernea CL, Denoix JM.The purpose of this study was to provide a detailed description of the vascular changes in the distal part of deep digital flexor tendon (DDFT). Eight isolated forelimbs were collected from 8 horses with DDF tendinopathy diagnosed post-mortem by ultrasound and gross anatomopathological examination. The samples were fixed in 10% neutral buffered formalin, softened in 4% phenol and dehydrated with ethylic alcohol. Goldner's Trichrome staining method was used. The histopathological examination revealed vascular proliferation associated with structural disorders of blood vessels. Angiogenesis, fib...
Ros-García A, M'ghirbi Y, Hurtado A, Bouattour A.The genetic diversity and prevalence of Babesia and Theileria species in the equine population of Tunisia were studied using reverse line blot (RLB) hybridization on blood samples and unfed adult ticks collected from apparently healthy horses from three bioclimatic zones in Tunisia. Piroplasms were identified in 13 of 104 of the horse blood samples analyzed (12.5%) and five genotype groups were identified: Theileria equi group A (nine animals, 8.7%), group C (one animal, 1.0%) and group D (three animals, 2.9%), and Babesia caballi groups A and B (one animal each). All horses from the semi-arid...
Williams LB, Pinard CL.Corneal ulceration is commonly diagnosed by equine veterinarians. A complete ophthalmic examination as well as fluorescein staining, corneal cytology, and corneal bacterial (aerobic) and fungal culture and sensitivity testing are necessary for all infected corneal ulcers. Appropriate topical antibiotics, topical atropine, and systemic NSAIDs are indicated for all corneal ulcers. If keratomalacia (melting) is observed, anticollagenase/antiprotease therapy, such as autologous serum, is indicated. If fungal infection is suspected, antifungal therapy is a necessity. Subpalpebral lavage systems all...
Burba DJ.Managing traumatic foot wounds in horses may require surgical intervention. These wounds include coronary-band and heel-bulb lacerations, septic pedal osteitis, septic navicular bursitis, sepsis of the collateral cartilages, and hoof-wall injuries. This article provides a practical overview of the surgical management of these types of wounds.
Wang L, Luo DK, Pan ZY.The aim of the present study was to investigate the association between glucocorticoid receptors and steroid‑induced avascular necrosis of the femoral head (SANFH). Healthy New Zealand rabbits were randomly divided into 3 groups (n=16/group); the normal (no treatment), control (horse serum injections) and treatment (horse serum and methylprednisolone injections) groups. Methylprednisolone and horse serum injections were used to establish a SANFH model in rabbits; magnetic resonance imaging (MRI) and histopathological analysis were used to evaluate the SANFH rabbit model. Total cholesterol an...
Nieto JE, Maher O, Stanley SD, Knych HK, Snyder JR.To determine the pharmacokinetics, pharmacodynamics, and safety of zoledronic acid in horses. Methods: 8 healthy horses. Methods: A single dose of zoledronic acid (0.057 mg/kg, IV) was administered during a 30-minute period. Venous blood was collected at several time points. Zoledronic acid concentration in plasma was measured by liquid chromatography-tandem mass spectrometry, and pertinent pharmacokinetic parameters were determined. Plasma was analyzed for total calcium, BUN, and creatinine concentrations and a marker for bone resorption (C-terminal telopeptides of type I collagen). Results: ...
Zeyner A, Romanowski K, Vernunft A, Harris P, Kienzle E.Based on a series of exercise tests which included the estimation of sweat losses, this article proposes a novel sweat scoring system for exercising horses. This provides a practical estimate of individual animal exercise-induced sweat losses, based on visible appearance of sweat on the coat after work, which takes into account the effect of various influencing factors. In terms of accuracy and flexibility, the score seems to provide advantages over estimates based on current general recommendations from reference books. Additional studies are needed to validate this scoring system and its use...
Kim W, McArdle BH, Kawcak CE, McIlwraith CW, Firth EC, Broom ND.To investigate histomorphometric changes in the cartilage and subchondral bone of the third carpal bone associated with conditioning exercise in young Thoroughbreds. Methods: Nine 18-month-old Thoroughbreds. Procedures-Both third carpal bones of 9 horses (4 exercised spontaneously at pasture only and 5 given additional conditioning exercise beginning at a mean age of 3 weeks) were evaluated. Histomorphometric variables (hyaline and calcified cartilage thickness and collagen orientation; vascular channel area, number, and orientation; and osteochondral junction rugosity) of the third carpal bon...
