Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Timoney JF, Mukhtar MM.The group C streptococci are the most commonly isolated bacteria from disease states in the horse. Important virulence factors of S. equi and S. zooepidemicus are the hyaluronic acid capsule and the antiphagocytic fibrillar M protein located on the surface of the cell wall and extending into and through the capsule. The hyaluronic acid capsule is non-antigenic and so is not involved in protective immunity. The M protein, a superantigen, elicits very strong B and T cell responses that may result in protective immunity mediated by opsonic antibodies in plasma and by locally synthesized IgG and I...
Boening KJ, Leendertse IP.The medical records of pregnant mares over a 3-year period were reviewed. In all cases persistent pain or progressive abdominal distension were the main reason for referral. The overall survival rate for the 115 mares treated for colic was 73.9% (85 cases). The abortion rate was 20.5% in surgical patients (34 cases), 40% (5 cases) for mares with uterine torsions and 10.8% (46 cases) after medical treatment. The total abortion rate was 16.4%. Clinical evidence of endotoxaemia was, except for 1 mare, present in all the aborting mares after colic treatment. Anaesthesia did not appear to be a prob...
Golenz MR, Carlson GP, Madigan JE, Craychee T.Six normal foals between the ages of 2 and 7 days were used in this study to develop a technique for intraosseous infusion in equine neonates. A 14-gauge 1/2-inch needle was placed intraosseously in the right proximal medial one-third aspect of the radius and tibia of each foal. A maximum of 1 L of isotonic fluids was administered intraosseously at these sites. Radiographs were taken at the time of intraosseous needle placement, and at days 10, 30, and 60 following the procedure. The mean time for needle placement was 33 seconds for the tibia and 63 seconds for the radius. The mean fluid flow ...
Dabareiner RM, Sullins KE, White NA.The clinical and radiographic progression, and arthroscopic findings for nine young horses (< 1 year of age) with femoropatellar osteochondrosis (OCD) are presented. Horses had a 2 to 12 week history of bilateral (8 horses) or unilateral (1 horse) hindlimb lameness. The most consistent clinical signs included femoropatellar joint distention and bilateral hindlimb lameness. At the onset of clinical signs, radiographic lesions were not present (4 horses) or subtle (5 horses), but were easily identified on radiographs taken 4 to 24 weeks later. Arthroscopic surgery was delayed until radiograph...
Choi YH, Hochi S, Braun J, Sato K, Oguri N.The aim of this study was to examine 2 techniques for oocyte recovery from equine ovaries at slaughter: by aspiration of follicles and by additional slicing of ovaries. The morphology and nuclear configuration of oocytes recovered with either technique, and the time course of nuclear maturation during in vitro maturation were evaluated. Recovery rates were 1.75 and 4.14 oocytes per ovary for aspiration and slicing (total 145 and 344 oocytes from 83 ovaries), respectively. The oocytes were classified according to their cumulus/ooplasm morphology into 4 groups: compact/circular(A), compact/semic...
Hoffman AM, Viel L, Staempfli HR, Muckle CA, Yager JA.One indication for referral of horses to veterinary hospitals is for diagnosis of the microbiologic cause of pneumonia, particularly when the initial treatment fails. Although endoscopic methods have long been available for microbiologic sample collection, accuracy of these methods under these conditions have not been studied in detail. We compared the bacteria isolated from samples obtained by bronchoalveolar lavage (BAL) with those obtained by protected catheter brush (PCB) from foals with unilateral pneumonia induced by inoculation with Klebsiella pneumoniae. As part of previously described...
Epe C, Ising-Volmer S, Stoye M.The results of the coproscopical examinations in horses, dogs, cats and hedgehogs between 1984 and 1991 are presented. In 9192 samples from horses 55.5% stages of strongylids, 4.0% of Parascaris equorum, 2.2% of anoplocephalids, 1.6% Strongyloides westeri, 0.7% of Oxyuris equi, 0.6% of Eimeria leuckarti, 0.2% of Fasciola hepatica and 0.04% of Dictyocaulus arnfieldi were found. In 48.0% of the 46 samples from donkeys eggs from strongylids were detected, in 17.4% larvae from Dictyocaulus arnfieldi, in 2.2% eggs from Strongyloides westeri, Parascaris equorum and oocysts from Eimeria leuckarti, re...
