"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.
Kearns CF, McKeever KH, Abe T.Locomotion requires skeletal muscle to sustain and generate force. A muscle's force potential is proportional to its weight. Since the larger the muscle the larger its potential power output, a better understanding of the proportion of skeletal muscle a horse possesses may lead to a better understanding of horse performance. Several techniques exist to assess body composition, which include dual energy X-ray absorption, underwater (hydrostatic) weighing, derivation from total body water, bio-electric impedance, air displacement, body condition scoring, cadaver dissection and ultrasound. The re...
Ferrell EA, Gavin PR, Tucker RL, Sellon DC, Hines MT.Magnetic resonance (MR) imaging was used as a neurodiagnostic modality in the assessment of 12 horses with neurologic disease localized cranial to the foramen magnum. This retrospective study included a mixed population of horse breeds and consisted of three foals and nine adult horses. MR sequences of the head and central nervous system of each horse were acquired. Routine MR sequences included transverse T1 weighted (T1wt), T2 weighted (T2wt), and proton density images. Additional imaging sequences were obtained on a patient-dependent basis. Eight neurologic related diseases were diagnosed. ...
Schoenborn WC, Rick MC, Hornof WJ.A 6-year-old Thoroughbred gelding presented with a left forelimb lameness. The results of lameness examination, radiography, nuclear scintigraphy, and computed tomography are presented. Based on the diagnostic imaging, subchondral fractures and osteochondritis dissecans lesions of the proximal articular surface of the proximal phalanx were diagnosed. A brief discussion of osteochondritis dissecans is presented.
Autorino GL, Battisti A, Deubel V, Ferrari G, Forletta R, Giovannini A, Lelli R, Murri S, Scicluna MT.During the late summer of 1998, veterinary authorities in Tuscany, Italy, received reports of cases of neurologic disease among horses residing in a large wetland area located in the provinces of Florence and Pistoia. West Nile virus was isolated from two of the six horses that died or were euthanized. A retrospective epidemiologic study identified 14 clinical neurologic cases that occurred from August 20 to October 6 (attack rate of 2.8%). A serologic survey conducted over a 700-km2 area in stables with and without apparent clinical cases confirmed a wider spread of the infection, with an ove...
Chiaradia E, Gaiti A, Scaringi L, Cornacchione P, Marconi P, Avellini L.To better define the species-specific antioxidant systems and to ascertain the influence of the intracellular redox status on the immune system of different animal species, we determined lymphocyte glutathione peroxidase (GSHPx) activity, plasmatic glutathione levels (GSH) and the effect of H2O2 on the responsiveness of lymphocytes to proliferative stimuli. Among the three species considered, sheep presented the lowest plasmatic GSH and the highest lymphocyte GSHPx activity. On the contrary, dogs showed an inverted pattern (high GSH - low GSHPx). Horses displayed intermediate values for both p...
Squires EL, Carnevale EM, McCue PM, Bruemmer JE.Recent studies demonstrated that zwitterionic buffers could be used for satisfactory storage of equine embryos at 5 degrees C. The success of freezing embryos is dependent upon size and stage of development. Morulae and blastocysts <300 microm can be slowly cooled or vitrified with acceptable pregnancy rates after transfer. The majority of equine embryos are collected from single ovulating mares, as there is no commercially available product for superovulation in equine. However, pituitary extract, rich in FSH, can be used to increase embryo recovery three- to four-fold. Similar to human medic...
Gonçalves S, Julliand V, Leblond A.Many factors have been identified as risk factors for colic in horses in several epidemiological studies. The aim of our paper was to review the results of 12 epidemiological studies, in order to assess the impact of each risk factor for colic. According to the literature, the factors that increase the risk of colic are feeding practices (type and quality of food, type and changes of feeding), the intrinsic factors of horses (sex, age and breed), management (type and changes of housing and activity), medical history (a previous colic, administration of a medical treatment) and parasite control...
