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.
Clode AB, Miller C, McMullen RJ, Gilger BC. To compare the complications and nonrecurrence rate following topical mitomycin C (MMC) therapy vs. CO(2) laser ablation for treating equine corneolimbal squamous cell carcinoma (SCC). Methods: Retrospective study. Methods: Twenty-five horses with corneolimbal SCC. Methods: Medical records of horses undergoing surgical tumor resection followed by either topical MMC therapy (0.04%) or CO(2) laser ablation between the years of 2004 and 2010 were reviewed. Recurrence and complications were compared between groups and within MMC subgroups defined by the time at which treatment was ...
Smrkovski OA, Koo Y, Kazemi R, Lembcke LM, Fathy A, Liu Q, Phillips JC.Performance and clinical characteristics of a novel hyperthermia antenna operating at 434 MHz were evaluated for the adjuvant treatment of locally advanced superficial tumours in cats, dogs and horses. Electromagnetic simulations were performed to determine electric field characteristics and compared to simulations for a flat microwave antenna with similar dimensions. Simulation results show a reduced skin surface and backfield irradiation and improved directional irradiation (at broadside) compared to a flat antenna. Radiated power and penetration is notably increased with a penetration depth...
Strand E, Fjordbakk CT, Sundberg K, Spangen L, Lunde H, Hanche-Olsen S.Two genetically and phenotypically distinct horse breeds are used for harness racing in Scandinavia: the Standardbred (SB) and Coldblooded Trotter. These racehorses have identical environmental, management and racing conditions. Therefore, this study was undertaken to identify and compare the relative prevalence of upper respiratory tract (URT) obstructive disorders in these 2 breeds. Objective: To determine whether these 2 phenotypically different breeds of harness racehorses have different predispositions for URT disorders. Methods: Retrospective study of 88 Norwegian Coldblooded Trotters (N...
Costa DG, Marvulo MF, Silva JS, Santana SC, Magalhães FJ, Filho CD, Ribeiro VO, Alves LC, Mota RA, Dubey JP, Silva JC.Fernando de Noronha is an archipelago of 21 islands and islets in the Atlantic Ocean, state of Pernambuco, Brazil, which has a varied biodiversity including alien species or sinantropic animals. The objective here was to determine the seroprevalence of Toxoplasma gondii in domestic and wild animals from Fernando de Noronha archipelago, Brazil. Between July 2007 and May 2010, blood samples were collected from 764 animals (533 domestic and 231 wild animals). Sera were tested by the indirect fluorescence antibody test (IFAT) or the modified agglutination test (MAT), or by both. Antibodies to T. g...
Hoogewijs MK, de Vliegher SP, Govaere JL, de Schauwer C, de Kruif A, van Soom A.Sperm motility is considered to be one of the key features of semen analysis. Assessment of motility is frequently performed using computer-assisted sperm analysis (CASA). Nevertheless, no uniform standards are present to analyse a semen sample using CASA. Objective: We hypothesised that the type of counting chamber used might influence the results of analysis and aimed to study the effect of chamber type on estimated concentration and motility of an equine semen sample assessed using CASA. Methods: Commonly used disposable Leja chambers of different depths were compared with disposable and re...
Caniglia CJ, Schramme MC, Smith RK.Collagen fibril size is decreased in repair tissue following tendon injury compared to normal tendon matrix in horses. Mesenchymal stem cells have been suggested to promote regeneration of tendon matrix rather than fibrotic repair following injury, although this concept remains unproven. Objective: To explore the hypothesis that implantation of autologous mesenchymal stem cells derived from bone marrow into a surgically created central core defect in the superficial digital flexor tendon (SDFT) of horses would induce the formation of a matrix with greater ultrastructural similarities to tendon...
Freeman KD, Southwood LL, Lane J, Lindborg S, Aceto HW.Infections are common complications in post operative colic patients. It is the impression of some surgeons that pyrexia in the early post operative period is a sign of infection and appropriate timing of perioperative antimicrobials will decrease the incidence of post operative infection. Objective: To determine the association between 1) post operative pyrexia and development of infection and 2) perioperative antimicrobial drug use and infection rate in post operative colic patients. Methods: Medical records of patients undergoing surgical treatment for colic were reviewed. Horses recovering...
