"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.
Crawford C, Sepulveda MF, Elliott J, Harris PA, Bailey SR.Pasture-induced laminitis in the horse is associated with the overconsumption of fermentable carbohydrate, in the form of simple sugars, fructans, or starch. The fermentation of carbohydrate in the cecum and large intestine results in the production of lactic acid and other toxins or "laminitis trigger factors." Vasoactive amines have been suggested as possible initiating factors. The aim of this study was to feed a commercially available form of fructan carbohydrate (inulin, 3 g/kg of BW per day) to normal ponies and to ponies predisposed to laminitis, to mimic a change from a basal hay diet ...
Kulikova EE, Isaeva AS, Rotkina AS, Manykin AA, Letarov AV.The complex cellulolytic microbial community of the horse intestines is a convenient model for studying the ecology of bacteriophages in natural habitats. Unlike the rumen of the ruminants, this community of the equine large intestine is not subjected to digestion. The inner conditions of the horse gut are much more stable in comparison to other mammals, due to the fact that the horse diet remains almost unchanged and the intervals between food consumption and defecation are much shorter than the whole digestive cycle. The results of preliminary analysis of the structure and dynamics of the vi...
Ceroni D, De Rosa V, De Coulon G, Kaelin A.We report 4 cases of nutcracker fractures of the cuboid resulting from equestrian sport in pediatric population. These lesions are often consistent with a trauma in forced abduction of the forefoot. The particular mechanism of the cuboid fracture due to horseback riding in children is discussed. The methods used to radiographically evaluate the compression fracture of the cuboid and its associated injuries are presented. Left untreated, these fractures can lead to severe alterations in foot mechanics and function, such as to severe pain. In addition, the surgical treatment to correct the nutcr...
Weng Q, Tanaka Y, Taniyama H, Tsunoda N, Nambo Y, Watanabe G, Taya K.To elucidate the relationship between steroidogenic hormones and developing adrenal glands, we investigated the immunolocalization of steroidogenic enzymes in equine fetal adrenal glands during mid-late gestation. Fetal adrenal glands were obtained from three horses at 217, 225 and 235 days of gestation. Steroidogenic enzymes were immunolocalized using polyclonal antisera raised against bovine adrenal cholesterol side-chain cleavage cytochrome P450 (P450scc), human placental 3beta-hydroxysteroid dehydrogenase (3betaHSD), porcine testicular 17alpha-hydroxylase cytochrome P450 (P450c17) and huma...
Njiru ZK, Constantine CC.To investigate the population genetic structure of Trypanosoma evansi from domesticated animals, we have analysed 112 stocks from camels, buffaloes, cattle and horses using the tandemly repeated coding sequence (MORF2) and minisatellite markers 292 and cysteine-rich acidic integral membrane protein (CRAM). We recorded a total of six alleles at the MORF2 locus, seven at 292 and 12 at the CRAM loci. Nei's genetic distance showed reduced allelic diversity between buffaloes and cattle stocks (1.2) as compared to the diversity between camels and buffaloes (3.75) and camels and cattle stock (1.69). ...
Fraga M, Perelmuter K, Delucchi L, Cidade E, Zunino P.Lactic acid bacteria (LAB) are important members of the human vaginal microbiota and their presence is considered beneficial. However, little is known about native vaginal bacteria in other animal species such as the horse. The aim of this work was to quantify the vaginal lactic acid bacteria and lactobacilli of mares and to establish if selected equine vaginal lactic acid bacteria, particularly Lactobacillus and Enterococcus spp. strains, could exhibit potential as probiotics. The vaginal lactic acid bacteria and lactobacilli of 26 mares were quantified by plate counts. Five strains (three La...
Riddle WT, LeBlanc MM, Stromberg AJ.Endometrial cytology and culture specimens (n=2123) were collected concurrently with a guarded uterine culture instrument from 970 mares (738 barren, 1230 foaling and 155 maiden mares) during three breeding seasons (2001-2004). Results were compared to the 28-d pregnancy rate for the cycle from which the samples were taken. Cytological smears were evaluated for inflammation at x100 and graded as: not inflammatory (0-2 neutrophils/field), moderate inflammation (2-5 neutrophils/field), severe inflammation (>5 neutrophils/field), or hypocellular (scant epithelial cells and no neutrophils). Ute...