Nieto JE, Morales B, Yamout SZ, Stanley SD, Harmon FA, Snyder JR.To determine the response to neostigmine of the contractile activity of the jejunum and pelvic flexure and the effects of a continuous rate infusion (CRI) of neostigmine in horses. Methods: 7 adult horses and tissue from 12 adult horses. Methods: A CRI of neostigmine (0.008 mg/kg/h) or placebo was administered to 6 horses in a crossover study design. Gastric emptying was evaluated by the acetaminophen test. The frequency of defecation and urination and the consistency and weight of feces were recorded throughout the experiment. The effect of neostigmine on smooth muscle contractile activity wa...
Kitaoka Y, Endo Y, Mukai K, Aida H, Hiraga A, Takemasa T, Hatta H.To evaluate the effects of a single incremental exercise test (IET) on mRNA expression and protein content of monocarboxylate transporter (MCT) 1 and MCT4 in the gluteus medius muscle of Thoroughbreds. Methods: 12 Thoroughbreds (6 males and 6 females; age, 3 to 4 years). Methods: Horses underwent an IET before and after 18 weeks of high-intensity exercise training (HIT). Horses were exercised at 90% of maximal oxygen consumption for 3 minutes during the initial 10 weeks of HIT and 110% of maximal oxygen consumption for 3 minutes during the last 8 weeks of HIT. Gluteus medius muscle biopsy spec...
Blatter M, Haase B, Gerber V, Poncet PA, Leeb T, Rieder S, Henke D, Janett F, Burger D.In April 2008 a Franches-Montagnes colt was born with an unusual coat colour phenotype which had never been observed in that population before. The foal showed extended white markings on body and legs, a white head and blue eyes. As both parents have an unremarkable bay coat colour phenotype, a de novo mutation was expected in the offspring and a candidate gene approach revealed a spontaneous mutation in the microphthalmia associated transcription factor gene (MITF). A detailed clinical examination in 2010 indicated an impaired hearing capacity. As in the American Paint Horse large white facia...
Caron JP.Laparoscopic removal of the gonads from male and female horses is regularly performed for a variety of reasons. In female horses, common indications for ovariectomy include behavioral problems and signs of abdominal pain that are linked to estrus. Another indication is an abnormal, enlarged ovary, typically due to ovarian neoplasia, the most common being granulosa thecal cell tumor. Ovariectomy is also a treatment option for ovarian hematomas and other abnormalities. In addition, ovariectomy is used to sterilize mares intended for artificial insemination or embryo transfer programs.
Musilova P, Kubickova S, Vahala J, Rubes J.Equidae is a small family which comprises horses, African and Asiatic asses, and zebras. Despite equids having diverged quite recently, their karyotypes underwent rapid evolution which resulted in extensive differences among chromosome complements in respective species. Comparative mapping using whole-chromosome painting probes delineated genome-wide chromosome homologies among extant equids, enabling us to trace chromosome rearrangements that occurred during evolution. In the present study, we performed subchromosomal comparative mapping among seven Equidae species, representing the whole fam...
Todhunter KH, Muscatello G, Blishen AJ, Chicken C, Perkins NR, Gilkerson JR, Begg AP.A series of unusual abortions occurred in Thoroughbred and Quarterhorse mares in the Hunter Valley region of New South Wales from mid-March to November 2004. The initial link between early cases was the microbiological culture of atypical environmental coryneforms from the stomach contents and/or lungs of fetuses aborted on different properties. Methods: The unique pathologic lesions were described with a case definition and the term 'equine amnionitis and fetal loss' (EAFL) was established. Results: The causal factor was the ingestion of the processionary caterpillar (Ochrogaster lunifer). Ba...
Silva MG, Graça T, Suarez CE, Knowles DP.Theileriosis in horses and cattle is caused by tick-borne Apicomplexa parasites and results in death or life-long infection in their respective hosts. Transmission risk associated with persistent infection severely limits movement of horses and cattle resulting in economic losses. The recent reemergence of Theileria equi infection in U.S. horses demonstrates the continual threat Apicomplexa parasites represent to global animal health. A paucity of data concerning equine immune responses to T. equi, including antigens recognized by antibodies in clinically asymptomatic, persistently infected ho...