Walesby HA, Ragle CA, Booth LC.A 12-year-old stallion was evaluated because of pollakiuria; endoscopy of the urinary tract during general anesthesia revealed that the urinary bladder was intact. After recovery, the stallion developed clinical and biochemical signs of bladder rupture, which was confirmed by endoscopy. Cystoplasty in adult stallions represents a unique surgical dilemma; the large distance between the incision site and the bladder necessitates the repair be accomplished under maximum tension with minimal exposure. Because traditional surgical approaches through ventral midline or paramedian incisions provide l...
Moore-Colyer MJ, Hyslop JJ, Longland AC, Cí·¯ord D.An in sacco mobile bag technique was used to determine the rate and extent of disappearance of unmolassed sugar-beet pulp, soyabean hulls, hay cubes and an oat hull-naked oats mixture (67:33, w/w) in the foregut and total digestive tract of ponies. Ponies were administered naso-gastrically polyester mesh bags containing 350 mg feed, in a Latin square design. Bags were collected at the ileo-caecal junction (small intestine bag, SIB) and in the faeces (faecal bag, FB) and their residues analysed for proximate constituents and NSP composition and content. DM disappearances from individual bags we...
Holcombe SJ, Cornelisse CJ, Berney C, Robinson NE.To determine whether the hyoepiglotticus muscle has respiratory-related electromyographic activity and whether electrical stimulation of this muscle changes the position and conformation of the epiglottis, thereby altering dimensions of the aditus laryngis. Methods: 6 Standardbred horses. Methods: Horses were anesthetized, and a bipolar fine-wire electrode was placed in the hyoepiglotticus muscle of each horse. Endoscopic images of the nasopharynx and larynx were recorded during electrical stimulation of the hyoepiglotticus muscle in standing, unsedated horses. Dorsoventral length and area of ...
Cable CS, Ducharme NG, Hackett RP, Erb HN, Mitchell LM, Soderholm LV.To investigate whether upper airway sounds of horses exercising with laryngeal hemiplegia and alar fold paralysis have distinct sound characteristics, compared with unaffected horses. Methods: 6 mature horses. Methods: Upper airway sounds were recorded in horses exercising on a high-speed treadmill at maximum heart rate (HR(MAX)) under 3 treatment conditions (ie, normal upper airway function [control condition], and after induction of left laryngeal hemiplegia or bilateral alar fold paralysis) in a randomized crossover design. Fundamental frequency, spectrograms using Gabor transform, and inte...
de la Calle J, Burba DJ, Ramaswamy CM, Hosgood G, Williams J, LeBlanc C, Moore RM.To compare plasma and synovial fluid endothelin-1 (ET-1) and nitric oxide (NO) concentrations in clinically normal horses and horses with joint disease. Methods: 36 horses with joint disease, and 15 horses without joint disease. Methods: Horses with joint disease were assigned to 1 of the 3 groups (ie, synovitis, degenerative joint disease [DJD], or joint sepsis groups) on the basis of findings on clinical and radiographic examination and synovial fluid analysis. Endothelin-1 and NO concentrations were measured in plasma from blood samples, collected from the jugular vein and ipsilateral cepha...
Wooldridge AA, Eades SC, Hosgood GL, Moore RM.To compare effects of oxytocin, acepromazine maleate, xylazine hydrochloride-butorphanol tartrate, guaifenesin, and detomidine hydrochloride on esophageal manometric pressure in horses. Methods: 8 healthy adult horses. Methods: A nasogastric tube, modified with 3 polyethylene tubes that exited at the postpharyngeal area, thoracic inlet, and distal portion of the esophagus, was fitted for each horse. Amplitude, duration, and rate of propagation of pressure waveforms induced by swallows were measured at 5, 10, 20, 30, and 40 minutes after administration of oxytocin, detomidine, acepromazine, xyl...
