"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Nadeau JA, Andrews FM, Patton CS, Argenzio RA, Mathew AG, Saxton AM.To identify the pathogenesis of gastric ulcers by comparing injury to the nonglandular gastric mucosa of horses caused by hydrochloric acid (HCl) or volatile fatty acids (VFAs). Methods: Gastric tissues from 30 horses. Methods: Nonglandular gastric mucosa was studied by use of Ussing chambers. Short-circuit current (Isc) and potential difference were measured and electrical resistance calculated for tissues after addition of HCl and VFAs to normal Ringer's solution (NRS). Tissues were examined histologically. Results: Mucosa exposed to HCl in NRS (pH, 1.5) had a significant decrease in Isc, co...
López-Sanromán FJ, Cruz JM, Santos M, Mazzini RA, Tabanera A, Tendillo FJ.To evaluate the local analgesic effect of ketamine in a palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses. Methods: 36 mature healthy Andalusian horses. Methods: Horses were randomly assigned to 4 groups of 9 horses each and received an abaxial sesamoid block in a randomly chosen forelimb with 1 of the following: saline (0.9% NaCl) solution, 1% ketamine solution, 2% ketamine solution, or 3% ketamine solution. To determine analgesia, the radiant heat lamp-hoof withdrawal model was used as a noxious thermal stimulus. Before each nerve block, basel...
Nadeau JA, Andrews FM, Patton CS, Argenzio RA, Mathew AG, Saxton AM.To identify in vitro effects of hydrochloric acid, valeric acid, and other volatile fatty acids (VFAs) on the pathogenesis of ulcers in the nonglandular portion of the equine stomach. Methods: Gastric tissues from 13 adult horses. Methods: Nonglandular gastric mucosa was studied by use of Ussing chambers. Short-circuit current (Isc) and potential difference were measured and electrical resistance and conductance calculated after tissues were bathed in normal Ringer's solution (NRS) or NRS and hydrochloric, valeric, acetic, propionic, and butyric acids. Treated tissues were examined histologica...
Bueno AC, Galuppo LD, Taylor KT, Jensen DG, Stover SM.To compare the mechanical shear strengths and stiffnesses obtained from in vitro testing of a simulated complete third carpal bone (C3) frontal plane radial facet slab fracture (osteotomy) stabilized with either a 4/5 Acutrak (AT) compression screw or a 4.5-mm AO cortical bone (AO) screw inserted in lag fashion. Drilling, tapping, and screw insertion torques, forces, and times also were compared between AT and AO implants. Methods: In vitro biomechanical assessment of site preparation, screw insertion, and shear failure test variables of bone screw stabilized simulated C3 slab fracture in pair...
Elce YA, Ross MW, Davidson EJ, Tulleners EP.To describe the surgical technique, complications, and outcome of thyroidectomy in 6 horses. Methods: Retrospective study. Methods: Six horses, 10 to 22 years of age, with unilateral, rapidly enlarging thyroid masses. Methods: Medical records between 1985 and 2000 were reviewed for horses that had unilateral thyroidectomy. Retrieved data included signalment, physical, clinical, and ultrasonographic examination findings, surgical technique, complications, and outcome. A minimum of 6 months follow-up was obtained. Results: Six horses were identified. Three horses had tracheal compression and 2 o...
Szeredi L, Tenk M, Schiller I, Révész T.In six healthy mares and 24 mares showing reproductive disorders swab samples were taken from the fossa clitoridis to isolate Taylorella equigenitalis, and from the uterus to isolate mycoplasmas, ureaplasmas and other aerobic bacteria. Swab samples were also taken from the uterus for Chlamydia antigen ELISA and Chlamydia PCR studies. The uterus of 27 mares was examined cytologically, and biopsy samples were taken from the endometrium for histological examinations and for immunohistochemical examinations aimed at the detection of chlamydiae. T. equigenitalis, mycoplasmas, ureaplasmas and chlamy...
