"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.
Wilkins PA.Rapid evaluation and intervention is a requirement and a characteristic of patient management in neonatal intensive care units, and this applies for equine neonates also. Appropriate interventions are based on solid knowledge of age, maturity, and species-specific differences in reference ranges. Point-of-care (POC) testing devices speedup decision making regarding treatments and interventions. However, there are potential limitations of these devices when applied to age groups and species beyond those they were specifically developed for. This article discusses the age-specific differences in...
Almeida J, Conley AJ, Mathewson L, Ball BA.In the mammalian testis, Leydig cells are primarily responsible for steroidogenesis. In adult stallions, the major endocrine products of Leydig cells include testosterone and estrogens. 3β-hydroxysteroid dehydrogenase/Δ(5)-Δ(4)-isomerase (3βHSD) and 17α-hydroxylase/17,20-lyase (P450c17) are two key steroidogenic enzymes that regulate testosterone synthesis. Androgens produced by P450c17 serve as substrate for estrogen synthesis. The aim of this study was to investigate localization of the steroidogenic enzymes P450c17, 3βHSD, and P450arom and to determine changes in expression during dev...
Soboll Hussey G, Hussey SB, Wagner B, Horohov DW, Van de Walle GR, Osterrieder N, Goehring LS, Rao S, Lunn DP.Equine herpesvirus-1 (EHV-1) infection remains a significant problem despite the widespread use of vaccines. The inability to generate a protective immune response to EHV-1 vaccination or infection is thought to be due to immunomodulatory properties of the virus, and the ORF1 and ORF2 gene products have been hypothesized as potential candidates with immunoregulatory properties. A pony infection study was performed to define immune responses to EHV-1, and to determine if an EHV-1 ORF1/2 deletion mutant (ΔORF1/2) would have different disease and immunoregulatory effects compared to wild type EH...
Schauer SN, Briant C, Ottogalli M, Decourt C, Handel IG, Donadeu FX.This study was conducted to test the hypothesis that supplementation of growing follicles with LH during the early spring transitional period would promote the development of steroidogenically active, dominant follicles with the ability to respond to an ovulatory dose of hCG. Mares during early transition were randomly assigned to receive a subovulatory dose of equine LH (in the form of a purified equine pituitary fraction) or saline (transitional control; n = 7 mares per group) following ablation of all follicles >15 mm. Treatments were administered intravenously every 12 h from the day th...
Goretti RG, Araújo RR, Filho AN, Araújo GH, Lopes EP, Guimarães JD.The objective was to evaluate the effects of giving prostaglandin F₂(α) (PGF) to donor mares 48 h prior to embryo collection. Non-lactating donor mares (n = 20 estrous cycles in 10 mares), ranging from 2.5 to 10 y of age and 400 to 500 kg of body weight were used from September 2004 to February 2005 in the southern hemisphere (Brazil). Donor mares were randomly assigned in a cross-over design study. During a Treated cycle, 7.5 mg PGF was given 48 h prior to embryo collection, whereas in the Control cycle, 7.5 mg PGF was given at embryo collection. In Treated Cycles, serum progesterone conce...
Singh BR, Gulati BR, Virmani N, Chauhan M.At a thoroughbred equine breeding farm near Hissar (Haryana), three mares aborted in their seventh month of pregnancy. The vaginal swabs of all aborted mares, and stomach contents, heart blood, liver, spleen and placenta of aborted fetuses yielded pure culture of Aeromonas hydrophila. In addition, A. hydrophila was also isolated from the vaginal swabs of three repeat breeding mares and faecal sample of a diarrheic foal. The source of infection was possibly water supply as all the water samples collected from taps, mother tank and storage tank were found to be positive for A. hydrophila. The an...
Sanz MG, Wills TB, Christopherson P, Hines MT.A 17-year-old Peruvian Paso mare was evaluated for bilateral epistaxis that had been present for at least 3 years. The mare had mild anemia, platelet count within the reference interval, unremarkable coagulation times, and a negative Coggins test. On endoscopic examination, structural abnormalities were not observed in the nasal cavities, pharynx, larynx, trachea, or either guttural pouch, but petechiation was noted in the nasal mucosa. Additional tests revealed prolonged cutaneous bleeding time, normal concentration of von Willebrand factor antigen, an abnormal clot retraction test, and failu...
Romero AE, Rodgerson DH.Diaphragmatic rent and visceral herniation in the horse is seldom diagnosed, but historically carries a poor prognosis. The objective of this study was to document the presentation and surgical management of all diaphragmatic rents as presented to 2 referral institutions over a 5-year period. A review of 31 cases demonstrated that even with advances in surgical management of abdominal and thoracic conditions, little has been done to change the prognosis for this condition. Success rate was 23% for all horses presented for colic and were ultimately diagnosed with a diaphragmatic hernia, and 46%...
