Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Ragle CA.Laparoscopic cystotomy is the method of choice for treatment of a cystic calculus in the horse. The main advantage of this procedure over others is the excellent ability to view and gain operative access to the urinary bladder. This article describes the procedure, including techniques, instrumentation, preoperative and postoperative care, and complications.
Shettko DL.As laparoscopic surgery gains popularity, it becomes crucial to understand complications associated with the procedure. The potential complications of laparoscopy include those related to laparoscopy and those related to the surgical procedure. As new applications for laparoscopic surgery emerge, it is important for the surgeon to become familiar with potential complications.
Dechant JE, Hendrickson DA.Standing female urogenital endoscopic surgery is facilitated by the more dorsal location of the organs of the female reproduction tract. The most common reason for laparoscopic surgery on the female urogenital system is ovariectomy; however, the technique has been used to diagnose periparturient or reproductive diseases and to perform surgical embryo transfer. Standing surgical approaches avoid the risk and expense of general anesthesia, but these techniques are limited by the temperament and size of the patient and the availability of facilities for restraint. Owner acceptance of laparoscopic...
Wilson DG.Possibly no other development has revolutionized general surgery more dramatically than laparoscopic surgery in human patients. The development of instrumentation suitable for use in horses has allowed the veterinary surgeon to begin to introduce minimally invasive procedures. Clearly, in people, one of the greatest benefits is reduced patient morbidity and earlier return to function. The author's experience with laparoscopic procedures in the horse would tend to reinforce those observations. The most significant obstacle to widespread acceptance of minimally invasive surgery in the horse is p...
Trostle S.A working knowledge of normal endoscopic anatomy and the effects of positioning must be mastered to take advantage of endoscopic procedures involving the gastrointestinal system. Endoscopic procedures involving the gastrointestinal system offer advantages over conventional surgery in that they are less invasive and provide direct visualization. Laparoscopy can be used to evaluate horses with abdominal pain before and after surgery. It can be used to evaluate and biopsy abdominal masses and parenchymal organs such as the spleen, liver, and kidney. Endoscopic gastrointestinal surgical procedures...
Hendrickson DA.Equine surgery continues to benefit from advances in endoscopic surgical techniques. Much of what we have learned in equine endoscopy comes from techniques used in humans. Descriptions of the normal anatomy of the standing horse and advances in instrumentation have improved our ability to perform laparoscopic surgery in standing and dorsally recumbent horses. This article describes the history of laparoscopy and available instrumentation.
Trumble TN, Hendrickson DA.Standing laparoscopy in the horse was used initially as a diagnostic tool to assist in the diagnosis of a cryptorchid testicle. Now, this technique is also used for treatment of cryptorchid testicles. The focus of this article is the standing laparoscopic cryptorchidectomy, the most common laparoscopic procedure performed on the male equine urogenital tract. Advantages, disadvantages, instrumentation, and general procedure are discussed.
Ragle CA.The ventral abdominal approach for laparoscopy is versatile. Reported techniques using a ventral approach in the mare include bilateral ovariectomy and granulosa cell tumor removal. Laparoscopic ovariectomy is performed by way of four instrument portals in the caudoventral aspect of the insufflated abdomen. The procedure has several advantages over the traditional approaches of colpotomy and celiotomy, including tension-free closure of all incisions and minimal invasiveness.
Shoemaker RW, Read EK, Duke T, Wilson DG.The feasibility of leaving the ovaries within the peritoneal cavity after laparoscopic coagulation and transection of the ovarian pedicle was assessed in the juvenile horse. Elective ovariectomy was performed on 10 quarter horses, aged 4 to 5 mo, with the fillies in a Trendelenburg position. The mesovarium was isolated, and multiple coagulation and transection cycles were performed until all ovarian attachments had been severed. The ovaries were dropped within the abdomen, and hemostasis of the transected mesovarium was evaluated before closure. The mean surgical time was 33 min (range, 23 to ...