Gutierrez CV, Riddle WT, Bramlage LR.To determine whether serum thyroxine (T4) concentration was associated with pregnancy rates 15 to 16 days after ovulation in mares and to determine whether thyroid hormone supplementation would enhance fertility in mares. Methods: Cohort study. Methods: 329 clinically normal broodmares. Methods: Mares were examined 15 to 16 days after ovulation to determine whether they were pregnant; blood samples for determination of serum T4 concentration were collected at the same time. Sixty mares were receiving thyroid hormone supplementation prior to the study because of low serum T4 concentration (< 16...
Giguère S, Gaskin JM, Miller C, Bowman JL.To determine efficacy of a commercially available hyperimmune plasma product for prevention of naturally acquired pneumonia caused by Rhodococcus equi in foals. Methods: Randomized clinical trial. Methods: 165 foals. Methods: Foals were randomly assigned to 1 of 2 groups (hyperimmune plasma or nontreated controls). Foals with failure of passive transfer (FPT) of immunity were treated with hyperimmune plasma and evaluated as a third group. Foals that received plasma were given 950 ml between 1 and 10 days of age and between 30 and 50 days of age. A tracheobronchial aspirate was obtained from fo...
Nedjari M.Investigations to occurrence of Sarcocystiosis of domestic animals in Algeria were carried out by different methods--Immunofluorescence (IFAT), macroscopic and microscopic examinations of muscle, coproscopia. Positive results could be found in intermediate hosts--362 of 537 cattle, 188 of 292 sheep, 13 of 57 horses and in the final hosts dogs and cats. Muscle-probes from cattle contained S. cruzi (58.7 respectively 61.0%), S. hirsuta (48.9 respectively 35.0%), from sheep S. tenella (61.0 respectively 59.6%, S. arieticanis (38.8 respectively 40.3%), from horses S. bertrami (24.5%). IFAT-data of...
Barnewitz D, Evers A, Zimmermann J, Wilke I, Kaps C, Sittinger M.Degenerative alterations in fetlock joints of the forelimb are common diagnoses for horses. The hyaline cartilage has a low capacity to regenerate and the treatment by veterinarians is often insufficient. As a final result, horses with articular cartilage defects are often not able to take part in competitions anymore. To establish an autologous cartilage repair method, we set artificial lesions (8 mm in diameter) into the fetlock joints of the forelimb of three horses. These defects were closed with autologous chondrocyte implants, which were fixed with titan-suture-anchors. After 3, 12 and 2...
Schneider RK, Tucker RL, Habegger SR, Brown J, Leathers CW.To determine clinical signs, diagnostic findings, and outcome for horses with desmitis of the straight sesamoidean ligament (SSL) near its insertion on the middle phalanx. Methods: Retrospective study. Methods: 9 horses. Methods: Medical records were reviewed, and information on signalment, history, clinical signs, diagnostic findings, and treatment was obtained. Follow-up information was obtained through telephone conversations with owners. Results: In all horses, the diagnosis was made by use of high-resolution ultrasonography. Seven horses had moderate lameness on initial examination; lamen...
Shepard EM, Heggem H, Juda GA, Dooley DM.Potential inhibitory effects of the clinically utilized monoamine oxidase inhibitor tranylcypromine (TCP) on mammalian, plant, bacterial, and fungal copper-containing amine oxidases have been examined. The following enzymes have been investigated: human kidney diamine oxidase (HKAO), bovine plasma amine oxidase (BPAO), equine plasma amine oxidase (EPAO), pea seedling amine oxidase (PSAO), Arthrobacter globiformis amine oxidase (AGAO), and Pichia pastoris lysyl oxidase (PPLO). Only BPAO, EPAO, and AGAO were found to lose significant levels of activity when incubated with varying amounts of TCP....