Lansade L, Bouissou MF, Boivin X.The purpose of this study was to investigate the development and the stability across situations and over time of three temperament traits in young foals: propensity to react to humans, propensity to react to novelty, and propensity to react to suddenness. In a comparative study, we examined the reactions of animals in three independent groups (N = 27) tested at 3, 12, and 24 weeks of age, respectively. We observed that human avoidance and novel object approach behaviors are quasi inexistent in the group tested at 3 weeks, but are more and more present in the groups tested at subsequent ages. ...
Henry S, Briefer S, Richard-Yris MA, Hausberger M.A recent study has shown that gently handling dams in front of their few days old foals may strongly influence the development of human-foal relationships. In the present study, we test whether 6-month-old foals remain sensitive to their dams' influence. The study was performed on 16 foal-mare dyads, with half of the mares receiving positive contacts from the experimenter in presence of their 6-month-old foals (n = 8) whereas the other mares were not handled (n = 8). All foals were tested 15 and 30-35 days later under various conditions (reaction to a motionless human, approach test, saddle-pa...
Olsén L, Bondesson U, Broström H, Tjälve H, Ingvast-Larsson C.The pharmacokinetics of the histamine H(1)-antagonist cetirizine and its effect on histamine-induced cutaneous wheal formation were studied in six healthy horses following repeated oral administration. After three consecutive administrations of cetirizine (0.2 mg/kg body weight, bw) every 12h, the trough plasma concentration of cetirizine was 16+/-4 ng/mL (mean+/-SD) and the wheal formation was inhibited by 45+/-23%. After four additional administrations of cetirizine (0.4 mg/kg bw) every 12 h, the trough plasma concentration was 48+/-15 ng/mL and the wheal formation was inhibited by 68+/-11%....
Gatherer ME, Faulkner J, Voûte LC.The aim of this study was to compare the radiation doses received by the personnel drawing up and injecting the radiopharmaceutical and operating the nuclear scintigraphy equipment, and those restraining nine horses while they were being scanned during scintigraphic investigations of lameness. Sensitive electronic dosimeters were worn by the personnel and the doses they received during the administration of the radiopharmaceutical and during the period of image acquisition were recorded at intervals. On average, 90 per cent of the total doses were received during the period of image acquisitio...
Aleman M, Magdesian KG, Peterson TS, Galey FD.A 4-month-old American Paint filly was evaluated because of sudden onset of ataxia that progressed to recumbency. Five additional horses from the same and neighboring premises developed signs of poor performance, generalized weakness, ataxia, and recumbency; 2 of those horses were also evaluated. A new batch of a commercial feed supplement had been introduced to the horses' diet on each farm within the preceding 3 days. Results: Other than recumbency, findings of physical and neurologic examinations of the foal were unremarkable. The other 2 horses had generalized weakness and mild ataxia, and...
Ramery E, Closset R, Bureau F, Art T, Lekeux P.Environmental causes of heaves are well described, but the molecular mechanisms of the disease remain unclear. Previous studies have highlighted the implications of variations in gene expression, most using reverse transcription polymerase chain reaction (RT-PCR). This well-known technique limits the number of genes that can be studied in a single assay. Microarray appears to be a valuable tool to by-pass this limitation, but so far there has been no equine-specific microarray available on the market. The present study was performed to determine whether a human microarray could be used to stud...
Ringer SK, Kalchofner K, Boller J, Fürst A, Bettschart-Wolfensberger R.To compare the effects of two balanced anaesthetic protocols on end-tidal isoflurane (Fe'ISO), cardiopulmonary performance and quality of recovery in horses. Methods: Prospective blinded randomized clinical study. Methods: Sixty-nine client-owned horses, American Society of Anesthesiologists category I and II, undergoing elective surgery. Methods: The horses were premedicated with acepromazine (0.03 mg kg(-1)) IM 30-60 minutes before induction of anaesthesia and were randomly assigned to one of two treatments: in group L (37 horses) xylazine (1 mg kg(-1)) and in group M (31 horses) medetomidin...