Tanaka Y, Taniyama H, Tsunoda N, Herath CB, Nakai R, Shinbo H, Nagamine N, Nambo Y, Nagata S, Watanabe G, Groome NP, Taya K.To clarify the source of inhibins in equine female fetuses, concentrations of immunoreactive (ir-) inhibin, inhibin pro-alphaC, and inhibin A in both fetal and maternal circulation and in fetal ovaries were measured. In addition, the localization of inhibin alpha and inhibin/activin beta(A), and beta(B) subunits and the expression of inhibin alpha(A) and inhibin/activin beta(A) subunit mRNA in fetal ovaries were investigated using immunohistochemistry and in situ hybridization. Concentrations of circulating ir-inhibin, inhibin pro-alphaC, and inhibin A were remarkably more elevated in the feta...
Lentz LR, Valberg SJ, Herold LV, Onan GW, Mickelson JR, Gallant EM.To determine whether alterations in myoplasmic calcium regulation can be identified in muscle cell cultures (myotubes) and intact muscle fiber bundles derived from Thoroughbreds affected with recurrent exertional rhabdomyolysis (RER). Methods: 6 related Thoroughbreds with RER and 8 clinically normal (control) Thoroughbred or crossbred horses. Methods: Myotube cell cultures were grown from satellite cells obtained from muscle biopsy specimens of RER-affected and control horses. Fura-2 fluorescence was used to measure resting myoplasmic calcium concentration as well as caffeine- and 4-chloro-m-c...
Wooldridge AA, Eades SC, Hosgood GL, Moore RM.To characterize the in vitro effects of oxytocin, acepromazine, xylazine, butorphanol, detomidine, dantrolene, isoproterenol, and terbutaline on skeletal and smooth muscle from the equine esophagus. Methods: 14 adult horses without digestive tract disease. Methods: Circular and longitudinal strips from the skeletal and smooth muscle of the esophagus were suspended in tissue baths, connected to force-displacement transducers interfaced with a physiograph, and electrical field stimulation was applied. Cumulative concentration-response curves were generated for oxytocin, acepromazine, xylazine, d...
Taylor D, Hood DM, Wagner IP.To evaluate the short-term effects of 4 therapeutic shoeing systems on lameness and voluntary limb-load distribution in horses with chronic laminitis. Methods: 10 horses with chronic laminitis. Methods: A clinical trial was conducted that used a concurrent control, crossover design to evaluate the relative effectiveness of a standard flat shoe, fullered egg-bar shoe, heart-bar shoe, and modified equine digital support system to alleviate chronic lameness in horses. Therapeutic success was assessed during a 7-day period by use of subjective (Obel grade and clinical score) and objective (force-p...
Patel JR, Földi J, Bateman H, Williams J, Didlick S, Stark R.The temperature sensitive and host range mutant clone 147 of equine herpesvirus 1 (EHV-1) was assessed for its ability to protect conventional, susceptible adult horses against respiratory infection by EHV-1 and equine herpesvirus 4 (EHV-4). Intranasal (IN) vaccination with 5.2 log(10) TCID(50) did not cause adverse clinical reactions although a limited virus shedding and viraemia (leukocytes) was observed in 11 of 15 and 10 of 15 vaccinated horses respectively. All 15 vaccinated horses showed a significant seroresponse to both EHV-1 and EHV-4 for virus neutralising (VN) antibody. None of 14 c...
Lees P, Landoni MF.Carprofen is a nonsteroidal anti-inflammatory drug of the 2-arylpropionate subclass. It contains a single chiral centre and exists in two enantiomeric forms. In this study rac-carprofen, at two dosages, 0.7 and 4.0 mg/kg, and placebo were administered i.v. to six New Forest horses in a three period cross-over study. The concentration-time profiles were established for R(-) and S(+)-carprofen for plasma and both inflamed (exudate) and noninflamed (transudate) tissue cage fluids. R(-)-carprofen was the predominant enantiomer in all three fluids, as indicated by plasma area under the curve (AUC) ...