Oriol JG, Sharom FJ, Betteridge KJ.The embryonic capsule, which covers the equine blastocyst after it loses its zona pellucida, is composed of mucin-like glycoproteins. In the present study, we investigated both macroscopic and molecular changes in the capsule during development. The weight of the capsule increased from day 11-12 of pregnancy and reached a maximum at about day 18, coinciding with the time during which the conceptus migrates extensively throughout the uterus. The sialic acid content of the capsule declined markedly from about day 16, the time of conceptus 'fixation' in the uterus, which suggests a unique develop...
Lopez-Plana C, Sautet JY, Ruberte J.Three adductor muscles of the larynx, the cricoarytenoideus lateralis (CAL), the arytenoideus transversus (AT) and the ventricularis (Ve), from 36 horses were examined histologically. The neurogenic changes seen in each muscle were evaluated qualitatively. In addition, in 6 horses with clinical and subclinical signs of neurogenic atrophy, measurements of muscle fibre area were performed. Neurogenic changes observed in the Ve were less than in CAL and AT. Measurements of muscle fibre area also demonstrated that CAL and AT showed a wider range of pathological changes than did Ve. The results sho...
Gillis CL, Meagher DM, Pool RR, Stover SM, Craychee TJ, Willits N.The forelimb superficial digital flexor (SDF) tendons of 6 Thoroughbreds were examined clinically and ultrasonographically during the first 4 months of race training. Sonograms were interpreted clinically and by use of computer-aided analysis. Tendon tissue from all horses was examined histologically at the end of the study. Computer-aided analysis of sonograms of the SDF tendons revealed trends toward an increase in mean cross-sectional area and a decrease in mean echogenicity over time with training. An inverse relation was found between increase in cross-sectional area and decrease in mean ...
Lunn DP, Cuddon PA, Shaftoe S, Archer RM.In an investigation of 2 closely related Miniature Horses with a history of excessive sleepiness, depression and episodes of collapse, a diagnosis of narcolepsy was made on the basis of neurological examination and pharmacological testing. Further investigations included electroencephalographic examination (EEG), and analysis of protein content, cell count and monoamine metabolite concentrations of lumbosacral cerebrospinal fluid (CSF). There were no abnormalities noted in the EEGs, and no consistent changes in CSF neurotransmitter metabolites in the narcoleptic horses when compared with 3 nor...
Steffey EP, Giri SN, Dunlop CI, Cullen LK, Hodgson DS, Willits N.Six healthy horses were anaesthetised with halothane (1.2 times the horse minimal alveolar concentration) in oxygen for more than 12 hours. Serum bilirubin, aspartate aminotransferase, alkaline phosphatase and L-iditol dehydrogenase values were significantly (P < 0.05) increased for up to nine days after anaesthesia. These changes suggest an anaesthesia related liver dysfunction. Creatine kinase increased to an average of more than 1400 IU litre-1 24 hours after anaesthesia and this change is indicative of muscle cell disruption. Renal-associated biochemical results, (that is serum creatinine ...
Art T, Lekeux P.The effects of training and detraining on ventilation during a standardised exercise test were investigated. Ten healthy Thoroughbred horses underwent 5 standardised treadmill exercise tests (SET): SET1, at the start of the experimental period; SET2, after 3 weeks acclimatisation; SET3, after 3 week of aerobic training; SET4 after 3 weeks of anaerobic (i.e. interval) training; and SET5, after 3 weeks of detraining. The SETs were carried out in an air-conditioned laboratory on a treadmill inclined at 6 degrees. Respiratory airflow, tidal volume (VT), respiratory frequency (RF) and expired minut...
Foerner JJ, Ringle MJ, Junkins DS, Fischer AT, MacHarg MA, Phillips TN.A 7-year-old Thoroughbred mare underwent exploratory celiotomy for diagnosis and treatment of colic. An irreducible herniation of the large colon through the epiploic foramen was found. To reduce the hernia, the pelvic flexure was transected and the ends of the large colon were closed. The intercolonic mesentery was divided, and unaffected left ventral colon was moved into the epiploic foramen, providing sufficient space so that affected left dorsal colon could be reduced. The affected left ventral colon was then reduced and the diseased portion of both colons was resected. The colons were res...