Bugno M, Słota E, Kościelny M.Five hundred young horses of the following breeds: Thoroughbred, Silesian, Malopolska, Wielkopolska, Polish Konik, Hutsul, Shetland Pony, Half-bred Anglo-Arabian, Noble Half-bred, Fjord and crosses were cytogenetically investigated. Chromosome preparations obtained after lymphocyte culture were analysed using conventional Giemsa staining and CBG-banding methods. In the case of abnormalities GTG-banding as well as FISH technique were applied. In ten mares different karyotypic abnormalities were diagnosed. One mare showed chromosome chimerism (64,XX/64,XY), eight had sex chromosomal aneuploidy (...
Rivera Del Alamo MM, Reilas T, Kindahl H, Katila T.Intrauterine glass balls are used to prevent oestrous signs in sports mares, but the mechanism of action is unknown. It has been suggested that the glass ball can mimic an embryo or act via an induced chronic uterine inflammation and absent or continuous low-grade prostaglandin (PG) release. The purpose of this study was to induce prolonged luteal function in mares using a small intrauterine device (IUD) and to study the mechanisms behind prolonged IUD-induced luteal function. A uterine swab and a biopsy specimen were obtained in early oestrus. A water-filled plastic ball, diameter 20mm and we...
Geutjens CA, Clayton HM, Kaiser LJ.The objective was to use an electronic pressure mat to measure and compare forces and pressures of the saddle on a horse's back when riders mounted from the ground and with the aid of a mounting platform. Ten riders mounted a horse three times each from the ground and from a 35 cm high mounting platform in random order. Total force (summation of forces over all 256 sensors) was measured and compared at specific points on the force-time curve. Total force was usually highest as the rider's right leg was swinging upwards and was correlated with rider mass. When normalized to rider mass, total fo...
Sasaki N, Murata A, Lee I, Yamada H.Horses often suffer reduced intestinal motility after jejunocecostomy. Therefore, accurate evaluation of intestinal motility is important for the prevention, diagnosis and treatment of this condition. The purpose of this study was to evaluate intestinal motility in horses after jejunocecostomy using three different methods, i.e. auscultation, ultrasonography and electrointestinography. Methods: Six healthy thoroughbreds were used in this study. They were subjected to jejunocecostomy. Methods: Bowel sounds in the right paralumbar fossa were assigned a score of 0-3 for intestinal motility evalua...
Eckert RE, Neuder LE, Bell JL, Trujillo JC, Jones SL.The goal of this study was to define the role for p38 mitogen-activated kinase (MAPK) in the signaling mechanism regulating pro-inflammatory cyclooxygenase (COX) gene expression in lipopolysaccharide (LPS)-activated equine leukocytes for the purposes of identifying novel targets for anti-inflammatory therapy in endotoxemic horses. The p38 MAPK has been shown to positively regulate inflammatory gene expression in human leukocytes and can be activated by a variety of stimuli including LPS, TNF-alpha, and IL-1. Activation-associated phosphorylated p38 MAPK has been implicated in the up-regulation...
Rossetti RB, Gaido Cortopassi SR, Intelizano T, de Lima Machado TS, Ferreira da Cruz RS.To compare the quality of induction and recovery, degree of muscle relaxation, clinically apparent potency and cardiopulmonary effects of racemic ketamine or S(+)-ketamine when used for total intravenous anesthesia in horses. Methods: Prospective randomized clinical trial Methods: Sixteen healthy stallions (323 +/- 99 kg), with a mean age of 6.2 years, undergoing castration. Methods: Horses were pre-medicated with romifidine IV, 15 minutes before induction of anesthesia. Each animal was then randomly allocated to receive either diazepam and ketamine (DK) or diazepam and S(+)-ketamine (DKS) at ...
Clark L, Clutton RE, Blissitt KJ, Chase-Topping ME.To investigate the effects of peri-operative morphine on the quality and duration of recovery from halothane anaesthesia in horses. Methods: Prospective randomized study. Methods: Twenty-two client owned horses, ASA category I or II. Methods: Horses undergoing elective surgical procedures were divided into two groups and paired according to procedure, body position during surgery, body mass and breed. Group M+ received morphine by intravenous injection (0.15 mg kg(-1)) before induction of anaesthesia and then by infusion (0.1 mg kg(-1) hour(-1)) during anaesthesia. Group M- received the same a...