Pusterla N, Chae JS, Kimsey RB, Berger Pusterla J, DeRock E, Dumler JS, Madigan JE.Most human granulocytic ehrlichiosis (HGE) studies carried out in horses use needle inoculation of infected leucocytes or cell cultures. This route of inoculation does not accurately reflect natural infection of the tick-borne agent. To investigate whether tick transmission influences the course of granulocytic ehrlichiosis in the horse model, experimental transmission through infected laboratory-reared Ixodes scapularis ticks was attempted into two healthy horses. One additional horse served as negative control and was exposed to uninfected ticks. Eleven days after exposure to nymphal or adul...
Tuntasuvan D, Jarabrum W, Viseshakul N, Mohkaew K, Borisutsuwan S, Theeraphan A, Kongkanjana N.During June-July 2000, an outbreak of surra occurred on an equine breeding farm in Khonkaen Province, Thailand. Forty-two percent of pregnant mares aborted or gave stillbirth and 40% (19/47) of horses and 10% (1/10) of mules died from surra. In August 2000 Trypanosoma evansi were detected in the remaining animals (28 horses and nine mules) on the farm by blood smear and/or the haematocrit centrifuge technique. All animals were treated with diminazene aceturate at 3.5 mg/kg body weight by intramuscular injection on days 0 and 41 of the study. Blood samples of eight randomly selected horses and ...
Ranner W, Gerhards H, Klee W.There is a regularly high proportion of x-ray findings indicating a pathological deterioration of the equine vertebral column which do not correlate with the clinical symptoms. Therefore, palpation remains one of the most important clinical examination methods to determine whether or not a horse is suffering from back pain. The aim of this study was to check the validity of palpation results of horses with an assumed back problem. The palpation results of 167 horses were evaluated in retrospect: If the palpation proceeds under following conditions, positive palpation results agree with an prim...
Al-Hizab F, Clegg PD, Thompson CC, Carter SD.To investigate the relationship between matrix metalloproteinase (MMP) activity and osteochondritis dissecans (OCD) in the equine joint. Methods: Equine articular cartilage was obtained from normal (N = 8) and osteochondrotic (OCD) (N = 6) femoropatellar joints from horses at necropsy. The activity of gelatinase MMPs was determined in sections of cartilage by in situ gelatin zymography. Results: Gelatinase activity was markedly increased in articular cartilage obtained from OCD samples and was particularly prominent in the deep cartilage zone. Activity was only seen in the pericellular area of...
McGowan CM, Fordham T, Christley RM.Telephone surveys of 34 racing yards with 1276 horses in training were made to establish the overall incidence of exertional rhabdomyolysis in the previous year. A case-control study was used to investigate the risk factors for the syndrome in 12 yards selected on the basis of the routine confirmation of diagnoses by the evaluation of the serum activities of creatine kinase and aspartate aminotransferase. The overall incidence of the syndrome was 6.7 per cent and 80 per cent of the trainers had at least one affected horse. In 74 per cent of the affected horses it frequently recurred, with an a...
Hudak PF.Ratios of conservative chemicals have been used to identify sources of groundwater contamination. While chloride/bromide ratios have been reported for several common sources of groundwater contamination, little work has been done on leachate derived from farm-animal waste. In this study, chloride/bromide ratios were measured in leachate derived from longhorn-cattle, quarterhorse, and pygme-goat waste at a farm in Abilene, Texas, USA. (Minimum, median, and maximum) chloride/bromide ratios of (66.5, 85.6, and 167), (119, 146, and 156), and (35.4, 57.8, and 165) were observed for cattle, horses, ...
Auge BK, Preminger GM.The surgical management of urinary calculus disease has changed dramatically in the past two decades. Minimally invasive options have made open stone surgery nearly obsolete. The development of shock wave lithotripsy, percutaneous nephrostolithotomy techniques and intracorporeal lithotripsy devices has conferred unprecedented management tools for upper tract stones. Moreover, transfusion rates, hospital costs, and convalescence periods have been markedly reduced when compared to open surgery. Likewise, the advent of fiberoptic technology has resulted in miniaturization of ureteroscopes making ...