Newman JC, Prange T, Jennings S, Barlow BM, Davis JL.The objectives of this study were to examine the pharmacokinetics of tobramycin in the horse following intravenous (IV), intramuscular (IM), and intra-articular (IA) administration. Six mares received 4 mg/kg tobramycin IV, IM, and IV with concurrent IA administration (IV+IA) in a randomized 3-way crossover design. A washout period of at least 7 days was allotted between experiments. After IV administration, the volume of distribution, clearance, and half-life were 0.18 ± 0.04 L/kg, 1.18 ± 0.32 mL·kg/min, and 4.61 ± 1.10 h, respectively. Concurrent IA administration could not be...
Al-Haidar A, Farnir F, Deleuze S, Sandersen CF, Leroux AA, Borde L, Cerri S, Amory H.Little is known about the effect of various animal's signalment variables on echocardiographic reference values in the equine species. This study was performed to evaluate the effect of sex, breed, age and body weight (BW) on echocardiographic measurements in the equine species. Echocardiography was performed on 212 ponies or horses of various breeds, aged from 1 day to 37 years old (mean±SD: 7.8 ± 5.8 years), BW 38-890 kg (mean ± SD: 421 ± 133 kg), and free of cardiac disease. Fifty of those animals aged from 2 months to 35 years old (mean ± SD: 11.6 ± 6.4 years old); BW 77-662 kg (mean...
Mavadiya SV, Raval SK, Mehta SA, Kanani AN, Vagh AA, Tank PH, Patel PR.A highly contagious virus infection in horses, influenza is the single most important equine respiratory disease in the world. This paper presents details of a one-year study (1 June 2008 to 31 May 2009) to determine the prevalence of equine influenza in the horses of Gujarat State in India. The prevalence of equine influenza A/equi-2 was 12.02%, but none of the samples were positive for equine influenza A/equi-1. The prevalence of equine influenza (A/equi-2) was 15.38%, 11.94%, 10.18%, and 9.09% in horses of the Kathiyawari breed, a non-descript breed, the Marwari breed and the Indian Thoroug...
Armengou L, Jose-Cunilleras E, Ríos J, Cesarini C, Viu J, Monreal L.Sick neonatal foals suffer from a variety of endocrine and metabolic derangements that may be related to outcome. There are several hepatic and lipid metabolism blood markers that have never been assessed in neonatal foals. Objective: Assess panel of endocrine and metabolic variables in group of sick and healthy neonatal foals in order to describe their relationship with diagnosis and survival. Methods: All neonatal foals referred to Unitat Equina-Fundació Hospital Clínic Veterinari during 3 consecutive foaling seasons and a group of healthy foals. Methods: Observational prospective study. B...
Lindahl S, Båverud V, Egenvall A, Aspán A, Pringle J.Strangles is a contagious equine-specific disease caused by Streptococcus equi subsp. equi. Unfortunately, detection of S. equi can fail in up to 40% of horses with strangles. Whereas recent molecular biologic methods and sampling techniques have improved recovery of S. equi optimal sampling methods and laboratory analyses remain ill-defined. Objective: To determine the yield of S. equi from horses with acute strangles in confirmed outbreaks by field-sampling methods subjected to culture and biochemical identification, and real-time PCR directly and after culture. Methods: Fifty-seven horses o...
Borer-Weir KE, Menzies-Gow NJ, Bailey SR, Harris PA, Elliott J.A simple, accurate test for identifying individual animals at increased risk of laminitis would aid prevention. Laminitis-prone ponies have a greater serum insulin response to dexamethasone administration than normal ponies in the summer, but the response during different seasons is unknown. Objective: To test the hypothesis that previously laminitic ponies have a greater insulin response to dexamethasone than normal ponies, which is present during all seasons. Methods: Prospective longitudinal study. Methods: Overnight dexamethasone suppression tests were performed on 7 normal ponies and 5 pr...
Spaas JH, Broeckx S, Van de Walle GR, Polettini M.Stem-cell therapy represents a promising strategy for the treatment of challenging pathologies, such as large, infected wounds that are unresponsive to conventional therapies. The present study describes the clinical application of peripheral blood stem cells (PBSCs) for the treatment of four adult Warmblood horses with naturally occurring wounds, which were unresponsive to conventional therapies for at least 3 months. A visual assessment was performed, and a number of wound-healing parameters (granulation tissue, crust formation and scar formation) were evaluated. In all cases, tissue overgro...