Thomasy SM, Moeller BC, Stanley SD.To compare the density and binding characteristics of opioid receptor subtypes in horse, rat, and guinea pig cerebral cortex and cerebellum. Methods: Prospective receptor binding study. Methods: Whole brains were obtained from four neurologically normal adult horses during necropsy. Rat and guinea pig brains were obtained commercially. Methods: The cerebellum and cerebral cortex were dissected from each brain, and tissue homogenates prepared. A radioligand binding technique with the highly selective ligands [(3)H]-DAMGO, [(3)H]-U69593, and [(3)H]-DPDPE was used to identify the mu- (mu), kappa-...
Bezdekova B, Jahn P, Vyskocil M.Gastroduodenal ulceration is a prevalent disease in foals and adult horses. Decreased performance as well as fatal complications relate to this syndrome. The objective of our study was to determine the prevalence of gastric ulceration in a mixed population of horses by postmortem examination and to evaluate a possible association between equine gastric ulcer syndrome (EGUS) and sex or age of the examined horses, to evaluate the localisation of lesions in the proximal part of the gastrointestinal tract and to determine the occurrence of gastric parasites. Postmortem examinations were performed ...
Wittwer C, Löhring K, Drögemüller C, Hamann H, Rosenberger E, Distl O.The aim of this study was to identify quantitative trait loci (QTL) for osteochondrosis (OC) and palmar/plantar osseous fragments (POF) in fetlock joints in a whole-genome scan of 219 South German Coldblood horses. Symptoms of OC and POF were checked by radiography in 117 South German Coldblood horses at a mean age of 17 months. The radiographic examination comprised the fetlock and hock joints of all limbs. The genome scan included 157 polymorphic microsatellite markers. All microsatellite markers were equally spaced over the 31 autosomes and the X chromosome, with an average distance of 17.7...
Barton MH, LeRoy BE.Reference ranges for serum bile acids (SBA) concentration are well established in healthy adult horses. Increased values are indicative of hepatic disease. Objective: SBA concentrations are significantly greater in the neonatal period compared with mature horses, and illness in the neonatal period will further increase SBA. Methods: Ten healthy mature horses, 12 healthy foals, and 31 clinically ill foals. Methods: Prospective cross-sectional study. Blood samples were obtained once from the mature horses, from healthy foals immediately after birth, at 2 days, and at 1, 2, 3, 4, and 6 weeks of a...
Borges AS, Divers TJ, Stokol T, Mohammed OH.Detection of systemic inflammation, which is important for proper diagnosis and prompt treatment, can be challenging. Objective: Measurement of plasma iron concentration is a sensitive method for detecting systemic inflammation in horses compared with measurements of plasma fibrinogen concentration, a traditional marker for inflammation in the horse. Methods: Ninety-seven horses hospitalized with diseases causing systemic inflammation, 22 horses with localized inflammation, and 12 clinically normal horses were included in this study. Methods: A retrospective study was made on hospitalized hors...
Vera L, Van Steenkiste G, Decloedt A, Chiers K, van Loon G.Arterial rupture mainly affects older horses. The reason why older horses are more prone to arterial rupture and which underlying vascular changes predispose older horses to aortic rupture is still unclear. Objective: To investigate the effect of ageing on the equine arterial wall and blood pressure. Methods: Cohort study. Methods: Non-invasive blood pressure measurement using a tail cuff and vascular ultrasound from aorta, common carotid artery and external iliac artery was performed in 50 healthy young (3-7 years) and 50 healthy old Warmblood horses (>18 years). Arterial diameters and c...
Douglas RH, Ginther OJ.In experiment 1, seven groups of pony mares (2 or 3/group) were given either no injections (controls), or 5 (5X) or 10 (10X) daily subcutaneous (SC) injections of 1.25 mg PGF2alpha beginning on days 1, 7 or 13 post-ovulation. Compared to controls (24.5 days), the interovulatory interval was longer (P less than ..05) for day 7, 10X (33.5 days) and day 13, 10X mares (49.0 days) but was not different for the remaining groups. In experiment 2, nine groups of pony mares (4/group) were given either no injections (controls) or 1 (1X) or 10 (10X) daily SC injections of 1.25 mg PGF2alpha beginning on d...
Schauvliege S, van Loon G, De Clercq D, Devisscher L, Deprez P, Gasthuys F.To examine the influence of direct current shock application in anaesthetized horses with atrial fibrillation (AF) and to study the effects of cardioversion to sinus rhythm (SR). Methods: Prospective clinical study. Methods: Eight horses successfully treated for AF (transvenous electrical cardioversion after amiodarone pre-treatment). Methods: Cardioversion catheters and a pacing catheter were placed under sedation [detomidine 10 microg kg(-1) intravenously (IV)]. After additional sedation (5-10 microg kg(-1) detomidine, 0.1 mg kg(-1) methadone IV), anaesthesia was induced with ketamine, 2.2 m...