Clark-Price SC, Rush BR, Gaughan EM, Cox JH.A 2-year-old female Quarter Horse was evaluated for hind limb lameness, fever (40 degrees C [104 degrees F]), and lethargy of 2 weeks' duration. Hypoproteinemia characterized by hypoalbuminemia and hyperfibrinogenemia was detected. Abdominal ultrasonography revealed thickening of the right dorsal colon wall. Treatment was instituted for putative right dorsal coliis. Lameness evaluation localized signs of pain to the lumbar vertebrae or pelvis. Radiography performed with the horse standing and nuclear scintigraphy revealed no abnormalities. Ventrodorsal pelvic radiography revealed a focal area ...
Pusterla N, Watson JL, Wilson WD, Affolter VK, Spier SJ.To describe clinical manifestations of cutaneous and ocular habronemiasis in horses and evaluate outcome of treatment. Methods: Retrospective study. Methods: 63 horses. Methods: The diagnosis was made on the basis of history, clinical signs, and identification of calcified concretions (sulfur granules) in lesions. Histologic examination of biopsy specimens was used to confirm the diagnosis. Case horses were compared with a control population of 12,720 horses examined during the same period. Results: Arabians, gray horses, and horses with diluted coat colors were overrepresented; Thoroughbreds ...
Dionne RM, Vrins A, Doucet MY, Paré J.This study was performed to estimate the prevalence of gastric ulcers in Standardbred racehorses, to describe the lesion score and location, and to identify potential risk factors. Two hundred seventy-five (275) Standardbred horses from 5 training centers and 2 racetracks in Quebec, Canada, were studied. Historical data for the 2 months before examination were recorded for each horse, and the presence of gastric ulcers was determined by gastroscopy. A previously reported scoring system that used grades 0-3 for gastric lesions was used. Overall, 121 horses (44.0%; 95% CI, 38.1-50.1%) had gastri...
Fielding CL, Magdesian KG, Elliott DA, Craigmill AL, Wilson WD, Carlson GP.The purpose of this study was to describe the pharmacokinetics of bromide in horses and to evaluate the corrected bromide space as an indicator of extracellular fluid volume (ECFV) in horses after the administration of a single dose of bromide by intravenous infusion. Sodium bromide (30 mg/kg of body weight, IV) was administered to 6 clinically healthy mares over a period of 3 minutes. Blood samples were collected before infusion and at intervals between 0.5 hours and 53 days after infusion. Mean elimination half-life (harmonic mean) was 126 hours (5.2 days), clearance was 1.4 +/- 0.09 mL/(kg ...
Wijnberg ID, Franssen H, Jansen GH, Back W, van der Kolk JH.Electromyographic needle examination (EMG), including the semiautomatic quantitative analysis of motor unit action potential (MUAP), is an important diagnostic tool for myopathy in humans. The diagnostic possibilities of this technique have not been fully explored in horses; however, recent studies have shown that MUAP analysis can be performed in conscious horses. To determine the diagnostic possibilities of EMG in horses, we compared the EMG results of the subclavian muscle, the triceps, and the lateral vastus muscle in 6 equine patients thought to have myogenic disorders with those in 7 nor...
Carroll J, Murphy CJ, Neitz M, Hoeve JN, Neitz J.Horses, like other ungulates, are active in the day, at dusk, dawn, and night; and, they have eyes designed to have both high sensitivity for vision in dim light and good visual acuity under higher light levels (Walls, 1942). Typically, daytime activity is associated with the presence of multiple cone classes and color-vision capacity (Jacobs, 1993). Previous studies in other ungulates, such as pigs, goats, cows, sheep and deer, have shown that they have two spectrally different cone types, and hence, at least the photopigment basis for dichromatic color vision (Neitz & Jacobs, 1989; Jacob...
Bailey SR, Baillon ML, Rycroft AN, Harris PA, Elliott J.Acute laminitis has been associated with the overgrowth of gram-positive bacteria within the equine hindgut, causing the release of factor(s) leading to ischemia-reperfusion of the digits. The products of fermentation which trigger acute laminitis are, as yet, unknown; however, vasoactive amines are possible candidates. The objectives of this study were to use an in vitro model of carbohydrate overload to study the change in populations of cecal streptococci and lactobacilli and to establish whether certain species of these bacteria were capable of producing vasoactive amines from amino acids....