Bisanzio D, Giacobini M, Bertolotti L, Mosca A, Balbo L, Kitron U, Vazquez-Prokopec GM.West Nile Virus (WNV) transmission in Italy was first reported in 1998 as an equine outbreak near the swamps of Padule di Fucecchio, Tuscany. No other cases were identified during the following decade until 2008, when horse and human outbreaks were reported in Emilia Romagna, North Italy. Since then, WNV outbreaks have occurred annually, spreading from their initial northern foci throughout the country. Following the outbreak in 1998 the Italian public health authority defined a surveillance plan to detect WNV circulation in birds, horses and mosquitoes. By applying spatial statistical analysi...
Lovati AB, Corradetti B, Lange Consiglio A, Recordati C, Bonacina E, Bizzaro D, Cremonesi F.Mesenchymal stem cells have been recently investigated for their potential use in regenerative medicine. Population of adult stem cells were recently identified in human and lab animal tendons, but no detailed investigations have been made in the equine species. The aim of our study is to identify a progenitor cell population from tendon tissue (TSPCs) in the horse superficial digital flexor tendon that are able to be highly clonogenic, to grow fast and to differentiate in different induced cell lineages as well as bone marrow derived progenitor cells (BM-MSCs). The hypothesis that TSPCs posse...
Schramel J, Nagel C, Auer U, Palm F, Aurich C, Moens Y.The regional distribution of ventilation in conscious standing pregnant Shetland pony mares was investigated by Electrical Impedance Tomography (EIT). Six ponies were repeatedly examined a minimum of four weeks prior to (antepartum, AP) until three weeks after parturition (postpartum, PP). From the cross-sectional ventilation image the ventral to dorsal (V/D), left to right (L/R) ventilation distribution ratio and the relative ventilation in four horizontal regions of interest (ROI) placed symmetrically in the chest was analyzed. Antepartum V/D was 0.74 ± 0.09 on day -28 ± 3 (AP28) and decre...
Labelle AL, Metzler AG, Wilkie DA.Neoplasia, for which surgical excision is a frequent treatment, is the most common disease of the equine nictitating membrane. There is little long-term follow-up information available to the practitioner regarding the long-term effects of nictitating membrane excision on ocular health. No information is available to compare recurrence of primary neoplasia of the nictitating membrane after excision with local or general anaesthesia. Objective: To evaluate the long-term complications of nictitating membrane resection in horses; recurrence of neoplasia of the nictitating membrane when nictitatin...
Page AE, Stills HF, Chander Y, Gebhart CJ, Horohov DW.Lawsonia intracellularis is the causative agent of equine proliferative enteropathy (EPE), a disease for which no large-scale seroprevalence studies have been conducted. Objective: To validate and use an equine-specific enzyme-linked immunosorbent assay (ELISA) for L. intracellularis to determine the seroprevalence of L. intracellularis on numerous farms. Methods: An ELISA, in which purified antigen was used, was adapted from previous work in swine. A total of 337 Thoroughbreds from 25 central Kentucky farms were enrolled and monthly serum samples collected from August 2010 to January/February...
Bucca S, Carli A.Human chorionic gonadotropin (hCG) and dexamethasone have a role in the reproductive management protocols of mares susceptible to persistent mating-induced endometritis (PMIE). However, it is possible that there is interference between these 2 drugs. Objective: The objective of this retrospective study was to determine the efficacy of hCG to induce ovulation in mares treated with dexamethasone at breeding time. Methods: Medical records from 152 mares and 223 cycles were analysed. In 113 cycles, mares susceptible to PMIE were treated with 1500 iu hCG and a single dose of 50 mg dexamethasone, 11...
Auletta L, Lamagna F, Uccello V, Lamagna B, Pasolini MP.The equine small intestine can be affected by a variety of disorders that may require some form of bypass or anastomosis. Many suture patterns have been used in equine anastomoses to minimise post operative complications, which include leakage from the anastomosis site, stenosis and adhesions. Because of the critical condition of horses undergoing colic surgery, it is imperative this is performed as quickly as possible. Objective: To evaluate, in vitro, differences in the time of execution and leakage pressure between the Lembert single layer, Gambee and Lembert double layer suture patterns fo...