Lowder MQ, Mueller PO.Equine practitioners should be knowledgeable of dental anatomy and development to enhance their skill of age estimation of horses. The permanent teeth of horses are continually undergoing changes in shape and appearance. These changes may be used to suggest a reasonable age range for a horse.
Cauvin ER, Munroe GA, Boyd JS.This study was undertaken to design a safe technique to examine the carpal flexor tendon sheath (carpal sheath) of horses endoscopically, using an arthroscope. The limbs from 15 horses were used to study the normal anatomy of the carpal sheath and related structures, establish a safe approach and endoscopic technique, and determine the normal endoscopic appearance of the sheath. Major arteries, veins and nerves, present within and around the sheath, left few 'safe' areas to insert the endoscope. Several portals were assessed and a distal lateral approach was found to be safest and to allow ade...
Skarda RT, Muir WW.A new technique for producing continuous caudal epidural analgesia (CEA) and caudal subarachnoid analgesia (CSA) in adult horses (mares) without causing loss of pelvic limb function is described. A modified 17-gauge Huber-point directional needle was used to place a catheter with stylet into either the epidural or subarachnoid space at the lumbosacral intervertebral junction. The catheter was positioned at either the midsacral (S2-3) subarachnoid space or caudal portion of the sacral (S-3 to S-5) epidural space in 7 mares. The position of the catheter was confirmed radiographically. A 2% solut...
Zweygarth E, Lopez-Rebollar LM, Meyer P.Twenty blood samples of zebras (Equus zebra zebra) from the Karoo National Park and the Bontebok National Park in South Africa, all seropositive for Theileria equi, were subjected to in vitro culture to identify carrier animals and to isolate the parasites. Sixteen animals had a detectable parasitaemia in Giemsa-stained blood smears examined before culture initiation, the remaining four animals were identified as T. equi carriers by in vitro culture. Cultures were initiated either in an oxygen-reduced gas mixture or in a 5% CO2-in-air atmosphere. Out of the 20 blood samples, 12 cultures of T. ...
Fenger CK, McKeever KH, Hinchcliff KW, Kohn CW.To determine components of the increase in oxygen consumption (VO2) and evaluate determinants of hemoglobin saturation (SO2) during incremental treadmill exercise in unfit horses. Methods: 7 unfit adult mares. Methods: Horses performed 1 preliminary exercise test (EXT) and 2 experimental EXT. Arterial and mixed venous blood samples and hemodynamic measurements were taken during the last 30 seconds of each step of the GXT to measure PO2, hemoglobin concentration ([Hb]), SO2, and determinants of acid-base state (protein, electrolytes, and PCO2). Results: Increased VO2 during exercise was facilit...
Ravis WR, Duran SH, Pedersoli WM, Schumacher J.The pharmacokinetics of phenobarbital were determined in six mature horses after a single oral dose. Horses were administered a 5.5 mg/kg of body weight oral dose of phenobarbital tablets. Based on the combined evaluation of i.v. and oral results, phenobarbital displayed two-compartment pharmacokinetics in the horse with a terminal half-life of 19.0 +/- 4.4 (mean +/- SD) h. This half-life is considerably shorter than those reported for dogs and humans. The steady-state volume of distribution (Vdss/F) and the total body clearance (Clt/F) of phenobarbital were 0.753 +/- 0.115 l/kg and 27.9 +/- 9...
Naylor JM.Hyperkalemic periodic paralysis is an autosomal codominant genetic disease of horses who are descendants of the quarter horse sire Impressive. It produces a muscular phenotype that has been selected by show judges, which has resulted in the rapid dissemination of this disease. Clinical attacks are characterized by muscle fasciculation and spasm, and they respond to treatments for the concurrent hyperkalemia.
Beard W.To describe parainguinal laparocystotomy for urolith removal and to report outcome. Methods: Prospective clinical study. Methods: Ten geldings with uroliths. Methods: Signalment, number, size, type of uroliths, surgical technique, and complications were recorded. Long-term follow-up was obtained by telephone interviews with the client and/or examination by the referring veterinarian. Results: Cystic calculi, 3-9 cm in diameter, were removed by parainguinal laparocystotomy. Mean surgical time was 59 minutes (range, 40-100 minutes). With this approach, ligation of the pudendal or superficial epi...