Beard LA, Pelzel AM, Rush BR, Wright AM, Galgut BI, Hennager SG, King AO, Traub-Dargatz JL.A 7-year-old Quarter Horse gelding used for unsanctioned racing was examined because of fever and anorexia. Results: Physical examination revealed fever, tachycardia, and tachypnea. Results of a CBC indicated anemia and mild thrombocytopenia. Results of microscopic examination of a blood smear indicated piroplasms in erythrocytes, consistent with Babesia spp. Regulatory authorities were contacted, and results of serologic testing at the National Veterinary Services Laboratories confirmed acute Babesia equi infection. Results: Equids on the home premises of the index horse were placed under qua...
Port CD, Ketels KV, Coffin DL, Kane P.Normal lung architecture of the rat, mouse, hamster, horse, and human was compared to that of emphysematous lungs from the same species by utilizing a light microscope and a scanning electron microscope (SEM). The results obtained by SEM examination of normal and emphysematous lungs corresponded to those obtained with the light microscope. However, the SEM provided a view of alveoli and airway morphology not obtainable with the light microscope. Because of the variability in pore size and number of pores per alveolus, a pore-to-alveolus ratio was determined with the SEM on the normal lungs of ...
Semevolos SA.This article reviews current knowledge of osteochondritis dissecans (OCD) development in horses, including normal cartilage development, early osteochondrosis pathogenesis, and factors that result in healing or advancement to OCD fragments. Discussion includes current theories, detection, and therapeutic options.
Toishi Y, Tsunoda N, Kirisawa R.Equine coital exanthema (ECE) has been reported in many countries, but equine herpesvirus 3 (EHV-3) has been isolated only once in Japan. In 2015, symptoms of ECE were found, and EHV-3 was isolated in two stallions. Valacyclovir, an anti-herpesvirus agent, was administered orally. The stallions rested from mating for more than two weeks, causing enormous financial losses because of their high fees. This is the first study in which valacyclovir was administered for ECE. Though valacyclovir treatment did not shorten the duration of healing, the affected area did not expand after administration o...
Machtinger ET, Geden CJ, Hogsette JA, Leppla NC.House flies, Musca domestica L., and stable flies, Stomoxys calcitrans (L.), (Diptera: Muscidae), common pests on equine facilities, were studied in the laboratory to determine the success and duration of larval development and oviposition preferences on six substrates commonly found on equine facilities. Substrates tested were hay soiled with urine and manure, fresh horse manure, pine shaving bedding soiled with urine and manure (72 h in a manure pile), builders sand bedding soiled with urine and manure aged 3 d, and soil from an overgrazed pasture mixed with urine and manure of variable age....
Oliver LJ, Baird DK, Baird AN, Moore GE.To characterise the prevalence and distribution of radiographic changes in the hocks and stifles of Thoroughbred yearling colts and fillies in New Zealand and compare them with other populations of young horses. Methods: Repository radiographs taken in New Zealand for the 2003-2006 Thoroughbred national yearling sales were evaluated by two individual readers. The distribution of radiographic changes was classified as left side only, right side only, or bilateral. Lesions were categorised by type, location, and sex of the yearling. Complete sets of hock and stifle radiographs of 1,505 yearlings...
Aleman M, Holliday TA, Nieto JE, Williams DC.Brainstem auditory evoked response has been an underused diagnostic modality in horses as evidenced by few reports on the subject. Objective: To describe BAER findings, common clinical signs, and causes of hearing loss in adult horses. Methods: Study group, 76 horses; control group, 8 horses. Methods: Retrospective. BAER records from the Clinical Neurophysiology Laboratory were reviewed from the years of 1982 to 2013. Peak latencies, amplitudes, and interpeak intervals were measured when visible. Horses were grouped under disease categories. Descriptive statistics and a posthoc Bonferroni test...
Saville WJ, Dubey JP, Oglesbee MJ, Sofaly CD, Marsh AE, Elitsur E, Vianna MC, Lindsay DS, Reed SM.Sarcocystis neurona and Sarcocystis fayeri infections are common in horses in the Americas. Their antemortem diagnosis is important because the former causes a neurological disorder in horses, whereas the latter is considered nonpathogenic. There is a concern that equine antibodies to S. fayeri might react with S. neurona antigens in diagnostic tests. In this study, 4 ponies without demonstrable serum antibodies to S. neurona by Western immunoblot were used. Three ponies were fed 1 x 10(5) to 1 x 10(7) sporocysts of S. fayeri obtained from dogs that were fed naturally infected horse muscles. A...