Hoogewijs M, Morrell J, Van Soom A, Govaere J, Johannisson A, Piepers S, De Schauwer C, De Kruif A, De Vliegher S.The increasing use of modern reproductive techniques in human medicine has led to a higher demand for isolation of motile sperm. Several of these isolation techniques have been adapted for veterinary use and can be applied for the selection of a superior sperm sample from stallion semen. Until recently a major disadvantage of such isolation techniques was the limitation in sperm volume that could be handled. Androcoll-E had been shown to be successful for processing large volumes of equine semen but there are few data to substantiate the potential beneficial effect of freezing an Androcoll-E s...
Christophersen MT, Tnibar A, Pihl TH, Andersen PH, Ekstrøm CT.There is a paucity of studies addressing sporting activity and horse owners' satisfaction after horses have undergone colic surgery. Objective: To determine 1) survival rate after colic surgery, 2) prevalence of horses returning to, or starting, sporting activities and 3) assess the owners' satisfaction regarding colic surgery. Methods: Cases that underwent exploratory celiotomy for colic between January 2005 and August 2010 were reviewed. All horses that had one or more celiotomies and were discharged after colic surgery were included in a telephone questionnaire survey. Only horses that surv...
Petzinger E.Pyrrolizidine alkaloids belong to a class of phytotoxins which are present in more than 6000 plant species. The disease seneciosis in farm animals represents the severe poisoning by pyrrolizidine alkaloids from plants of the genus Senecio. This form of poisoning has been known since the end of the 19th century in Germany, the USA, Canada and New Zealand, and is mainly caused by Senecio jacobaea and related Senecio spp. in farm animals, including poultry. Animal poisoning by pyrrolizidine alkaloids is of worldwide importance. In Germany poisoning of horses and cattle by Senecio jacobaea, which ...
Defontis M, Vaillancourt D, Grand FX.This prospective study aims to compare three different sampling techniques for the collection of endometrial cytological specimens in the mare: the guarded culture swab, the uterine cytobrush and the low volume uterine flush. Methods: The study population consisted of six healthy Standardbred mares in dioestrus. In each mare an acute endometritis was induced by performing a low- volume uterine flush 6days after ovulation using a sterile isotonic solution (lactated Ringer's solution or ViGro™ Complete Flush Solution). Two days after initiating inflammation, samples were collected from each ma...
Wobeser BK, Hill JE, Jackson ML, Kidney BA, Mayer MN, Townsend HG, Allen AL.Equine sarcoids are the most common tumor of horses. Bovine papillomavirus (BPV) has been suggested as the cause of sarcoids. Studies have shown that BPV is present in swabs or biopsies from nonsarcoid-bearing equine skin. Skin biopsies from a variety of different conditions and normal skin from horses with no reported history of sarcoids were examined by polymerase chain reaction (PCR) for the presence of BPV, which was found in all different types of skin conditions as well as normal skin. Forty-one out of 86 skin biopsies from horses without sarcoids were found to contain BPV DNA. Laser mic...
Hertsch B, Teschner D.Objective of the study was to investigate whether a correlation between rotation and/or sinking of the third phalanx (P3) and changes of horn growth on the hoof wall exists. Methods: In 117 hooves of euthanatized or slaughtered horses with chronic laminitis the rotating angle to palmar/plantar and medial/lateral and a sinking of P3 were assessed on radiographs. Defined distances were measured on the dorsal hoof wall as well as in the heel to assess the horn growth of a hoof. On the basis of saw cuts of the hooves, the course of the horn tubes was judged. Results: A rotation angle of approximat...
Dicht S, Del Chicca F, Fürst A.Ectopic teeth occur because of failure of the first branchial cleft to close during development and are found mostly in young horses. Such dentigerous cysts are often located at the base of the ear, forming a notable swelling with a fistula, as it was the case with the two year old Iceland mare «Runa». In order to confirm the diagnosis, x-ray images were taken, which is also necessary to locate the ectopic tooth correctly. While operating, the whole cystic membrane should be removed and it is important to prevent adjacent nerves and blood vessels from damage. Prognosis for complete healing a...