Starzonek J, Roscher K, Blüher M, Blaue D, Schedlbauer C, Hirz M, Raila J, Vervuert I.In horses and ponies numerous medical conditions are known to be linked with inflammation in different tissues, especially in the liver. Besides affecting other metabolic pathways such as the expression of certain interleukins (IL), inflammation is associated with stress of the endoplasmic reticulum (ER). In particular, ER stress leads to adaptive stress response and can be measured by several markers of inflammatory and stress signalling pathways, like nuclear factor κB (NF-kB). Objective: To investigate lipopolysaccharide (LPS)-induced inflammatory reactions and their modulation in horses a...
Tzipori S, Withers M, Hayes J, Robins-Browne R, Ward KL.Equine small intestinal brush-border membranes, from 40 adult horses were tested in vitro for the presence of receptors for the Escherichia coli adhesive antigens K88ab, K88ac and K99. Only K88-positive strains of E. coli adhered strongly to horse brush-border membranes. In contrast, a K88-negative mutant strain J2, 2 K99-positive strains and 3 E. coli strains isolated from foals failed to adhere to horse brush-border membranes. Purified K88ac pili when reacted with equine brush-border membranes inhibited to a great extent the adhesion of K88-positive E. coli. Similarly, K88-positive E. coli p...
Hurcombe SD, Scott VH.To determine whether direct intra-abdominal pressures (IAP) and calculated direct abdominal perfusion pressures (APP) are location dependent within the abdomen of standing horses. We hypothesize that IAP will be increased and calculated APP will be decreased at a ventral abdominal location (V) when compared to values obtained from the left (LFl) or right flank (RFl). Methods: Prospective experimental design. Methods: University-based equine research facility. Methods: Seven healthy adult horses, 4 geldings and 3 mares. Methods: Measurements of direct IAP obtained from the RFl, LFl, and V locat...
Belyaev RI, Kuznetsov AN, Prilepskaya NE.The vertebral column is a hallmark of vertebrates; it is the structural basis of their body and the locomotor apparatus in particular. Locomotion of any vertebrate animal in its typical habitat is directly associated with functional adaptations of its vertebrae. This study is the first large-scale analysis of mobility throughout the presacral region of the vertebral column covering a majority of extant odd-toed ungulates from 6 genera and 15 species. In this study, we used a previously developed osteometry-based method to calculate available range of motion. We quantified all three directions ...
Winder NC, von Fellenberg R.The peroxidase anti-peroxidase technique was used to demonstrate free and intracellular immunoglobulin (Ig) within the lungs of 23 horses with chronic small airway disease. Histologically, all the horses had chronic bronchiolitis; however, the lesions varied in degree from mild in eight horses, to moderate in nine horses and severe in six horses. Lungs from three horses which had no gross or histopathological lesions were used as controls. In comparison with control horses, horses with mild chronic bronchiolitis had increased numbers of Ig A-containing and non-immunoglobulin staining cells aro...
Zaitseva S, Dagurova O, Radnagurueva A, Kozlova A, Izotova A, Krylova A, Noskov S, Begmatov S, Patutina E, Barkhutova DD.The Buryatian horse is an ancient breed and, as an indigenous breed, they have unique adaptive abilities to use scarce pastures, graze in winter, and survive in harsh conditions with minimal human care. In this study, fecal microbiota of Buryatian horses grazing in the warm and cold seasons were investigated using NGS technology on the Illumina MiSeq platform. We hypothesized that the composition of microbial communities in the feces of horses maintained on pasture would change in the different seasons, depending on the grass availability and different plant diets. We conducted microhistologic...
Agass R, Dixon J, Fraser B.Pre-surgical investigation of digital flexor tendon sheath pathology remains challenging with current standard imaging techniques. The aim of this prospective, anatomical, pilot study was to describe the anatomy of the equine hind limb digital flexor tendon sheath using a combination of computed tomography (CT) and computed tomographic contrast tenography in clinically normal cadaver limbs. Ten pairs of hind limbs with no external abnormalities were examined from the level of the tarsometatarsal joint distally. Limbs initially underwent non-contrast CT examination using 120 kVp, 300 mAs, and...