Scotty NC, Cutler TJ, Brooks DE, Ferrell E.To define the indications for equine ocular ultrasonography and to provide representative ultrasonographic images of lens and posterior segment diseases. Methods: Retrospective study. Equine medical records dating from January 1983 to March 2001 were reviewed. All cases that: (1) had a lens and/or posterior segment abnormality; and (2) received a complete ophthalmic examination and ocular ultrasonography were included. Results: Forty-three cases (n = 64 eyes) out of 112 total cases of equine lens and/or posterior segment abnormalities qualified. The following conditions were identified ultraso...
Gomez JH, Schumacher J, Lauten SD, Sartin EA, Hathcock TL, Swaim SF.Three biologic dressings [split-thickness allogeneic skin (STS)], allogeneic peritoneum (P), and xenogenic porcine small intestinal submucosa (PSIS)] were studied to determine their effects on bacterial proliferation, inflammatory reaction, vascularization, and overall healing and to compare the effects of these dressings with the effects of a nonbiologic dressing, a nonadherent synthetic pad (NASP). A medial wound (3 cm in diameter) and 2 lateral wounds (2 cm in diameter) were created at the junction of the proximal and middle thirds of each metacarpus and metatarsus in 5 horses. Each medial ...
Raudsepp T, Lee EJ, Kata SR, Brinkmeyer C, Mickelson JR, Skow LC, Womack JE, Chowdhary BP.Development of a dense map of the horse genome is key to efforts aimed at identifying genes controlling health, reproduction, and performance. We herein report a high-resolution gene map of the horse (Equus caballus) X chromosome (ECAX) generated by developing and typing 116 gene-specific and 12 short tandem repeat markers on the 5,000-rad horse x hamster whole-genome radiation hybrid panel and mapping 29 gene loci by fluorescence in situ hybridization. The human X chromosome sequence was used as a template to select genes at 1-Mb intervals to develop equine orthologs. Coupled with our previou...
Kavazis AN, Kivipelto J, Choe HS, Colahan PT, Ott EA.The objective of this study was to investigate the effects of ribose supplementation on blood ammonia-N, plasma lactic acid, plasma glucose, volume of oxygen consumption (VO2), heart rate, and performance in Thoroughbred geldings performing a maximal treadmill standardized exercise test (SET). The hypothesis tested was that ribose supplementation would decrease ammonia-N and lactic acid accumulation during exercise, and improve performance. Eight Thoroughbred geldings were assigned randomly to one of two groups: glucose or ribose. The glucose group received 0.15 g glucose/kg of BW, and the rib...
Kleiboeker SB, Loiacono CM, Rottinghaus A, Pue HL, Johnson GC.The North American West Nile virus (WNV) epizootic, which began in 1999, has caused significant morbidity and mortality in horses. Because experimental infection has failed to consistently produce encephalitis in inoculated horses, investigation of naturally occurring cases was used to optimize strategies for diagnosis of this disease. Although WNV RNA could be detected by reverse transcriptase-polymerase chain reaction (RT-PCR) performed on whole blood collected from both clinically affected horses and unaffected herdmates, the diagnostic sensitivity of this approach was low compared with IgM...
Mitchell SR, Kempson SA, Dixon PM.The structure of peripheral cementum of mandibular and maxillary cheek teeth was studied by gross observation, light microscopy, and scanning and transmission electron microscopy. Teeth from four horses aged 4, 8, 17, and 30-years-old were examined. The cementum of the occlusal surface was thicker on the buccal aspect when compared with the lingual aspect of mandibular teeth. The cementum of the occlusal surface was thicker on the palatal aspect when compared with the buccal aspect of maxillary teeth. There was no peripheral cementum on the interdental aspects of either mandibular or maxillary...
Swanstrom MD, Stover SM, Hubbard M, Hawkins DA.To determine the relative contributions of the muscles, tendons, and accessory ligaments to the passive force-length properties of the superficial (SDF) and deep digital flexor (DDF) myotendinous complexes. Methods: 8 cadaveric forelimbs from 6 adult Thoroughbreds. Methods: In vitro, limb configurations during slack position and myotendinous lengths during subsequent axial loading of forelimbs were recorded before and after transection of accessory ligaments. Expressions were derived to describe the force-length behavior of each muscle, tendon, and accessory ligament-tendon unit; linear stiffn...