Eenoo PV, Delbeke FT.Salbutamol is a beta-adrenergic agonist that is used in the treatment of asthma in humans and chronic obstructive pulmonary disease in horses. Because of its stimulating and growth promoting properties, it is prohibited by horse racing authorities. Recently a number of adapters (eg Equinehaler) have been designed, allowing the use of metered dose inhalers (MDI) approved for human use. However, information on detection times of salbutamol after administration of salbutamol in therapeutic doses by inhalation is lacking. In this study, 2 mg salbutamol (Ventolin) was administered to four standardb...
Wiemer P, Bergman HJ, van der Veen H, Pruissen L.In the period from January 1995 until December 2000, 272 horses underwent a laparotomy for gastrointestinal disorders. The results of these surgeries were evaluated. From these 272 patients 176 (= 65%) were discharged in good health from the hospital. When the patients that were euthanized immediately after the start of the surgery, because of a fatal deterioration, were not taken into account, the short time survival rate was 77%. Strangulated small and large intestinal obstructions (48%) had a lower short time survival rate than non-strangulated obstructions (87%). Fatal postoperative compli...
O'Callaghan MW.There is increasing demand on equine practitioners to provide confirmation of their diagnoses. For obscure lameness and for many of the more difficult locomotory problems presented in referral hospitals, the question to be answered is not only how to make the most accurate diagnosis but also how to document the findings so that there is less doubt in the mind of the client. This article describes a quasi algorithmic approach to choosing the best combinations of the increasingly sophisticated imaging methods available for evaluation of orthopedic disease.
Hardman C, McIlnay TR, Dugan SJ.A 3-year-old Paint gelding was presented for sudden onset of cataract affecting the right eye. Ophthalmic examination revealed subtle to mild microphthalmia and a mature cataract affecting the right globe. The right eye was treated with an antibiotic-corticosteroid ophthalmic ointment and phacofragmentation was recommended. On re-examination 5 months later, resorption of the cortex of the right lens and a morgagnian cataract were evident. The nucleus was positioned ventronasally in the lens capsule. The right eye had light perception, and a menace response was present. Examination of the right...
Ambrisko TD, Lammer V, Schramel JP, Moens YP.A spirometry device equipped with mainstream CO2 flow sensor is not available for large animal anaesthesia. Objective: To measure the resistance of a new large animal spirometry device and assess its agreement with reference methods for volume measurements. Methods: In vitro experiment and crossover study using anaesthetised horses. Methods: A flow partitioning device (FPD) equipped with 4 human CO2 flow sensors was tested. Pressure differences were measured across the whole FPD and across each sensor separately using air flows (range: 90-720 l/min). One sensor was connected to a spirometry ...
Nagata S, Kurosawa M, Kuwajima M.A new enzyme immunoassay (EIA) for the measurement of furosemide in horse plasma is described. The lower limit of detection of this EIA method was 7.8 ng/ml. The intra-and inter-assay coefficients of variation ranged from 2.5% to 4.9% and 7.5% to 9.8%, respectively. Cross-reactivity with other compounds was not observed. There was a high correlation (r2=0.987) between the high-performance liquid chromatography and EIA results obtained for furosemide concentrations in horse plasma. These results indicate that the newly developed EIA method is useful for the quantitative analysis of furosemide i...
van der Kolk JH, Kalsbeek HC, Wensing T, Breukink HJ.The urinary corticoid:creatinine (c:c) ratio was determined in eight horses with hyperadrenocorticism (HAC). The mean (+/- SD) urinary c:c ratio of the eight horses with HAC (29 +/- 14 x 10(-6)) was significantly (P < 0.05) greater than the ratio in seven control horses (11 +/- 4.3 x 10(-6)). The urinary concentration of corticoids in control horses (201 +/- 60.4 nmol litre-1) was significantly (P 0.05) between both groups. As both false negative and false positive cases were found, it is concluded that a measurement of the urinary c:c ratio in the horse should not be used as the sole test...