Hanlon DW, Firth EC.The objective of this study was to investigate the effects of intravaginal progesterone on the reproductive performance of transitional Thoroughbred mares on commercial stud farms. Two hundred twenty-seven (227) non-lactating transitional Thoroughbred mares aged between 4 and 18 y (mean 9.4 ± 3.2 y) located on three stud farms in the Waikato region of New Zealand were used in the study performed during four consecutive breeding seasons (2007-10). Mares were age-matched in pairs and either treated with an intravaginal progesterone releasing device (Cue-Mare, 1.72 g progesterone, 10% w/w) for u...
David F, Cadby J, Bosch G, Brama P, van Weeren R, van Schie H.Larger superficial digital flexor tendon (SDFT) injuries have a poorer prognosis than smaller lesions. During the inflammatory phase enlargement of the initial lesion is frequently noted, with biomechanical loading being recently proposed to play an important role. Objective: To evaluate the effect of lower limb cast immobilisation on tendon lesion propagation in an equine model of surgically induced SDFT injury. Methods: Core lesions were surgically induced in both front SDFTs of 6 young mature horses. At the end of surgery, one leg was randomly placed in a lower limb cast and the other leg (...
Leclere M, Magdesian KG, Cole CA, Szabo NJ, Ruby RE, Rhodes DM, Edman J, Vale A, Wilson WD, Tell LA.Azithromycin is widely used in foals but has not been studied in adult horses. The goals of this study were to determine the pharmacokinetic profile and to make a preliminary assessment of the safety of azithromycin in adult horses. Azithromycin was administered intravenously (5 mg/kg) and intragastrically (10 mg/kg) to six healthy mares in a crossover design. Serial plasma samples, blood neutrophils, and pulmonary macrophages were collected for the measurement of azithromycin concentrations. Azithromycin was also administered orally (10 mg/kg) once a day for 5 days to five healthy mares for p...
Menzies-Gow NJ, Knowles EJ, Rogers I, Rendle DI.Circulating adiponectin concentrations were lower in ponies with a history of endocrinopathic laminitis and in nonlaminitic ponies that subsequently developed laminitis. The assays used in these studies have been discontinued or are no longer valid. Objective: (1) to determine the validity of immunoturbidimetric (IT) and enzyme linkedimmunosorbent (ELISA) assays for equine total and high molecular weight (HMW) [adiponectin] measurement and (2) to investigate the association between [adiponectin] measured using these assays and endocrinopathic laminitis. Methods: Method validation and cohort st...
Tinling SP, Cardinet GH, Blythe LL, Cohen M, Vonderfecht SL.The structure of sarcocysts in a horse is presented. Light microscopic examination revealed that the maximum cyst dimensions were 136 X 990 micrometers and the cyst walls were striated and 1 to 3 micrometers thick. Electron microscopic examination revealed that the "cyst wall" was formed by villuslike protrusions of the parasitophorous vacuole's primary wall. A unique feature was the presence and arrangement of microtubules within the parasitophorous vacuole. Thirty-four to 55 microtubules extended from the apical tips and sides of each villus and passed through the ground matrix to form junct...
Marañón G, Manley W, Cayado P, García C, de la Muela MS, Vara E.Colic could be accompanied by changes in the morphology and physiology of organs and tissues, such as the intestine. This process might be, at least in part, due to the accumulation of oxidative damage induced by reactive oxygen (ROS) and reactive nitrogen species (RNS), secondary to intestinal ischemia. Glutathione (GSH), being the major intracellular thiol, provides protection against oxidative injury. The aim of this study was to investigate whether ischemia-induced intestinal injury could be related with alterations in GSH metabolism. Results: Ischemia induced a significant increase in lip...
Ellenberger MA, Kaeberle ML, Roth JA.A lymphocyte blastogenic assay was developed to serve as an in vitro correlate of cell-mediated immunity to Rhodococcus (Corynebacterium) equi (R equi) in the equine species. Lymphocytes obtained from a group of experimental ponies showed no response in cell culture to R equi heat extract or lysozyme extract antigens. Ponies were assigned to groups for experimental inoculation. Three ponies were inoculated subcutaneously with live R equi, 3 were given live R equi by intranasal and intratracheal routes, and 4 ponies were left untreated. Lymphocytes from all inoculated ponies had a mitogenic res...