Berzina I, Trumble NS, Novicki T, Sharkey LC.An 11-year-old American Saddlebred gelding was presented for evaluation of a nonpainful subconjunctival mass involving the lateral canthus of the left eye. Other findings included a central corneal scar and a small central cataract of the lens in the left eye. Fine-needle aspiration of the mass was performed and cytologic examination revealed marked pyogranulomatous inflammation with intralesional fungal hyphae, consistent with mycetoma. The fungal structures were elongated and characterized by nonstaining walls; several bulbous yeast-like structures were also observed. The mycetoma was surgic...
Marshall JF, Bhatnagar AS, Bowman SG, Howard CM, Morris NN, Skorich DA, Redding CD, Blikslager AT.To determine the cyclooxygenase (COX) selectivity of robenacoxib and its effect on recovery of jejunal mucosa following ischemic injury in horses. Methods: 12 healthy horses. Methods: Half the maximal inhibition (EC₅₀) of robenacoxib for COX-1 and COX-2 activity was established in bloods samples from 6 horses via measurement of thromboxane B₂ (TXB₂) and prostaglandin E₂ concentrations, respectively; COX selectivity was subsequently calculated. Six other horses were anesthetized, and ischemia was induced in the jejunum for 2 hours. Control and ischemia-injured mucosa were collected an...
Imai DM, Barr BC, Daft B, Bertone JJ, Feng S, Hodzic E, Johnston JM, Olsen KJ, Barthold SW.Lyme neuroborreliosis--characterized as chronic, necrosuppurative to nonsuppurative, perivascular to diffuse meningoradiculoneuritis--was diagnosed in 2 horses with progressive neurologic disease. In 1 horse, Borrelia burgdorferi sensu stricto was identified by polymerase chain reaction amplification of B burgdorferi sensu stricto-specific gene targets (ospA, ospC, flaB, dbpA, arp). Highest spirochetal burdens were in tissues with inflammation, including spinal cord, muscle, and joint capsule. Sequence analysis of ospA, ospC, and flaB revealed 99.9% sequence identity to the respective genes in...
de Laat MA, Kyaw-Tanner MT, Nourian AR, McGowan CM, Sillence MN, Pollitt CC.Metalloproteinases have been implicated in the pathogenesis of equine laminitis and other inflammatory conditions, through their role in the degradation and remodelling of the extracellular matrix environment. Matrix metalloproteinases (MMPs) and their inhibitors are present in normal equine lamellae, with increased secretion and activation of some metalloproteinases reported in horses with laminitis associated with systemic inflammation. It is unknown whether these enzymes are involved in insulin-induced laminitis, which occurs without overt systemic inflammation. In this study, gene expressi...
Fernandes F, Chen K, Ehrlich LS, Jin J, Chen MH, Medina GN, Symons M, Montelaro R, Donaldson J, Tjandra N, Carter CA.Phosphatidylinositol 4,5-biphosphate [PI(4,5)P(2) ], the predominant phosphoinositide (PI) on the plasma membrane, binds the matrix (MA) protein of human immunodeficiency virus type 1 (HIV-1) and equine infectious anemia virus (EIAV) with similar affinities in vitro. Interaction with PI(4,5)P(2) is critical for HIV-1 assembly on the plasma membrane. EIAV has been shown to localize in internal compartments; hence, the significance of its interaction with PI(4,5)P(2) is unclear. We therefore investigated the binding in vitro of other PIs to EIAV MA and whether intracellular association with comp...
Rudi K.Mainly due to the lack of time-series data, we know very little about the underlying interactions leading to adverse states in the gut. I therefore investigate the host-bacteria dynamic interactions in a recently published acidotic state induction time-series experiment. Too high levels of fermentation in the hindgut may lead to elevated serum lactate levels, which is a characteristic of the acidotic state. The acidotic state was induced through injection of oligofructose directly into the caecum of five horses, with subsequent temporal measurements of host serum lactate, and a range of caecum...
Zoonoses and public healthFebruary 1, 2011
Volume 58, Issue 7 514-518 doi: 10.1111/j.1863-2378.2011.01394.x
Adaszek Ł, Winiarczyk S.This study was aimed at determining the cause of the diseases in five horses exhibiting symptoms of fever, joint oedema and ataxia and thrombocytopenia. The PCR technique revealed the presence in the blood of 16S RNA Anaplasma/Ehrlichia spp. genetic material. DNA amplification with primers EHR 521 and EHR 747 gave a product with a size of 247 bp. The sequence of the PCR product obtained showed a 97.6-99.6% similarity with a sequence of a fragment of 16S RNA Anaplasma phagocytophilum, gene number EU 090186 from GenBank. Intravenous administration of oxytetracycline at a dose of 8 mg/kg of body ...