McKane SA, Canfield PJ, Rose RJ.Sixty-two Thoroughbred horses aged between 1 and 7 years in training in Sydney had bronchoalveolar lavage (BAL) samples collected for cytological examination. All horses, except the yearlings and those with a cough, had raced at the time of the examination and the trainers reported satisfactory performance. Free erythrocytes were found in 73% of samples and haemosiderophages in 90% of the samples, indicating immediate or past occurrences of exercise-induced pulmonary haemorrhage (EIPH). Bronchoalveolar fluid from the yearlings contained significantly less (P < 0.05) erythrocytes and haemosi...
Troedsson MH, Wiström AO, Liu IK, Ing M, Pascoe J, Thurmond M.A method for interpreting and analysing electromyographic (EMG) data of myometrial electrical activity was established. This method was used to study EMG activity in the uterus during the various stages of the oestrus cycle in mares. Recordings were analysed from four pairs of electrodes that were surgically implanted in the myometrium of four reproductively sound mares. The electrodes were placed at the tip, middle and base of the left horn and in the uterine body. Electrical activity was monitored by a polygraph. Data were transformed to a digitized form and statistically analysed. Myometria...
Maxson AD, Giger U, Sweeney CR, Tomasic M, Saik JE, Donawick WJ, Cothran EG.Anemia that was secondary to ovarian hemorrhage in a 4-year-old miniature horse mare was treated prior to laparotomy with polymerized ultrapurified bovine hemoglobin (PUBH). Two previous whole-blood transfusions had resulted in acute transfusion reaction, and a suitable blood donor could not be found among 9 horses, necessitating use of the blood substitute. Subsequent blood typing revealed the mare to be Aa-negative, with allo-antibodies against Aa in serum. Serious adverse reactions were not observed after infusion of PUBH, and the mare recovered. Although the safety and efficacy of using PU...
Magnarelli LA, Anderson JF.In a retrospective study, indirect fluorescent-antibody staining methods were used to detect immunoglobulins to Ehrlichia canis and Ehrlichia risticii in canine and equine sera that had originally been analyzed for antibodies to Borrelia burgdorferi. Analyses of 60 dog serum specimens collected in Connecticut and New York State during 1986 revealed antibodies to E. canis in 7 (11.7%) specimens; titration endpoints ranged from 1:40 to 1:320. Three of these dogs had anemia. Of the 187 equine serum specimens obtained in Connecticut during 1985 and analyzed by indirect fluorescent-antibody stainin...
Freeman KP, Roszel JF, McClure JM, Mannsman R, Patton PE, Naile S.Thirty-six transtracheal washing (TTW) and 12 bronchoalveolar lavage (BAL) specimens collected in clinical practice from horses with and without respiratory disease were reviewed. Cytological features were considered in accordance with the presenting complaint, clinical signs, clinical diagnoses, microbiological, radiographic and/or endoscopic findings, therapy, and response to therapy. The trichrome-stained TTW and BAL specimens were useful in interpreting the results of concurrent microbiological cultures, and determining whether a condition was present based on occurrence of typical cytolog...
Regodon S, Franco A, Lignereux Y, Redondo E.A technique is described for catheterisation of the ventricular recess within the olfactory bulb of the horse. Twelve adult horses were used. The olfactory recess is in the frontal region, 42 +/- 3 mm below the skin, on the line joining the supraorbital foramina, and approximately 18 +/- 2 mm from the midline. The approach is relatively easy under normal experimental conditions.
Yurdaydin N, Tekin N, Gülyüz F, Aksu A, Klug E.An Arab broodmare herd of 30 mares age ranging from 4 to 12 years was grouped into 3 groups (group A, B, C) with 10 mares each and exposed to three different methods of cycle synchronisation. Group A mares received two PGF2 alpha injections 14 days apart. Group B mares got additionally 2,500 IU of hCG 5 days after second prostaglandin application. Group C consisted of mares which had foaled in a synchrony of one week and got a PGF2 alpha injection 3 weeks after parturition. All the mares responding to synchronisation were inseminated closely to ovulation detected by serial rectal palpations wi...