Hay MF, Allen WR.Gonadal tissue obtained at about 50-day intervals from Days 60 to 300 of gestation was examined histologically, histochemically and in the electron microscope. The marked enlargement of the gonads (ovaries or testes) reached a peak around Day 250 and was caused by hypertrophy and hypoplasia of interstitial cells. These cells had all the ultrastructural characteristics of a steroid-secreting cell but delta5-3beta-hydroxysteroid dehydrogenase (3beta-HSD) was not detected at any stage of their development. There was no significant change in the ultrastructure of the interstitial cells between Day...
Allen WR, Urwin V, Simpson DJ, Greenwood RE, Crowhurst RC, Ellis DR, Ricketts SW, Hunt MD, Digby NJ.Daily oral administration of 30 mg allyl trenbolone (Regumate) for 10 to 15 days to 61 barren, maiden and lactating Thoroughbred mares which were exhibiting either deep anoestrus, shallow anoestrus, prolonged spring oestrus or lactation anoestrus, resulted in 54 mares (88 per cent) showing oestrous behaviour within 8 days, and 51 mares (84 per cent) ovulating within 18 days, after the last dose of compound. Response rate was lowest in mares in deep anoestrus. Of the 38 Regumate-treated mares which were covered during the induced oestrus, 21 (55 per cent) conceived. The practical value of this ...
Sentsui H, Kono Y.Horse erythrocytes treated with equine infectious anemia virus hemagglutinin were phagocytized by cultivated horse leukocytes (mainly macrophage-like cells and partly polymorphonuclear cells) after incubation with fresh horse serum but not with inactivated horse serum. The phagocytosis began as soon as the erythrocytes were added to the leukocyte cultures, and the majority of the reaction proceeded within 30 minutes. Addition of antiserum showed a slightly suppressing but no enhancing effect on the phagocytosis. Phagocytosis seemed to be caused by the recognition of the third complement compon...
Perkins GA, Nydam DV, Flaminio MJ, Ainsworth DM.The purposes of this study were to (1) prospectively establish serum IgM and IgG concentrations in normal, fit, adult horses over time and (2) determine the accuracy of serum IgM concentrations for diagnosing lymphoma. Serial IgM and IgG concentrations were measured with a radial immunodiffusion assay in 25 regularly exercised horses at 6-week intervals. Horses had serum IgM concentrations ranging from 50 to 242 mg/dL over 5 months, with 20% of horses having IgM < or = 60 mg/dL. The normal range for IgM in fit horses should be considered 103 +/- 40 mg/dL and a cut-point for an IgM deficiency, ...
Schvartz G, Tirosh-Levy S, Barnum S, David D, Sol A, Pusterla N, Steinman A.Equine coronavirus (ECoV) infection is the cause of an emerging enteric disease of adult horses. Outbreaks have been reported in the USA, EU and Japan, as well as sporadic cases in the UK and Saudi Arabia. Infection of ECoV in horses in Israel has never been reported, and the risk of exposure is unknown. Importation and exportation of horses from and into Israel may have increased the exposure of horses in Israel to ECoV. While the disease is mostly self-limiting, with or without supportive treatment, severe complications may occur in some animals, and healthy carriers may pose a risk of infec...
Raisis AL.This review aims at evaluating studies investigating the effects of anaesthesia on skeletal muscle blood flow and associated cardiovascular function in anaesthetized horses and discusses how the results of these studies contribute to our understanding of the pathogenesis and prevention of post-anaesthetic myopathy. Methods: Pubmed & personal files. Conclusions: There is little published information on the effects of anaesthesia on skeletal muscle blood flow in horses. Available reports predominantly refer to halothane and isoflurane. The effects of vasoactive drugs have mainly been studied...
Hewes CA, Keoughan GC, Gutierrez-Nibeyro S.Enucleation was performed in 5 horses under local anesthesia and sedation with the horse standing. Minimal hemorrhage occurred during the surgical procedure, and there were no other reported complications. Standing enucleation is a surgery that is safe to perform in horses. L’énucléation a été réalisée chez 5 chevaux en position debout sous anesthésie locale et sédation. Une hémorragie minime est survenue pendant la procédure chirurgicale et il n’y a pas eu de complications rapportées. L’énucléation debout est une chirurgie sécuritaire chez le cheval. (Traduit par Docteur ...