Kovacs S, Racz B, Sotonyi P, Bakos Z.Atrial fibrillation is the most common arrhythmia in horses causing poor performance. The role of pulmonary vein triggers in the pathogenesis has been identified in horses. Ablation methods have been investigated, but the available information on anatomical, histological and immunohistochemical assessment of the pulmonary vein ostia and the conduction system of the myocardial sleeve is still limited. Objective: The aim of the study was to describe the morphological properties of the myocardial sleeve in healthy horses. Methods: Cross-sectional. Methods: Eighty-three equine hearts were dissecte...
Coad CT, Robinson NM, Wilhelmus KR.We evaluated 31 fungal specimens obtained from equine corneas over a 10-year period, 1973 to 1983. More than half were received in late summer and early autumn, and the number tended to increase in frequency during the 1980s. These isolates included 13 different genera and 20 different species. The prevalent genus was Aspergillus (35%). On the basis of examinations for tube-dilution minimal inhibitory concentrations and minimal fungicidal concentrations of 16 fungal isolates, the imidazole antibiotics such as miconazole and ketoconazole consistently showed the lowest geometric mean titers for ...
Aguiar FLN, Gastal GDA, Ishak GM, Gastal MO, Teixeira DIA, Feugang JM, Figueiredo JR, Gastal EL.The effect of FSH supplementation on an enriched cultured medium containing insulin (10 ng/mL) and EGF (50 ng/mL) was investigated on in vitro culture of equine ovarian biopsy tissue. Ovarian tissue fragments were collected from mares (n = 10) and distributed in the following treatments: noncultured control, cultured control, and cultured + FSH. Both treated groups were cultured for 7 or 15 days. The end points evaluated were: follicular morphology, estradiol levels in the culture medium, fluorescence intensity for TUNEL, EGFR and Ki-67 detection, and gene expression of GDF-9, BMP-15, a...
Cauvin ER, Munroe GA, Boyd JS, Paterson C.The aim of this study was to determine the normal ultrasonographic features of the cranial and caudal aspects of the femorotibial articulation and, in particular, to establish a method of examining the menisci, cruciate and meniscal ligaments ultrasonographically. Twenty hindlimbs isolated post mortem from 10 horses were used to study the normal ultrasonographic and gross anatomy of the femorotibial joint. Five stifles from 3 normal, live horses were also examined with B-mode, real-time ultrasound imaging. The results of the anatomical study are presented. The joint surfaces, menisci, cruciate...
Aufox EE, Frank LA, May ER, Kania SA.Dermatophilus congolensis is a facultative anaerobic actinomycete that causes papular to exudative dermatitis with crusting in horses. This organism is frequently implicated as a cause of pastern dermatitis, but few data are available validating the organism's association with this disease. Objective: The aim of this study was to evaluate if D. congolensis is associated with pastern dermatitis in horses utilizing RT-qPCR. Methods: Fifteen client-owned horses diagnosed with pastern dermatitis and eight client-owned unaffected control horses were utilized for this study. Methods: A cross-sectio...
Wong JKY, Chan GHM, Choi TLS, Kwok KY, Lau MY, Leung GNW, Wan TSM, Ho ENM.A high-throughput method has been developed for the doping control analysis of 124 drug targets, processing up to 154 horse urine samples in as short as 4.5 h, from the time the samples arrive at the laboratory to the reporting deadline of 30 min before the first race, including sample receipt and registration, preparation and instrument analysis and data vetting time. Sample preparation involves a brief enzyme hydrolysis step (30 min) to detect both free and glucuronide-conjugated drug targets. This is followed by extraction using solid-supported liquid extraction (SLE) and analysis using liq...
Elsheikha HM, Mansfield LS.Sarcocystis neurona has become recognized as the major causative agent of equine protozoal myeloencephalitis (EPM) in the Americas. At least 3 pathogenic species of Sarcocystis, including S. neurona, can be isolated from opossums. Methods are needed to ascertain whether these isolates are viable and capable of causing infections. In this study, the nuclear stain propidium iodide (PI) was used to differentiate between live (viable) and heat-killed (nonviable) S. neurona sporocysts. PI was excluded by live sporocysts but penetrated compromised sporocyst membrane and stained sporozoite nuclei of ...