Ruggles AJ, Ross MW, Freeman DE.Sixteen horses with suspected paranasal sinus disease had endoscopic examination of the paranasal sinuses with a 4.0 mm arthroscope either while standing and sedated (14 horses) or under general anesthesia (two horses). Endoscopic diagnosis included sinusitis (four horses), sinus cyst (three horses), hemorrhage (three horses), neoplasia (three horses), and tooth root abnormalities (two horses). No abnormalities were detected in one horse. Endoscopic findings concurred with the radiographic findings in 13 horses (81%). Samples of sinus contents for bacteriologic (eight horses) and histologic ex...
van den Belt AJ, Keg PR, Kik KJ, Barneveld A.An in vitro study was carried out to define the correlation between the dose and distribution of intratendinous fluid injections in the different flexor tendons/ligaments of the palmar/plantar, metacarpal/metatarsal region of the horse. Injection of 0.1-0.2 ml resulted in a local intratendinous fluid depot showing minimal abaxial spreading and more extensive proximodistal expansion. If 0.3-0.5 ml was injected the abaxial spreading remained minimal but the proximodistal expansion increased significantly, the depots in the axial proximal, mid and distal region flowing together. Also minimal peri...
Wright IM.The clinical features are reported from 118 horses (mean age 9.2 years) which were diagnosed as suffering from navicular disease using predetermined criteria. The animals were used for a variety of purposes and had been lame for periods between 1 and 72 months. The majority of cases (84.7%) had been treated using various techniques before evaluation. The severity of lameness was related to the duration of clinical signs: 78% of horses were bilaterally affected but there was no left:right limb predominance. Broken foot/pastern axes were recorded in 75% of horses while 45% also exhibited mediola...
Bowker RM, Brewer AM, Vex KB, Guida LA, Linder KE, Sonea IM, Stinson AW.Two types of sensory receptors were located in the equine foot, using anatomic techniques. Histologic examination of stained hoof sections revealed lamellated corpuscles in the hoof dermis, which had many of the morphologic characteristics of Pacinian corpuscles. These sensory receptors were restricted to the palmar (caudal) aspects of the solar dermis of the heel. A second type of receptor was detected by use of immunocytochemistry, indicating apparently naked nerve endings containing the neuropeptide calcitonin gene-related peptide-like immunoreactivity in skin, solar dermal tubules, and the...
Wright IM.The 118 horses diagnosed as suffering from navicular disease by prospective criteria were treated by desmotomy of the ligamenta sesamoidea collateralia (navicular suspensory desmotomy). Three techniques were used and a standard post-operative programme was followed with clinical and radiological evaluations at 6-monthly intervals for periods of 6-36 months after surgery. At 6 and 36 months after treatment, 76% and 42.9% of horses were sound respectively. The clinical features of age, period of lameness, severity of lameness and angular limb deformities adversely affected response to surgery. T...
Todhunter RJ, Minor RR, Wootton JA, Krook L, Burton-Wurster N, Lust G.Our aim was to determine if mild to moderate postoperative exercise and intra-articular polysulfated glycosaminoglycan result in improved repair of large, experimentally induced osteochondral defects in a weight-bearing surface of equine joints. Arthroscopic debridement was used to produce full-thickness defects in a weight-bearing area of the radial carpal bones in 18 ponies. The ponies were randomly assigned to two groups balanced for age: nine animals in the exercise and nine in the no exercise group. Six ponies in each group were medicated weekly for 5 weeks with an intra-articular injecti...
Salvioli G, Gaetti E, Panini R, Lugli R, Pradelli JM.To evaluate why hemolysis of red blood cells (RBC) by bile acids varies in different mammalian species, we determined the mean corpuscular volume (MCV), lipid content and the concentrations of the conjugates of deoxycholate and of NaCl inducing 50% hemolysis of RBC from healthy humans, pigs, horses, cows, sheep and jaundiced humans. A volume of 0.05 mL of washed RBC at 1% hematocrit, which has the same lipid content but different phospholipid composition and number of erythrocytes (owing to the variable MCV), was incubated in taurodeoxycholate (TDC) solution (0-5 mM) to determine the TDC conce...
diBella G, Scandariato G, Suriano O, Rizzo A.The dependence of blood oxygen affinity and the Bohr effect on the concentration of 2,3-diphosphoglycerate (DPG) in erythrocytes was investigated in 24 trotter horses and 24 healthy men. The oxygen tension at half saturation and standard conditions (P50st at pH 7.4, PCO2(40) mmHg and 37 degrees C) and the carbon dioxide or fixed-acid-induced Bohr effect (dlogP50/dpH) were determined. Samples of fresh blood and blood depleted of or enriched with DPG were studied. In the absence of measurable DPG, the equine and human blood had similar mean (SD) values of P50st (16.6 [0.6] and 16.2 [0.7] mmHg, r...