Orsini JA, Kreuder C.Musculoskeletal disorders in newborn foals are complex, multifactorial, and associated with prematurity, dysmaturity, and twinning. They include incomplete ossification of cuboidal bones, tendon laxity, congenital angular limb deformities, septic arthritis, osteomyelitis, and septicemia. Other deformities associated with nutrition, large size, and rapid growth include osteochondrosis, physitis, ruptured tendons, acquired flexural deformities, and postnatal angular limb deformities. Optimal management of the complexly interrelated musculoskeletal disorders of the neonate also is discussed.
Sanmartí J, Armengou L, Troya-Portillo L, Robles-Guirado JÁ, Bassols A, Ríos J, Jose-Cunilleras E.Magnesium disorders in horses with gastrointestinal disorders or systemic inflammatory response syndrome (SIRS) are scarcely characterized. The purpose of the study was to explore the association of magnesium disorders with diagnosis, SIRS and mortality in horses admitted to a referral equine hospital. In total, 75 sick horses were included in an observational prospective study and classified as: obstructive ( = 17), inflammatory ( = 10) and ischemic gastrointestinal disorders ( = 12), and other non-gastrointestinal systemic disorders ( = 36). All sick horses were also divided according to the...
Treonze KM, Alves K, Fischer P, Hagmann WK, Hora D, Kulick A, Vakerich K, Smith ND, Lingham RB, Maniar S, Reger TS, Zunic J, Munoz B, Prasit P....The purpose of this study was to characterize the alpha(4)beta(1) receptor (CD49d/CD29, very late antigen-4, VLA-4) on circulating equine leukocytes and to evaluate the intrinsic potency of an alpha(4)beta(1) receptor antagonist (Compound B) in the horse. Ultimately, these studies would allow us to determine the suitability of treating recurrent airway obstruction (RAO; heaves) affected horses by blocking the cellular recruitment of lymphocytes and neutrophils into the lung. The data demonstrates the alpha(4)beta(1) integrin is present on horse lymphocytes and neutrophils (fluorescence-assiste...
Elte Y, Acton K, Martin J, Nielen M, van Weeren R, Wolframm I.Individuals working in the field of veterinary care are regularly affected by their profession. High levels of responsibility to often provide life-saving health care to animals combined with having to manage owners' expectations and irregular working hours can cause considerable levels of work-related stress among professionals in equine veterinary practice. On the positive side, research also shows that working in the veterinary profession can have a positive impact on personal wellbeing and feelings of fulfillment. A limited number of studies has investigated work satisfaction and engagemen...
Pusterla N, Barnum SM, Byrne BA.Polymerase chain reaction (PCR)-based detection assays for Streptococcus equi subspecies equi often overestimate the prevalence of samples containing viable organisms. The objective of this study was to determine if viability could be determined using genome quantitation and detection of messenger RNA (mRNA) transcripts for the SeM gene of S. equi in pre- and post-cultured samples. Nasal secretions collected from 42 horses with suspected strangles were tested by culture and by quantitative PCR (qPCR) before and 24 hours after a culture step. Viable S. equi was determined based on the detecti...
You Y, Proctor RM, Guo K, Li X, Xue E, Guan F, Robinson MA.High-resolution mass spectrometry (HRMS) is a very powerful technology for equine doping control analysis. The more recently developed hybrid type of Orbitrap-based HRMS instrument allows for both targeted and non-targeted screening analyses in a single liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) run. In the present study, an LC-HRMS/MS method was developed and validated to detect prohibited substances in equine sports. The substances were recovered from equine plasma by liquid-liquid extraction (LLE) using methyl tert-butyl ether and were separated on a C18 rev...
Heath MF, Evans RJ, Hayes LJ.Dextrans of mean molecular weight 70 kDa (dextran-70) have had clinical use as anti-thrombotics in man. A major part of the anti-thrombotic action is mediated via inhibition of platelet function. Greatorex (1975, 1977) treated thromboembolic colic in horses with infusions of dextran-70 and reported a 90% recovery rate, but this treatment is nonetheless rarely used. We have used an in vitro method to examine the effect of dextran-70 on equine platelet suspensions, in the hope that understanding the mechanism of action of dextran-70 might lead to the development of alternative therapeutic agents...