Timoney PJ, Powell DG.Between January 1978 and August 1982 the streptomycin resistant strain of the contagious equine metritis organism (CEMO) was isolated from 15 colts and two fillies in the United Kingdom and Ireland. A first season stallion was also suspected of having initiated an outbreak of contagious equine metritis (CEM) at the beginning of the 1982 breeding season. A detailed investigation of the breeding history of the dams and sires of each positive individual indicated that in a number of cases the CEMO was acquired either in utero or following transmission at the time of parturition. In several other ...
Ing NH, Laughlin AM, Varner DD, Welsh TH, Forrest DW, Blanchard TL, Johnson L.In the testis of the 1.5-year-old horse, spermatogenesis initiates locally in grossly light, central areas that contrast with grossly dark, peripheral areas that are as yet inactive in spermatogenesis. Gene expression was compared between "light" and "dark" tissues of 1.5-year-old horse testes to identify mechanisms important to the initiation of spermatogenesis. Microarrays containing human cDNAs were used to assess expression levels of 9132 genes simultaneously in matched pairs of dark and light testis tissues from 3 prepubertal colts. In all 3 analyses, dysferlin (DYS), down-regulated in ov...
Ribonnet C, Palmers K, Saegerman C, Vanderperren K, van Galen G.Lung ultrasound (LUS) is poorly evaluated in horses, especially perioperatively. Objective: (1) Describe LUS findings in healthy horses before and after general anesthesia (GA), (2) evaluate if GA induces ultrasonographic changes in healthy horses, (3) suggest a LUS scoring system, (4) identify horse variables that are associated to LUS changes after anesthesia. Methods: Twenty-five healthy adult horses undergoing elective surgery. Methods: Prospective hypothesis-driven observational study. LUS findings were recorded before anesthesia, 5 minutes in recovery, 15 minutes, 2H, 3H, 4H, 6H, and ...
Lloyd KC, Stover SM, Pascoe JR, Adams P.Chemical and cytologic effects and bactericidal activity of gentamicin in septic synovial fluid were evaluated in an experimental model of infectious arthritis in horses. Septic arthritis was induced by inoculation of approximately 7.5 X 10(6) colony-forming units of Escherichia coli into 1 antebrachiocarpal joint in each of 16 clinically normal adult horses. Clinical signs of septic arthritis were evident 24 hours after inoculation. Horses were allotted to 3 groups: group-1 horses (n = 5) each were given 150 mg of gentamicin (50 mg/ml; 3 ml) intra-articularly (IA); group-2 horses (n = 5) each...
Bayless RL, Moore AR, Hassel DM, Byer BJ, Landolt GA, Nout-Lomas YS.Detection of equine acute kidney injury (AKI) is hindered by limited markers of early renal damage in horses. N-acetyl-β-D-glucosaminidase (NAG), a lysosomal enzyme in renal tubular epithelium released into urine during tubular insult, has shown promise for early identification of AKI in humans and other species. We validated an assay for NAG in equine urine and measured urinary NAG in 7 azotemic and 7 non-azotemic client-owned adult horses. The enzymatic NAG assay was validated using within- and between-run coefficients of variation (CVs), recovery following standard addition, and linearity ...
Barsotti G, Sgorbini M, Marmorini P, Corazza M.To determine the prevalence and describe ocular abnormalities in healthy Standardbred foals within 48 h of birth. Methods: One hundred and two neonatal foals. Methods: All foals had an unassisted delivery. On the basis of physical examination and the results of hematological and biochemical parameters, all foals were unaffected by systemic diseases. A complete ophthalmic examination was performed within 48 h of birth. Foals with ocular hemorrhages were re-examined weekly until the abnormalities were resolved. Results: 65/102 (63.7%) foals did not show ocular abnormalities, while in 37/102 (36....
Bloom F, Draper S, Bennet E, Marlin D, Williams J.Horse welfare is a priority in the equine sport of endurance riding. Identification and reduction of risk factors associated with elimination and lameness have been the focus of research to date, however, this has centred on international competition. National federations recognise there is a need to consider risk factors for elimination at a more local level. Objective: Determine current risk factors associated with horse eliminations, specifically lameness eliminations within British endurance. Methods: Retrospective cohort study. Methods: Data were extracted from the Endurance GB database, ...