Cian F, Whiteoak S, Stewart J.A 12-year-old British Warmblood mare was examined by the referring veterinarian for evaluation of a cutaneous lesion on the dorsal thorax to the right of the midline. Cytologic examination of fine-needle aspirates from the mass was supportive of a giant cell tumor of soft parts (GCTSP). Laser surgical excision and postoperative methyl aminolevulinate (MAL) photodynamic therapy (PDT) were performed. Histologic examination of the mass confirmed the cytologic diagnosis. At 8 months from surgery, no evidence of recurrence has been observed. Giant cell tumors of soft parts are rare cutaneous neopla...
Muir WW, Sams RA, Huffman R.The acute behavioral cardiopulmonary and pharmacokinetic effects of propoxyphene hydrochloride were studied in seven adult horses. Each horse was given three different dosages of propoxyphene (0.5, 1.0, 2.2 mg/kg) IV. Fourteen days was allotted between each drug administration. The lower IV dosages of propoxyphene (0.5, 1.0 mg/kg) resulted in no changes in indices of cardiopulmonary function. Four horses demonstrated a transient period of muscle fasciculations when given 0.5 mg of propoxyphene/kg. Horses given 1.0 mg/kg demonstrated a brief period of euphoria, ataxia, and muscle fasciculations...
Kirkland PD.During the 2007 equine influenza (EI) outbreak in Australia, diagnostic laboratories and the use of appropriate tests played a pivotal role in the response to the crisis. This role began with the detection of EI virus in New South Wales (NSW) on the evening of 24 August 2007 and culminated in providing the final 'proof of freedom' from EI in March 2008. The tests that were used during the EI response were able to provide results quickly, and with high sensitivity and specificity. This section of the supplement describes the roles and functions of the Australian laboratories; tests used and the...
Sojka JE, Johnson MA, Bottoms GD.This study was conducted to investigate the effect of starting time on dexamethasone suppression test results in horses. Eight adult horses were used throughout the trial. Baseline cortisol levels were established by collecting cortisol levels twice daily, at 8:00 A.M. and 8:00 P.M. for 4 consecutive days. Morning baseline cortisol levels were 46.3 +/- 5.94 ng/ml, and evening baseline cortisol levels were 32.8 +/- 5.59 ng/ml. Although lower, the evening cortisol levels were not statistically different (P = 0.154) from the morning levels. Dexamethasone suppression tests initiated at either 9:00...
Moorman VJ, Reiser RF, Peterson ML, McIlwraith CW, Kawcak CE.To determine kinematic changes to the hoof of horses at a trot after induction of unilateral, weight-bearing forelimb lameness and to determine whether hoof kinematics return to prelameness values after perineural anesthesia. Methods: 6 clinically normal Quarter Horses. Methods: For each horse, a sole-pressure model was used to induce 3 grades (grades 1, 2, and 3) of lameness in the right forelimb, after which perineural anesthesia was administered to alleviate lameness. Optical kinematics were obtained for both forelimbs with the horse trotting before (baseline) and after induction of each gr...
Hemberg E, Einarsson S, Jones B, Mikko S.The objective of this study was to investigate the presence and origin of polymorphonuclear leucocytes (PMNLs) in the amniotic fluid of mares giving birth to healthy foals. Material from 25 mares was included. Amniotic fluid was collected during parturition before breakage of the amniotic vesicle. Manual microscopic cytologic evaluation was made on cytospin preparations after staining. PMNLs were found in all amniotic samples examined. The genomic DNA was extracted from 12 of the amniotic fluid samples and was genotyped. The results indicate that the PMNLs originate from the foetus.
Waelchli RO, Corboz L, Doebeli M.To investigate the vulvovestibular contamination of endometrial culture swabs in the mare, a liquid culture of a streptomycin-resistant strain of Escherichia coli was applied to the vulvovestibular area of mares and used as a marker of contamination of endometrial culture swabs. Prior to taking endometrial swabs, the perineal area was washed with soap, rinsed with water, and dried. Endometrial culture swabs were taken from mares that were in anestrus or diestrus and from mares that were in estrus. When a manual transvaginal swabbing technique was used, 22 of 24 endometrial swab specimens from ...
Segabinazzi LGTM, Landers M, Kent A, Peterson E, Gilbert R, French H.Due to the limited literature available evaluating doses of Prostaglandin F2α in donkeys, doses for horses have been extrapolated and used as guidelines. This study aimed to assess the efficacy and side effects of four different cloprostenol sodium and dinoprost tromethamine doses to induce luteolysis in jennies. Sixty-three cycles of seven Jennies (nine cycles per jenny) were used in this study. Seven days after ovulation, jennies randomly received one of the treatments in a crossover design as follows: Control, no treatment was administered; C1, 250 µg of cloprostenol sodium (CS, Estrumate...