Wagner HM, Balasuriya UB, James MacLachlan N.In an effort to further characterize the humoral immune response of horses to equine arteritis virus (EAV), direct and competitive enzyme-linked immunosorbent assays (c-ELISAs) were developed using monoclonal and polyclonal anti-sera to structural (G(L), N and M) and non-structural (nsp1) viral proteins. A nsp1-specific monoclonal antibody was produced to facilitate development of a c-ELISA to this protein. Data obtained using the various c-ELISAs confirm that the M protein is a major target of the antibody response of horses to EAV. However, none of the c-ELISAs that were developed were as se...
Golland LC, Evans DL, McGowan CM, Hodgson DR, Rose RJ.Red blood cell hypervolaemia has been used for diagnosis of overtraining in racehorses, and has been suggested as a mechanism of this cause of loss of racing performance. The effects of overload training (OLT) on the plasma, blood and red cell volumes were investigated in a prospective study in 12 Standardbred horses. Measurements of blood volumes were made after eight and 32 weeks of an exercise training study. Horses were randomly allocated to OLT and control groups (n=6) after 16 weeks of training. Training duration and intensity were increased more rapidly for the OLT group from week 16, u...
Törneke K, Ingvast-Larsson C, Pettersson K, Bergvall K, Hedeland M, Bondesson U, Broström H.Clemastine is an H1 antagonist used in certain allergic disorders in humans and tentatively also in horses, although the pharmacology of the drug in this species has not yet been investigated. In the present study we determined basic pharmacokinetic parameters and compared the effect of the drug measured as inhibition of histamine-induced cutaneous wheal formation in six horses. The most prominent feature of drug disposition after intravenous dose of 50 microg/kg bw was a very rapid initial decline in plasma concentration, followed by a terminal phase with a half-life of 5.4 h. The volume of d...
Peters M, Graf G, Pohlenz J.A 14-year-old standardbred mare with clinically suspected acute bronchitis was killed because of rapidly progressing central nervous disturbances. Necropsy revealed systemic granulomatous inflammation and vasculitis involving the lungs, thoracic lymph nodes, ribs, and liver. In the cerebrum there was a severe subacute bilateral encephalitis and malacia predominately affecting the white matter, and vasculitis with perivascular infiltration of lymphocytes, macrophages, and giant cells. A causative infectious agent could not be detected by Ziehl-Neelsen, Grocott, or Giemsa stains, by periodic aci...
Johnson CB, Bloomfield M, Taylor PM.The electroencephalographic (EEG) effects of a rapid infusion of midazolam and sarmazenil following a bolus of midazolam were investigated in eight Welsh mountain ponies anaesthetized with 0.8% halothane in oxygen. The peak plasma concentration of midazolam was 2.13 +/- 0.34 ng/mL (mean +/- SD) occurring 5 min after the start of the infusion. Sarmazenil concentrations were not measured. The 95% spectral edge frequency of the EEG decreased by a maximum of 39.8 +/- 15.8%, 10 min after the start of the midazolam infusion. No changes were seen in median frequency of the EEG or the second different...
Clough H, Roshier M, England G, Burford J, Freeman S.This cross-sectional study aimed to investigate factors affecting horse owners' purchase and euthanasia decisions that had been identified in a qualitative study. An online survey on horse owners' purchase and euthanasia decisions and experiences was distributed using snowball sampling. Inclusion criteria were previous experience of purchase or euthanasia decisions. Descriptive data analyses (mean, median, mode and frequency percentages) were performed. There were 451 participants from the UK and Ireland, 97% were female with a median age of 45 years. Participants most frequently did not seek ...
Bochkova NG, Koreshkova GV, Pogodina VV.A total of 5227 serum specimens from humans, horses and swine collected in the seasons of 1968--1976 in 15 administrative areas of the Primorskiy Kray were examined with antigens of a number of mosquito-borne arboviruses: Japanese encephalitis (JE), West Nile (WN), Getah, and Sindbis. Both independent and combined circulation of these viruses in the region was established. Sindbis virus was found to be circulating separately most frequently, West Nile virus the least frequently. According to the results of the serological analysis, the conditions for combined circulation are most closely relat...