Moens Y.The mechanical ventilation of horses during anesthesia remains a crucial option for optimal anesthetic management, if the possible negative cardiovascular side effects are managed, because this species is prone to hypercapnia and hypoxemia. The combined use of capnography and pitot-based spirometry provide complementary information on ventilation and respiratory mechanics, respectively. This facilitates management of mechanical ventilation in conditions of changing respiratory system compliance (ie, laparoscopy) and when investigating new ventilatory strategies including alveolar recruitment m...
Ayala-Valdovinos MA, Galindo-García J, Sánchez-Chiprés D, Duifhuis-Rivera T, Anguiano-Estrella R.The 'Gait keeper' mutation in the DMRT3 gene alters locomotion and gait patterns in horses. This mutation (C>A) has been found in all gaited breeds of horses analyzed but is absent in most non-gaited breeds. We developed a new mutagenically separated polymerase chain reaction (MS-PCR) based method for simple detection of horse DMRT3 genotype. Our method was applied in a preliminary study to determine DMRT3 allele frequencies in 78 Azteca horses (AZ) and 53 Costa Rican Saddle Horses (CRSH). We found a wild-type C allele frequency of 100% in the AZ horses. For the CRSH, the wild-type C freque...
Bergh A, Nyman G, Lundeberg T, Drevemo S.Treatment with defocused CO2 laser can have a therapeutic effect on equine injuries, but the mechanisms involved are unclear. A recent study has shown that laser causes an increase in equine superficial tissue temperature, which may result in an increase in blood perfusion and a stimulating effect on tissue regeneration. However, no studies have described the effects on equine tissue perfusion. The aim of the present study was to investigate the effect of defocused CO2 laser on blood perfusion and to correlate it with temperature in skin and underlying muscle in anaesthetized horses. Differenc...
Guo X, Aoyama M, Sugita S.Three optic nerves (L1, R2, R3) 12-18 mm behind the eyeball of the horse (Thoroughbred) were investigated quantitatively under light and electron microscopes. Thin sections at the thickness of 0.35 microm were cut, stained by toluidine blue and observed under the light microscope. The areas of the optic nerve and the axon bundles were 20.03 +/- 1.04 and 16.59 +/- 0.79 mm2 (mean +/- SD, n=3), respectively. The axon numbers for optic nerve L1, R2 and R3, estimated from light micrographs, were about 481 x 10(3), 543 x 10(3), and 494 x 10(3), respectively. Axons of optic nerve L1 were also counted...
Zehetner V, Cavalleri JV, Klang A, Hofer M, Preining I, Steinborn R, Ramsauer AS.There is strong evidence that equine parvovirus-hepatitis (EqPV-H) is associated with the onset of Theiler's disease, an acute hepatic necrosis, in horses. However, the impact of this virus on other hepatopathies remains unknown. The objective of this retrospective study was to evaluate the prevalence and quantify the viral loads of EqPV-H in formalin-fixed, paraffin-embedded equine and donkey livers with various histopathologic abnormalities. The pathologies included cirrhosis, circulatory disorders of the liver, toxic and metabolic hepatic diseases as well as neoplastic and inflammatory dise...
Ouellette AL, Evans RJ, Heath MF.Endotoxaemia is the leading cause of death in horses. Disseminated intravascular coagulation (DIG), stimulated by induced monocyte proteins, is a prominent feature. Monocyte-platelet cellular interactions are central to the vascular dysfunction produced by circulating endotoxin and are implicated in many thrombotic diseases in the horse. This study reports that endotoxin (0.01-10 microg ml(-1)) and blood platelets (2.5 x 10(7) - 1 x 10(8) ml(-1)) are potent inducers of expression and activity of monocyte tissue factor (TF), the primary activator of the blood coagulation protease cascade. The c...