Symons JE, Fyhrie DP, Hawkins DA, Upadhyaya SK, Stover SM.Race surfaces have been associated with the incidence of racehorse musculoskeletal injury, the leading cause of racehorse attrition. Optimal race surface mechanical behaviors that minimize injury risk are unknown. Computational models are an economical method to determine optimal mechanical behaviors. Previously developed equine musculoskeletal models utilized ground reaction floor models designed to simulate a stiff, smooth floor appropriate for a human gait laboratory. Our objective was to develop a computational race surface model (two force-displacement functions, one linear and one nonlin...
Lawson A, Pinchbeck G.When planning to conduct research, thorough consideration of the study design is essential to enable valid results and purposeful conclusions. A good study design will provide a strong basis for robust conclusions that can contribute to the evidence base. Conversely, a poor study design may unintentionally lead to invalid conclusions with inappropriate claims of the clinical importance. The purpose of this article is to review important aspects of observational study design, with an emphasis on observational clinical research. The value of an observational study can be manifold and the benefit...
Hochi S, Fujimoto T, Oguri N.Viability following vitrification of equine blastocysts with different sizes was investigated in vitro. Twenty-four blastocysts were classified into three groups according to their diameters ( 300 microns; n = 8 each). The solution used for vitrification was defined as EFS and contained 40% ethylene glycol, 18% Ficoll and 0.3 M sucrose in modified-phosphate-buffered saline (m-PBS). During pretreatment with 20% ethylene glycol in m-PBS for 20 min, the larger blastocysts responded to the osmotic pressure caused by 20% ethylene glycol more slowly than the smaller blastocysts. Single blastocysts w...
Ehrlich PJ, Seeherman HJ, O'Callaghan MW, Dohoo IR, Brimacombe M.To determine anatomic patterns and clinical importance of increased radiopharmaceutical uptake in bones of horses used for show jumping, hunting, and eventing. Methods: Retrospective study. Methods: 141 horses evaluated because of lameness. Methods: Medical records were reviewed, and information on results of physical examination, radiography, and scintigraphy were obtained. Scintigrams were evaluated to identify areas of increased radio-pharmaceutical uptake. Results: 834 areas of increased radiopharmaceutical uptake were identified. Scintigraphy of the vertebral column was performed in 78 ho...
Kaiser A, Meier HP, Doherr MG, Perler L, Zanoni R, Gerber V.Since 1991, no cases of Equine Infectious Anemia (EIA) have been reported in Switzerland. Risk factors for introduction of the virus into Switzerland are still present or have even increased as frequent inapparent infections, large numbers of imported horses, (since 2003) absence of compulsory testing prior to importation, EIA cases in surrounding Europe, possible illegal importation of horses, frequent short-term stays, poor knowledge of the disease among horse owners and even veterinarians. The aim of this study was to provide evidence of freedom from EIA in imported and domestic horses in S...
Powell DG.Examples of equine disease surveillance at the local, regional, national and international level are discussed in this article. Reporting systems at each level are also considered, and the increasing importance of laboratory confirmed diagnoses is emphasized. The need to develop national disease reporting systems is addressed, particularly with respect to conforming to international trading standards.
Bedford SJ, McDonnell SM.To evaluate the effects of trimethoprim-sulfamethoxazole and pyrimethamine treatment on various measures of reproductive function in healthy pony stallions. Methods: Randomized complete block study. Methods: 12 healthy, mature pony stallions. Methods: Stallions were assigned to treatment and control groups balanced for age and various characteristics of reproductive function. The treated group received trimethoprim-sulfamethoxazole and pyrimethamine for 90 days during summer and fall; the control group was not treated. Semen characteristics, sexual behavior, testicular volume, and sperm produc...
Dill SG, Simoncini DC, Bolton GR, Rendano VT, Crissman JW, King JM, Tennant BC.During a period of 18 months, between July 1978 and January 1980, 4 adult horses were referred to the New York State College of Veterinary Medicine with evidence of congestive heart failure. Characteristic clinical abnormalities included marked muffling of heart sounds, tachycardia, jugular vein distention, and peripheral edema. Treatment with antibiotics, diuretics, and anti-inflammatory drugs was unsuccessful, and all four died or were euthanatized and necropsied. At necropsy, there was marked distention of the pericardial sac with fluid, and thick layers of fibrin were deposited uniformly o...