Bermúdez SE, Espinosa JD, Cielo AB, Clavel F, Subía J, Barrios S, Medianero E.We present the results of a study on myiasis in Panama during the first years of a Cochliomyia hominivorax eradication program (1998-2005), with the aim of investigating the behavior of the flies that produce myiasis in animals and human beings. The hosts that registered positive for myiasis were cattle (46.4%), dogs (15.3%), humans (14.7%), birds (12%), pigs (6%), horses (4%), and sheep (1%). Six fly species caused myiasis: Dermatobia hominis (58%), Phaenicia spp. (20%), Cochliomyia macellaria (19%), Chrysomya rufifacies (0.4%), and maggots of unidentified species belonging to the Sarcophagid...
Deschene K, Céleste C, Boerboom D, Theoret CL.As a transient hypoxic state exists within skin wounds in horses and may be important for the healing process, this study sought to identify a molecular hypoxia response occurring in horse limb and body wounds healing by second intention. Hypoxia-inducible factor 1α (HIF1α) protein expression was studied throughout repair by Western blotting and immunofluorescence. Paradoxically, HIF1α was strongly expressed in intact skin and its expression decreased dramatically following wounding (p<0.01), despite the expected hypoxic state within the wounded tissue. HIF1α levels reincreased in parallel...
Lefebvre R, Theoret C, Doré M, Girard C, Laverty S, Vaillancourt D.An 8-year-old Arabian mare was admitted for a large ovarian anovulatory follicle. A clinical diagnosis of ovarian tumor and endometritis was established. Histological examinations revealed an ovarian teratoma and a grade II endometritis. Three months after unilateral ovariectomy, the mare was confirmed pregnant and eventually gave birth uneventfully. Une jument Arabe de 8 ans fut présentée pour un gros ovaire. Un diagnostic de tumeur ovarienne et d’endométrite fut posé. L’examen histologique confirma un tératoma ovarien et une endométrite grade II. Trois mois après une ovariectomie...
Ginther OJ, Utt MD, Bergfelt DR, Beg MA.The interrelationships of progesterone, estradiol, and LH were studied in mares (n=9), beginning at the first ovulation (Day 0) of an interovulatory interval. An increase in mean progesterone concentrations began on Day 0 and reached maximum on Day 6, with luteolysis beginning on Day 14. A common progesterone threshold concentration of about 2 ng/ml for a negative effect on LH occurred at the beginning and end of the luteal phase. Progesterone and LH concentrations decreased at a similar rate from Day 6 until the onset of luteolysis on Day 14, consistent with a decreasing positive effect of LH...
Wang X, Bou G, Zhang X, Tao L, Shen Y, Na R, Liu G, Ren H, Ren X, Song L, Su S, Bai D, Zhao Y, Li B, Dugarjaviin M.Having considered that the current methods are costly and time-consuming, we designed an only 3 pairs primer-based PCR test to accurately identify the species and gender in horses, donkeys, mules and hinnies. Through a thorough sequence comparison between horse and donkey's highly similar genomes, and a vast amount of preliminary confirmation, we found that three fragments, CNGB3 gene on an autosome, displacement loop region on mitochondrial DNA and SRY genes on chromosome Y, within these equine DNA, are enough to enable us achieving our goal. The PCR test described here would be an economical...
Anzai T, Sheoran AS, Kuwamoto Y, Kondo T, Wada R, Inoue T, Timoney JF.Streptococcus equi causes equine strangles. The acute disease has many of the hallmarks of an acute response including high fever, elevated plasma fibrinogen and neutrophilia, affects known to be mediated by proinflammatory cytokines. The objective of this study was to screen-culture supernatants from equine clinical isolates of S. equi and S. zooepidemicus for stimulation of mitogenic responses by horse peripheral blood mononuclear cells. Mitogenicity comparable to that of concanavalin A was detected in culture supernatants of S. equi strains but not in those of S. zooepidemicus. Mitogenicity...
Watts MR, Hegedus OC, Eades SC, Belknap JK, Burns TA.Hyperinsulinemia is associated with equine laminitis, and digital lamellar inflammation in equine metabolic syndrome-associated laminitis (EMSAL) is modest when compared with sepsis-associated laminitis. Objective: To characterize digital lamellar inflammation in horses in a euglycemic-hyperinsulinemic clamp (EHC) model of laminitis. Methods: Sixteen healthy adult Standardbred horses. Methods: Prospective experimental study. Horses underwent EHC or saline infusion (CON) for 48 hours or until the onset of Obel grade 1 laminitis. Horses were euthanized, and digital lamellar tissue was collecte...