Pauwels FE, McClure SR, Amin V, Van Sickle D, Evans RB.To measure changes in the modulus of elasticity (E) and describe histologic findings after extracorporeal shock wave therapy and radial pressure wave therapy on equine cortical bone specimens. Methods: 16 bone specimens from the proximodorsal cortex of an equine third metacarpal or metatarsal bone. Methods: Baseline E was determined by the density (p) and unidirectional ultrasound transmission velocity (C) of each specimen according to the equation E = pC2. Eight specimens were treated with 500 pulses of 0.15 mJ/mm2 of extracorporeal shock wave therapy, and 8 specimens were treated with 500 pu...
Davenport-Goodall CL, Boston RC, Richardson DW.To investigate the effects of insulin-like growth factor-II (IGF-II) on DNA and glycosaminoglycan (GAG) synthesis and the expression of matrix-related genes in equine articular cartilage explants and chondrocytes, respectively, with and without interleukin 1-beta (IL1-beta). Methods: Articular cartilage from 12 adult horses. Methods: Articular cartilage was incubated in standard media with and without equine IL1-beta (10 ng/mL) containing various concentrations of IGF-II for 72 hours. Synthesis of DNA and GAG was determined by incorporation of thymidine labeled with radioactive hydrogen (3H) a...
Kleiboeker SB, Turnquist SE, Johnson PJ, Kreeger JM.In previous studies, novel putative viral pathogens designated that asinine herpesvirus 4 (AsHV4) and asinine herpesvirus 5 (AsHV5) were associated with fatal interstitial pneumonia in donkeys (Equus asinus). Nucleotide sequence analysis of a portion of the DNA polymerase gene identified these putative pathogens as herpesviruses and possibly as members of the Gammaherpesvirinae subfamily. Although similar to equine herpesvirus 2 (EHV2) and equine herpesvirus 5 (EHV5), sequence diversity was observed among the detected viruses. In this study, novel sequence is reported for a DNA-packaging prote...
Williams CA, Kronfeldt DS, Hess TM, Saker KE, Waldron JN, Crandell KM, Hoffman RM, Harris PA.This study tested the development of oxidative stress and the effects of antioxidant supplementation in an 80-km ride. A precompetition survey revealed that no competitor would participate without vitamin E supplementation; therefore, 46 horses were paired for past performances and randomly assigned to two groups of 23 each for 3 wk of supplementation before the ride. One group (E) was orally supplemented with 5,000 IU of vitamin E per day; the other group (E+C) received that dose of vitamin E plus 7 g/d of vitamin C. Blood samples, temperature, and heart rate were taken the day before the rac...
Tetens J, Moore RM, Hosgood GL, Eades SC, Keowen ML, Horohov DW.To evaluate systemic effects of i.v. infusion of ATP-MgCl2 subsequent to infusion of a low dose of endotoxin in horses. Methods: 12 adult horses. Methods: Horses were administered endotoxin (lipopolysaccharide [LPS]) or saline (0.9% NaCl) solution i.v., during a 30-minute period. Immediately thereafter, horses in each group were infused i.v. with ATP-MgCl2 or saline solution. Two weeks later, horses were administered the opposite solution (LPS or saline solution), but it was followed by the same infusion as 2 weeks previously (ie, ATP-MgCl2 or saline solution). Cardiopulmonary and clinicopatho...
Licka TF, Peham C, Frey A.To use electromyography (EMG) to measure physiologic activity of the longissimus dorsi muscles of horses during trotting on a treadmill. Methods: 15 adult horses (5 to 20 years old that weighed 450 to 700 kg) that did not have clinical signs of back pain. Methods: Data were recorded for each horse during trotting on a treadmill at speeds of 2.6 to 4.4 m/s. Surface electromyography was recorded bilaterally from the longissimus dorsi muscles at the levels of T12, T16, and L3. Results: In each motion cycle, 2 EMG maxima were found at the end of the diagonal stance phases. The EMG activity peaked ...