Valentine BA.Gross and histopathologic evaluation of skeletal muscle was performed in 229 equids (217 horses, 8 ponies, 3 donkeys, and 1 mule) 1 year of age or older undergoing postmortem examination at Oregon State University in a 2.5-year period. Animals were evaluated for grossly evident muscle lesions, and muscle samples were fixed in formalin, processed routinely, and stained with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) for glycogen. Muscle lesions were detected in 149 animals (65%). Chronic myopathic change (excessive fiber size variation and internal nuclei) was evaluated in horses...
Ginther OJ, Gastal EL, Gastal MO, Checura CM, Beg MA.The effect of insulin-like growth factor-I (IGF-I) on the concentrations of follicular fluid factors during follicle deviation and the development of dominance was studied in mares in two experiments. Transvaginal ultrasound guidance was used for intrafollicular injection and subsequent sequential sampling of follicular fluid. Treatment involved a single injection of IGF-I into the second-largest follicle (F2) at the expected beginning of deviation (Hour 0) based on diameter (> or =20 mm) of the largest follicle (F1). Mares in IGF-I groups were given a dose of 500 microg (experiment 1) or 2...
Stokol T, Serpa PBS, Zahid MN, Brooks MB.Equid herpes virus type-1 (EHV-1) is a major pathogen of horses, causing abortion storms and outbreaks of herpes virus myeloencephalopathy. These clinical syndromes are partly attributed to ischemic injury from thrombosis in placental and spinal vessels. The mechanism of thrombosis in affected horses is unknown. We have previously shown that EHV-1 activates platelets through virus-associated tissue factor-initiated thrombin generation. Activated platelets participate in thrombus formation by providing a surface to localize coagulation factor complexes that amplify and propagate thrombin genera...
Green SL, Conlon PD, Mama K, Baird JD.The effects of hypoxia and azotaemia on the pharmacokinetics of amikacin were evaluated in 20 full-term neonatal critically ill foals which required 24-h supportive care, antibiotics and dextrose-supplemented polyionic fluids given intravenously, nasal insufflation with oxygen and nutritional supplementation. There was no association between sepsis score or survival and pharmacokinetic parameters. Concurrent hypoxia and azotaemia were associated with significantly decreased clearance and increased peak and trough serum concentrations of amikacin; however, peaks or troughs did not exceed toxic ...
Mainguy-Seers S, Bessonnat A, Picotte K, Lavoie JP.Inhaled corticosteroids are effective in the treatment of equine asthma. A recent study reported that nebulisation of injectable dexamethasone had low systemic bioavailability in healthy horses and could represent a cost-effective therapy for equine inflammatory lung diseases. Objective: To determine the effects of dexamethasone nebulisation on lung function in severe asthmatic horses. It was hypothesised that dexamethasone administered by nebulisation would be more effective than the same dose administered orally. Methods: Randomised blinded experimental study in severe asthmatic horses. Meth...
McMullen RJ, Davidson MG, Gilger BC.To determine the effects of tropicamide 1% on the refractive state of the adult equine globe and identify the most appropriate time period (in relation to mydriasis) to perform streak retinoscopy. Methods: Eight university-owned mares of various ages and breeds. Methods: Topical tropicamide 1% was applied to one randomly selected eye from each of the horses to induce mydriasis and cycloplegia. The contralateral eyes served as controls. Streak retinoscopy and pupillometry were performed prior to, and every 5 min after tropicamide 1% installation for 90 min. Results: All values are expressed as ...
Pamornsakda T, Pojprasath T, Suwimonteerabutr J, Tharasanit T.Equine epididymal sperm are known to be severely sensitive to cryopreservation, in terms of sperm quality and pregnancy rate. The objective of this study was to examine the effects of cholesterol loaded cyclodextrins (CLCs) on the quality of stallion epididymal sperm during cryopreservation. In experiment I, sperm were treated with different concentrations of CLCs: (1) 0mg (control), (2) 1.5mg, (3) 3mg, and (4) 6 mg per 120 × 10(6) sperm. The sperm viability and amount of cholesterol were determined at 15, 30 and 45 min after CLC treatment using viability markers (Ethidium homodimer-1 and Cal...