Ginther OJ, Beg MA.The temporal relationships between a pulse of 13,14-dihydro-15-keto-PGF(2alpha) (PGFM) and the concentrations of circulating hormones during the luteolytic period were studied for 11 pulses in 11 mares (Equus caballus) using samples collected hourly. Mean PGFM pulses encompassed 4h before to 4h after the peak, and hormone data were normalized to the PGFM peak (Hour 0). Concentration of progesterone decreased (P < 0.05) between Hours -4 and -3 and continued to decrease linearly throughout the PGFM pulse. The concentrations of cortisol and prolactin increased (P < 0.004) during Hours -4 to...
DelVento VR, Amann RP, Trotter GW, Veeramachaneni DN, Squires EL.A sample of testicular parenchymal tissue, approximately 2 x 7 x 7 mm, was aseptically removed from 1 testis in each of 9 stallions on day 0. Slight to moderate hemorrhage from the tunica albuginea was observed in 8 stallions, but bleeding from the parenchyma was detected in only 2 stallions. Stallions were castrated 27 days later. Normal development of granulation tissue was evident at the biopsy site, but hematomas were not observed. In situ measurement of the widths of the right and left testes, total scrotal width, and evaluation of testicular echogenicity during ultrasonography were varia...
Godovac-Zimmermann J, Shaw D, Conti A, McKenzie H.The presence of two new alpha-lactalbumins has been demonstrated in the colostrum of a single mare (Equus caballus, Persian Arab). They have been designated equine alpha-lactalbumin B and C, and that isolated previously from the milk of Australian horses (English Thoroughbred) as alpha-lactalbumin A. The primary structures of B/C have been determined by automatic Edman degradation of enzymatic cleavage of the oxidized protein. Cyanogen bromide cleavage of S-carbamoyl-methylated protein provided necessary overlapping peptides. Comparison of the sequences of B and C with that of A indicates 3 an...
Gasthuys F, De Moor A, Parmentier D.The effects of calcium chloride administered at low infusion rates on the cardiovascular depression and the blood calcium balance were studied during a constant halothane anaesthesia in dorsally recumbent ventilated ponies. A pronounced cardiopulmonary depression characterized by decreases of all cardiac parameters and lowering of the mean arterial blood pressure was observed after the initial anaesthetic stabilization period of 30 minutes in the ponies. A significant decrease in the total calcium plasma concentration together with a constant ionized and complexed calcium fraction was present ...
Stubley D, Campbell C, Dant C, Blackmore DJ, Pierce A.The concentration of copper and zinc in the blood and sera of over 300 Thoroughbreds in training was determined by atomic absorption between February 1979 and July 1981. The mean (+/- sd) concentration of copper in the serum of stabled Thoroughbreds (79 +/- 16 micrograms/dl) was significantly (P less than 0.0001) lower than that of those at grass (101 +/- 26 micrograms/dl), whereas the mean serum zinc concentration of stabled Thoroughbreds (170 +/- 54 micrograms/dl) was higher than that of those at grass (111 +/- 45 micrograms/dl). No such differences were observed in whole blood. There were m...
Dodman NH, Shuster L, Court MH, Patel J.Nalmefene, an opioid antagonist, caused a decrease in self-mutilative behavior in a 500-kg stallion. Self-mutilative attempts were counted during a control period and on 4 subsequent occasions after the IM administration of 100 mg, 200 mg, 400 mg, or 800 mg of nalmefene. The frequency of self-mutilation decreased with increasing doses of nalmefene and was virtually abolished with the 800-mg dose.
Hawkins JF, Tulleners EP, Evans LH, Orsini JA.Between 1979 and 1992, the alar folds were resected bilaterally in 22 horses and unilaterally in 2 horses. Abnormal respiratory tract noise and exercise intolerance were the primary complaints prior to surgery. Significantly (P = 0.01) more Standardbreds underwent resection of the alar folds, compared with the number of Standardbreds in the hospital population during the same period. The alar folds palpated abnormally thick in 13 horses and normal in 11 horses. Temporary dilatation of the nares with mattress sutures or clips lessened the respiratory tract noise and improved exercise tolerance ...