Zerpa H, Berhane Y, Elliott J, Bailey SR.The equine hoof displays thermoregulatory functions, and the blood vessels lying under the hoof wall are temperature sensitive. The aim of this study was to investigate the effect of cooling on the contractile responses to α-adrenoceptor and 5-HT receptor stimulation in equine small lamellar arteries using wire myography. The role of the endothelium in the response mediated by 5-HT was also evaluated. Moderate cooling caused a reduction of the contraction induced by depolarizing Krebs solution (DKS, containing 118 mm KCl) and the maximal contraction caused by UK-14304 (α(2)-adrenoceptor agon...
Bump KD, Lawrence LM, Moser LR, Miller-Graber PA, Kurcz EV.1. Muscle samples from the M. gluteus medius were obtained from six Quarter Horses (QH), six Thoroughbreds (TB), and five Standardbreds (SB) to determine carnosine values and fiber type percentages. 2. Muscle biopsies were for fiber type percentages and carnosine concentration. 3. QH had a lower percentage of slow twitch oxidative fibers and a higher percentage of past twitch glycolytic fibers than SB or TB. 4. Fast twitch oxidative-glycolytic fibers were lowest in the QH. 5. The QH had mean carnosine values significantly greater (P less than 0.01) than the mean values for SB and TB. 6. Across...
Hartig W, Houe H, Andersen PH.At present Denmark has no central database holding records of equine health and disease. Nor have attitudes to the establishment of a national database, and the concerns it raises, been investigated in a systematic way. The objective of the present study was to assess the attitudes and concerns of potential database stakeholders. Attitudes to participation, and the location, financing and management of the proposed database, together with any concerns it raises, were investigated in a questionnaire study of 13 potential stakeholder groups in Denmark (in total, 1581 questionnaire recipients and...
Holmes JR, Alps BJ.The paper describes the changes in P, QRS and T vector orientations in the H plane in the aberrant beats in cases of partial atrioventricular block and premature atrial and ventricular systoles. The sites of possible atrial ectopic foci are discussed in relation to the anatomy of the atrial chambers and the orientation of the P vectors associated with atrial ectopic beats.
Argo CM, Turnbull EB.Spherical (35 mm diameter) glass intra-uterine devices (IUDs) are commonly understood to modify sexual behaviour in performance mares. The effect of IUDs on the endocrinology (luteinising hormone, oestradiol, progesterone, testosterone), ovarian and uterine function, sexual and social behaviours associated with the ovarian cycle were evaluated during the natural breeding season in nine, nuliparous pony mares (4.6±0.5 years old, 230±12 kg bodyweight). Age and weight-matched groups were allocated to sham-treatment (n=5) or IUD-implantation (n=4) groups. Fifty complete ovarian cycles were evalu...
Piercy RJ, Swardson CJ, Hinchcliff KW.A Standardbred gelding and a colt were examined because of poor performance and anemia. Each horse had been given recombinant human erythropoietin (rhEPO; 4,000 IU) at least twice within the preceding 2 to 4 months. The horses had an Het of 16 and 24%, serum iron concentrations of 210 and 304 micrograms/dl (reference range, 73 to 140 micrograms/dl), total iron binding capacities of 239 and 321 micrograms/dl (reference range, 266 to 364 micrograms/dl), values for the percentage saturation of transferrin by iron of 87.9 and 94% (reference range, 20 to 52%), and serum ferritin concentrations of 2...
Adams RJ, Mollenkopf DF, Mathys DA, Whittle A, Ballash GA, Mudge M, Daniels JB, Barr B, Wittum TE.To estimate the prevalence of extended-spectrum cephalosporin-, carbapenem-, and fluoroquinolone-resistant bacteria of the family Enterobacteriaceae in the feces of hospitalized horses and on hospital surfaces. Methods: Fecal and environmental samples were collected from The Ohio State University Galbreath Equine Center (OSUGEC) and a private referral equine hospital in Kentucky (KYEH). Feces were sampled within 24 hours after hospital admission and after 48 hours and 3 to 7 days of hospitalization. Methods: Fecal and environmental samples were enriched, and then selective media were inoculate...