Zhou T, Yuan XF, Hou SH, Tu YB, Peng JM, Wen JX, Qiu HJ, Wu DL, Chen HC, Wang XJ, Tong GZ.In the early 1970s, the Chinese Equine Infectious Anemia Virus (EIAV) vaccine, EIAV(DLA), was developed through successive passages of a wild-type virulent virus (EIAV(L)) in donkeys in vivo and then in donkey macrophages in vitro. EIAV attenuation and cell tropism adaptation are associated with changes in both envelope and long terminal repeat (LTR). However, specific LTR changes during Chinese EIAV attenuation have not been demonstrated. In this study, we compared LTR sequences from both virulent and attenuated EIAV strains and documented the diversities of LTR sequence from in vivo and in v...
Firth EC, Rogers CW, Jopson N.The response of equine bone to training has not been quantified in racetrack trained horses, only in treadmill exercised horses. Seven two-year-old thoroughbred fillies were trained on sand and grass at a racetrack, in a typical New Zealand flatrace training regime. The horses were exercised 6 days per week for up to 13 weeks. During the day the horses were confined in 4 x 4m sand yards, and were stalled at night. Another 7 fillies of the same age were allowed free exercise in grass yards. The bones of the animals were available after the 13 week experimental period, and were examined using a ...
Ottley ML, Dallemagne C, Moorhouse DE.Investigations were conducted on the taxonomy, distribution in the carcase, pathology and transmission of Onchocerca spp. in equids from Queensland and the Northern Territory. Examination of small groups of horses and ponies revealed high infection rates with O. cervicalis, while lesser numbers were infected with O. gutturosa. O. reticulata was not found. Neither of the Australian species is likely to be of economic importance to the horsemeat industry. The findings support the belief that O. cervicalis is a pre-disposing factor in the aetiology of equine nuchal disease, most commonly seen cli...
Bolt DM, Burba DJ, Hubert JD, Pettifer GR, Hosgood GL.Extracorporeal shock wave therapy is becoming increasingly used in equine practice to treat musculoskeletal disorders. Although the exact effects of extracorporeal shock waves on tissues still need to be elucidated, transient cutaneous analgesia has been observed within treated areas in humans and horses. The purpose of this study was to determine the onset, magnitude, and duration of cutaneous analgesia after non-focused extracorporeal shock wave (ESW) application by comparing the limb withdrawal reflex latency (LWRL) in treated and untreated areas on the metacarpus of horses, using a focused...
Varner DD, Blanchard TL, Love CL, Garcia MC, Kenney RM.Two experiments were conducted to examine the effects of cooling rate and storage temperature on motility parameters of stallion spermatozoa. In Experiment 1, specific cooling rates to be used in Experiment 2 were established. In Experiment 2, three ejaculates from each of two stallions were diluted to 25 x 10(6) sperm/ml with 37 degrees C nonfat dry skim milk-glucose-penicillin-streptomycin seminal extender, then assigned to one of five treatments: 1) storage at 37 degrees C, 2) storage at 25 degrees C, 3) slow cooling rate to and storage at 4 degrees C, 4) moderate cooling rate to and storag...
Sanders RE, Kearney CM, Buckley CT, Jenner F, Brama PA.To evaluate knot security for 3 knot types created in 3 commonly used 5 metric suture materials incubated in physiological and pathological fluids. Methods: In vitro mechanical study. Methods: Knotted suture loops (n = 5/group). Methods: Loops of 3 different suture materials (glycolide/lactide copolymer; polyglactin 910; polydioxanone) were created around a 20 mm rod using 3 knot types (square [SQ], surgeon's [SK], and triple knot [TK]) and were tested to failure in distraction (6 mm/min) after tying (day 0) and after being incubated for 14 and 28 days in phosphate buffered saline (PBS...
Zielinski J, Mevissen M.Testosterone hydroxylation was investigated in human, canine and equine liver microsomes and in human and canine single CYPs. The contribution of the CYP families 1, 2 and 3 was studied using chemical inhibitors. Testosterone metabolites were analyzed by HPLC. The metabolites androstenedione, 6β- and 11β-hydroxytestosterone were found in microsomes of all species, but the pattern of metabolites varied within species. Androstenedione was more prominent in the animal species, and an increase over time was seen in equines. Testosterone hydroxylation was predominantly catalyzed by the CYP3A subf...