McKenzie HC, Murray MJ.To assess gentamicin concentrations in serum and bronchial lavage fluid (BLF) of horses during a 24-hour period after once-daily aerosol administration of gentamicin (GAER) for 7 days and the pattern and degree of bronchial tree inflammation associated with repeated GAER. Methods: 13 healthy adult horses (9 geldings and 4 mares). Methods: The treatment group comprised 8 horses, and 5 horses were untreated control animals. Gentamicin (20 mL of gentamicin [50 mg/mL]) was administered via aerosol once daily for 7 days. Samples of serum and BLF were obtained from all horses before GAER and 0.5, 4,...
Billinghurst RC, Brama PA, van Weeren PR, Knowlton MS, McIlwraith CW.To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. Methods: 43 Dutch Warmblood foals with varying severity of osteochondrosis. Methods: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined...
Valentine BA, Del Piero F, Edwards RB.Intramuscular desmoid tumors (musculoaponeurotic fibromatosis) were discovered in two young adult horses. The tumor in one horse was in the lateral cervical musculature, and that in the second horse occurred in the pectoral musculature. Histopathologic features were similar in both horses and included proliferation of fibroblasts and cells expressing muscle actin (myofibroblasts), with extensive dissecting fibrosis within muscle. These features are similar to those of desmoid tumors in humans, particularly those also known as musculoaponeurotic fibromatosis. Dissection of these lesions reveale...
Oikawa M, Narama I.Two cases of enthesopathy of the radial tuberosity in Thoroughbred racehorses are described. Soft X-ray pictures revealed separated bony fragments at the anterior aspect of the radial tuberosity, resembling the lesions of Osgood-Schlatter disease in children. Osgood-Schlatter lesions result from detachment of a portion of the apophysis of the tibial tuberosity. However, in the affected horses, the detached bony fragments consisted of cortical bone tissue composed of trabeculae with osteons similar to lamellar bone, the main component of the radial tuberosity. Tendon fibrils were inserted into ...
Meyer ND, Bayly WM, Sides RH, Wardrop KJ, Slinker BK.Prolonged equine exercise can cause hypochloraemic alkalosis and hypokalaemia secondary to the loss of hypertonic sweat. Movement of ions in and out of erythrocytes during exercise may help regulate acid-base balance and changes in plasma ion concentrations. The extent to which this happens during prolonged equine exercise has not been reported. Objective: To measure changes in blood gases and major plasma and intraerythrocytic (iRBC) ion concentrations of horses undergoing prolonged submaximal exercise. Methods: Six horses were trotted at ∼ 30% VO2max on a treadmill for 105 min. Arterial ((...
Malhotra DV, Banerjee DP, Gautam OP.The prevalence of Babesia equi infection in north west India was assessed by means of the capillary tube agglutination (CA) test. The particulate antigen used in the test was potent and no cross reaction with other related haemaprotozoa was observed. The serological survey showed that from 323 horses from 3 localities there was an overall incidence of 50.1 per cent. In Haryana the incidence was 38.3 per cent in the 196 horses tested, in Uttar Pradesh it was 47.2 per cent from 72 animals and in Rajasthan it was 96.4 per cent from 55 horses.
Joonè CJ, Schulman ML, Fosgate GT, Claes ANJ, Gupta SK, Botha AE, Human A, Bertschinger HJ.Circulating anti-Müllerian hormone concentration (AMH) is positively correlated to the number of small growing follicles in the mare and may reflect ovarian function. Dynamics of AMH during immunocontraception have not previously been investigated. This study aimed to compare serum AMH in mares following treatment with native porcine zona pellucida (pZP), recombinant pZP3 and pZP4 (reZP) or gonadotrophin releasing hormone (GnRH) vaccines, and saline-treated controls. Stored sera collected during two previous studies examining ovarian activity in mares during zona pellucida (ZP) or GnRH immuno...
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.
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.
McLean RG.The epidemic strain of Venezuelan equine encephalitis virus (VEE) 1B invaded south Texas in 1971. The success of the eventual containment and control of the virus invasion was the early recognition and immediate detection, cooperation, coordination, and participation among multiple federal agencies. There were 4739 wild vertebrate animals trapped on a ranch in the area with only 1 VEE virus isolation from a Virgina opossum (Didelphis virginiana). A large number of mosquitoes were also collected on the ranch and tested, resulting in 240 VEE virus isolations. Virus isolations were obtained from ...
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...