Walker AM, Wilson AM, Pfau T.When assessing lameness in horses, left to right ratios of kinematic parameters are often used to quantify movement symmetry. Different methods of symmetry related measures have been proposed and inertial sensor data was used to evaluate the application of 3 methods of symmetry calculation during straight and circular trotting. Objective: To compare 3 sensor based methods of symmetry index calculation to assess; tuber coxae vs. sacrum motion, the effects of circular trotting and effect of using whole trials in place of individual stride calculations. Methods: Inertial sensors were attached to ...
Hudson LC, Weinstock D, Jordan T, Bold-Fletcher NO.Twelve naive and nine test-vaccinated horses which developed clinical signs of rabies as a result of the required protocol of a vaccine trial were prospectively observed. Nineteen of the 21 cases were confirmed positive for rabies infection of the brain by fluorescent antibody test. The two horses with negative results had ganglioneuritis of the trigeminal ganglion or lymphocytic perivascular cuffing in the brain stem in addition to clinical signs. Average incubation period was 12.3 days and average morbidity was 5.5 days. Naive animals had significantly shorter incubation and morbidity period...
Bailey DN.The relative binding of acetaminophen, lidocaine, phenobarbital, procainamide, quinidine, and theophylline to sera of seven mammalian species was studied. Pooled commercial sera from cow, goat, horse, human, pig, rabbit, and sheep were supplemented with 5 and 10 mM concentrations of each drug. For each serum, each drug, and each drug concentration, equilibrium dialysis was performed in duplicate against phosphate buffer (pH 7.4, 0.1 M, 4 degrees C). Percent drug bound to serum was calculated. Phenobarbital demonstrated more than 20% binding to goat, horse, human, and sheep serum at both 5 and ...
Tizzoni R, Tizzoni M.The present case illustrates how a tooth, which had a highly questionable prognosis, was preserved by carrying out a periodontal regeneration surgery. Background: Treatment of periodontitis involves a careful consideration of all the factors that may allow the achievement of a favorable outcome; among those, the skillful use of guided tissue regeneration (GTR) membranes is of paramount importance. Methods: A 39-year-old patient presented with a mobile central upper incisor due to severe periodontitis and was treated according to GTR principles using a collagen membrane. A collagen-preserving b...
Clayton HM, White AD, Kaiser LJ, Nauwelaerts S, Lavagnino M, Stubbs NC.A lightweight bracelet that provides tactile stimulation to the horse's pastern and coronet induces a higher flight arc of the hoof. This study addresses the pattern of habituation to these devices. Objective: To evaluate short-term habituation to tactile stimulation of the pastern and coronet in trotting horses. Methods: Tactile stimulation was provided by a lightweight (55 g) device consisting of a strap with seven chains that was attached loosely around the pastern. Reflective markers were fixed to the dorsal hoof wall, the forehead and over the tenth thoracic vertebra of eight sound horses...
Volkmann DH, Williams JH, Henton JH, Donahue JM, Williams NM.Since the late 1980s a distinct form of focally-extensive mucoid to mucopurulent uterine body chronic placentitis,caused by nocardioform organisms, hasbeen recognised in horses in the USA state of Kentucky and possibly in other areas. This disease has led to increasing numbers of foal losses from late abortions, still-births, prematurity, or early neonatal deaths. The foals are usually not infected, but may be small or emaciated. Modes of infection and transmission are as yet unknown. Nocardia spp. and related nocardioform bacteria as causes of equine infertility, endometritis and foal death a...