Suagee JK, Corl BA, Swyers KL, Smith TL, Flinn CD, Geor RJ.High glycaemic feeds are associated with the development of insulin resistance in horses. However, studies that evaluated the effect of high glycaemic feeds used horses that either ranged in body condition from lean to obese or were fed to increase body condition over a period of months; thus, the ability of high glycaemic feeds to induce insulin resistance in lean horses has not been determined. This study evaluated the insulin sensitivity of 18 lean horses fed a 10% (LO; n = 6), 20% (MED; n = 6) or 60% (HI; n = 6) non-structural carbohydrate complementary feed for 90 days. Alth...
Joré C, Loup B, Garcia P, Paris AC, Popot MA, Audran M, Bonnaire Y, Varlet-Marie E, Bailly-Chouriberry L.Erythropoiesis Stimulating Agents (ESAs) were developed for therapeutic purposes to stimulate red blood cell (RBC) production. Consequently, tissue oxygenation is enhanced as athlete's endurance and ESAs misuse now benefits doping. Our hypothesis is that most of ESAs should have similar mechanisms and thus have the same effects on metabolism. Studying the metabolome variations could allow suspecting the use of any ESAs with a single method by targeting their effects. In this objective, a metabolomic study was carried out on 3 thoroughbred horses with a single administration of 4.2μg/kg of Mir...
Rotchanapreeda T, Sae-Chew P, Lohnoo T, Yingyong W, Rujirawat T, Kumsang Y, Payattikul P, Jaturapaktrarak C, Intaramat A, Pathomsakulwong W....Pythiosis, a life-threatening disease caused by , has been increasingly diagnosed worldwide. A recently developed immunochromatographic test (ICT) enables the rapid diagnosis of pythiosis. During the 3-year clinical implementation of ICT in Thailand, we collected the laboratory reports of 38 animals with suspected pythiosis and detected ICT false-positive results in three horses and a dog with basidiobolomycosis. and cause infections with indistinguishable clinical and microscopic features. This study investigated cross-reactive antibodies by probing and crude extracts and cell-free synthe...
Rumbaugh GE, Smith BP, Carlson GP.internal abdominal abscesses in 25 horses, including 8 horses that died or were euthanatized, were found to be caused by Streptococcus equi, Streptococcus zooepidemicus, or Corynebacterium pseudotuberculosis. Breed or sex predilection was not found. Although horses of all ages were affected, those under 5 years of age were more commonly affected. Nearly all of the horses had a history of respiratory catarrh or lymphadenitis. Horses with internal abdominal abscesses also had intermittent, prolonged colic or chronic weight loss. Most horses had increased rectal temperature, increased heart and r...
Torbert BJ, Kramer BS, Klei TR.A controlled test was used in ponies to compare the antiparasitic efficacy of ivermectin (22,23-dihydro-avermectin B1) in an injectable micelle solution administered IM with the efficacy of the same drug in an oral paste formulation. Parasite infections were naturally acquired in southern Louisiana. The drug was tested in both formulations at a dosage level of 0.2 mg/kg of body weight. Ivermectin in both formulations tested had an efficacy greater than 98% against Gasterophilus intestinalis and G nasalis larvae. Trichostrongylus axei, Habronema spp, Strongylus vulgaris, S. edentatus, and speci...
Pinchbeck GL, Clegg PD, Proudman CJ, Morgan KL, French NP.Between March 1, 2000 and August 31, 2001, a case-control study was conducted on 12 racecourses in England and Wales to identify and quantify the risk factors associated with horse falls in hurdle races. The cases and controls were defined so that variables relating to the horse, the jockey, the race and racecourse, and the jump could be considered. The cases were defined as a jumping effort at a hurdle flight that resulted in a fall, and the controls were defined as a successful jump over a hurdle at any of the 12 racecourses within 14 days before or after the case fall. Conditional logistic ...
Wijnberg ID, Sleutjens J, Van Der Kolk JH, Back W.There has been growing interest in training techniques with respect to the head and neck position (HNP) of the equine athlete. Little is known about the influence of HNP on neuromuscular transmission in neck muscles. Objective: To test the hypothesis that different HNPs have effect on single fibre (SF), quantitative electromyographic (QEMG) examination and muscle enzyme activity directly after moderate exercise. Methods: Seven Warmblood horses were studied using a standard exercise protocol in 5 HNPs: HNP1: unrestrained; HNP2: neck raised; bridge of nose around the vertical; HNP4: neck lowered...