Silva ILS, Junqueira GSB, Oliveira CAA, Costa RB, DE Camargo GMF.Grullo is a dun dilution on a black coat that is common in the Campolina horse: an autochthonous Brazilian breed. The aims of this case study were to evaluate inconsistencies in grullo coat color registration and to explain their possible causes. A total of 3,270 grullo Campolina horses were evaluated. To confirm the genetic possibility of having grullo animals, the coat color genotypes of parents were inferred by phenotype and compared with those of progeny. A total of 242 horses that were registered as grullos could not have this coat based on their parents' information. Possible explanation...
Clayton HM, Duncan JL.Six worm-free pony foals, two to four months old, were infected with parascaris equorum eggs using three different dosage regimes and killed at either 40 or 95-100 days after infection. Coughing and a circulating eosinophilia were features of large infections from which only a small number of worms developed to maturity. In small infections a high percentage of the parasites matured in the small intestine and this was associated with unthriftiness. Pre-patent periods of 80 and 83 days were recorded.
Durham AE, Phillips TJ, Walmsley JP, Newton JR.Several clinical variables were compared in two groups of 15 horses recovering from resection and anastomosis of a strangulated small intestine; 15 were treated with parenteral nutrition and 15 were starved routinely. There was some evidence that parenteral nutrition had a short-lived adverse effect on both the catheter sites and gastric emptying, but there were no marked adverse clinical effects and no evidence of any improvement in the horses' condition.
Skipper L, Pusterla N.The purpose of this study was to establish if peak serum amyloid A (SAA) concentrations can be used to determine an appropriate immune response to a vaccine containing West Nile Virus (WNV) antigen. A pilot study with 20 clinically healthy horses was performed to identify peak SAA concentration postvaccination with a commercial multivalent WNV vaccine. Blood was collected for SAA at 0, 24, 48, 72, 96, 168 hours postvaccination. Serum for WNV serum neutralization antibody testing was obtained immediately prior to and 30 days postvaccination. An additional 40 horses underwent the study protocol,...
Nyman G, Björk M, Funkquist P.To investigate the gas exchange response during exercise in horses with mild bronchiolitis (MB), we studied 7 Standardbred trotters. In order to determine pulmonary gas exchange and red cell volume in relation to bodyweight (CV/BW), submaximal graded exercise tests were performed. VO2 was monitored from an open bias flow system without valves. Heart rate, respiratory rate and mean pulmonary and systemic artery pressures were measured. Cardiac output and alveolar ventilation were calculated. Arterial and mixed venous blood were drawn for blood gas analysis and pH measurements. Pulmonary gas exc...
Mienaltowski MJ, Belt A, Henderson JD, Boyd TN, Marter N, Maga EA, DePeters EJ.Prophylactic supplementation of psyllium husk is recommended to enhance passage of ingested sand from the gastrointestinal tracts of horses. We hypothesized that psyllium supplementation would increase fecal sand passage and favorably alter bacterial populations in the hindgut. Six yearlings and six mature mares were fed a psyllium supplement in the diet daily for seven days. Voluntarily-voided feces were collected over the course of 29 days, prior, during, and after treatment. Feces were analyzed for acid detergent fiber (ADF) and acid detergent insoluble ash analyses. Microbial DNA was also...
Liebermann H.Sera collected from 124 horses were checked by means of the serum neutralisation test against equine Bern virus. Torovirusspecific antibodies were recordable from 35 percent of all horses tested. These results are likely to suggest that toroviruses are widespread in the GDR and occur not only in horses but in other domestic animals and in man, as well.
Weiss DJ, Evanson OA.To determine the potential usefulness of tests for detection of platelet activation and platelet-leukocyte aggregates in horses. Methods: Blood from 3 healthy Thoroughbreds. Methods: Microscopic and flow cytometric assays were used to evaluate spontaneous platelet aggregation, platelet activation, and platelet-leukocyte aggregates. Platelet activation was detected by evaluation of binding of anti-human fibrinogen to unactivated and ADP-, thrombin-, thrombin agonist receptor peptide-, and platelet activating factor-activated platelets. Platelet-leukocyte aggregates were evaluated microscopicall...
Verschooten F, Verbeeck J.This paper describes the application of a measuring device 'Flextest' to control the effect of traction force and traction time during flexion tests of the distal limb joints of the forelimbs. The optimal force for a flexion test is 100 N, over 1 min. A higher force (150 N) was not harmful. A slightly positive flexion response (100 N/1 min) in a horse with no other clinical signs or radiographic abnormalities is not of clinical significance. Individual left and right flexion and extension angles are almost identical and do not depend on age. Stabled horses which have been rested or horses rest...
Maulave J, Mascaró Triedo C, Portier K.To assess the reliability of a French version of the Horse Grimace Scale (HGSfv). Methods: Prospective, randomized, clinical study. Methods: The operated (OP) group included 13 horses undergoing elective surgery. The positive (PC) and negative control (NC) groups included seven colicking horses and eight exercising sport horses, respectively. Methods: Photographs were extracted from videos of the horses' heads. Videos were taken before and immediately after surgery in OP, on arrival of the horse in PC, and at rest in their stalls in NC. Pictures were evaluated by three anaesthetists [Diplomate...
Murray MJ, Cavey DM, Feldman BF, Trostle SS, White NA.Sympathetic denervation in a 20-year-old, gray, Thoroughbred-Percheron gelding was manifested by cutaneous hyperthermia and sweating over the right side of the body, demarcated by a line from the withers to the elbow and extending cranially. There was cutaneous hyperthermia over the right side of the head, but other signs of Horner's syndrome (sweating, ptosis, miosis, enophthalmos) were not present. The pattern of cutaneous hyperthermia and sweating was consistent with sympathetic denervation localized to the cervicothoracic ganglion, and thoracic radiographs revealed increased density in the...
Raidal SL, Taplin RH, Bailey GD, Love DN.To evaluate the administration of procaine penicillin prior to or during confinement with head elevation as a means of reducing the associated accumulation of inflammatory lower respiratory tract secretions and increased numbers of bacteria within the lower respiratory tract of confined horses. Methods: Two experiments were conducted to evaluate the efficacy of different dose rates and dosing frequencies. In experiment A a single low dose (15,000 IU/kg) of procaine penicillin was administered to four horses immediately prior to confinement with head elevation for 48 hours. The systemic leucocy...
Watson ED, Thomson SR.Aromatase P-450 (P-450arom) is a crucial regulatory enzyme that is necessary for conversion of androgens to oestrogens. Corpora lutea and follicles were obtained from the ovaries of cyclic mares and from mares at day 20 and days 40-70 of pregnancy. The presence of P-450arom within specific cell types was investigated by immunostaining to determine potential sites of oestrogen synthesis. Immunoreactivity for P-450arom was confined to the granulosa layer of non-atretic follicles > 5 mm in diameter and to corpora lutea at all stages of the oestrous cycle and during pregnancy. These findings co...
Coffman EA, Abd-Eldaim M, Craig LE.A pregnant 18-year-old Quarterhorse mare presented with fever, anorexia, tachycardia, tachypnea, and gastrointestinal hypermotility at day 68 of gestation. Potomac horse fever was diagnosed based on polymerase chain reaction (PCR) analysis of whole blood and a high antibody titer to Neorickettsia risticii. The mare made a rapid clinical recovery following antibiotic therapy, but aborted 98 days later. Necropsy on the aborted fetus revealed lymphohistiocytic colitis, lymphadenitis, myocarditis, and hepatitis. The placenta was grossly and histologically normal. Formalin-fixed lymph node, thymus,...
Recknagel S, Nicke M, Schusser GF.To evaluate the diagnostic value of peritoneal fluid (PF) cytology for clinical diagnosis of abdominal neoplasia in horses. Methods: Ten horses with histopathologically confirmed abdominal neoplasia, in which a PF analysis was performed, were included in this retrospective study. PF was analyzed for total protein concentration and a nucleated cell count was performed. Using cytological criteria of malignancy, the PF samples were evaluated regarding their probability of malignancy. Results: Cytologic classification of cells according to criteria of malignancy allowed a positive cytologic diagno...