Hart KA, Barton MH, Ferguson DC, Berghaus R, Slovis NM, Heusner GL, Hurley DJ.Relative cortisol insufficiency occurs in septic foals and impacts survival. Serum free (biologically available) cortisol concentration might be a better indicator of physiologic cortisol status than serum total cortisol concentration in foals. Objective: In septic foals, (1) low free cortisol concentration correlates with disease severity and survival and (2) predicts disease severity and outcome better than total cortisol concentration. Methods: Fifty-one septic foals; 11 healthy foals; 6 healthy horses. Methods: In this prospective clinical study, foals meeting criteria for sepsis at admiss...
Lavoie JP, Cesarini C, Lavoie-Lamoureux A, Moran K, Lutz S, Picandet V, Jean D, Marcoux M.There is limited information relating bronchoalveolar lavage (BAL) cytology and cytokine messenger ribonucleic acid (mRNA) expression in racehorses with inflammatory airway disease (IAD). HYPOTHESIS AND OBJECTIVE: We hypothesize that cytokine expression in BAL cells would correlate with cytology. Thus, we evaluated the mRNA expression of selected cytokines in BAL cells in racehorses with exercise intolerance and lower airway inflammation. Methods: Thirty-one client-owned Standardbred racehorses with exercise intolerance. Methods: Prospective, observational study. Cells were obtained by BAL, an...
Nagy A, Dyson S.Cadaver carpi of 30 mature horses with no history of carpal or proximal metacarpal pain were examined using low-field (0.27 T) and high-field (1.5 T) magnetic resonance imaging (MRI). Normal MRI anatomy in transverse, sagittal, and dorsal plane images was determined by comparison with anatomical specimens and standard texts. Subchondral bone and cortical bone thickness measurements were obtained from standardised sites. There was variable subchondral bone thickness in the radius and carpal bones; subchondral bone thickness was consistently larger at dorsal compared with palmar sites in the...
Norton JL, Nolen-Walston RD, Underwood C, Slack J, Boston R, Dallap BL.Central venous pressure (CVP) customarily has been measured in veterinary patients with water manometry. However, many institutions are now using stallside electronic monitors in both anesthesia and intensive care units for many aspects of patient monitoring. Objective: Electronic stall side monitoring devices will agree with water manometry for measurement of CVP in horses. Methods: Ten healthy adult horses from the university research herd. Methods: Central venous catheters were placed routinely, and measurements were obtained in triplicate with each of the 3 methods every 12 hours for 3 day...
Gille C, Kayser M, Spiller A.Whereas in former times horses were reserved primarily for people involved in agriculture, elite equestrians or the military, nowadays equestrian sport has become an activity for people with a wide variety of backgrounds. However, as more and more people become involved with equestrian sport today, the knowledge concerning animal husbandry in general is diminishing due to an alienation from agricultural themes in modern societies. As a consequence, this development affects both riding ability and the appraisal of horses, especially with respect to the purchase of horses. In order to analyse wh...
Beekman L, Tohver T, Dardari R, Léguillette R.The stability of reference genes has a tremendous effect on the results of relative quantification of genes expression by quantitative polymerase chain reaction. Equine Inflammatory Airway Disease (IAD) is a common condition often treated with corticosteroids. The diagnosis of IAD is based on clinical signs and bronchoalveolar lavage (BAL) fluid cytology. The aim of this study was to identify reference genes with the most stable mRNA expression in the BAL cells of horses with IAD irrespective of corticosteroids treatment. Results: The expression stability of seven candidate reference genes (B2...
Baumann C, Daly CM, McDonnell SM, Viveiros MM, De La Fuente R.Pairing of the sex chromosomes during mammalian meiosis is characterized by the formation of a unique heterochromatin structure at the XY body. The mechanisms underlying the formation of this nuclear domain are reportedly highly conserved from marsupials to mammals. In this study, we demonstrate that in contrast to all eutherian species studied to date, partial synapsis of the heterologous sex chromosomes during pachytene stage in the horse is not associated with the formation of a typical macrochromatin domain at the XY body. While phosphorylated histone H2AX (γH2AX) and macroH2A1.2 are pres...
Hébert L, Moumen B, Duquesne F, Breuil MF, Laugier C, Batto JM, Renault P, Petry S.Taylorella equigenitalis is the causative agent of contagious equine metritis (CEM), a sexually transmitted infection of horses. We herein report the genome sequence of T. equigenitalis strain MCE9, isolated in 2005 from the urethral fossa of a 4-year-old stallion in France.
Suontama M, van der Werf JH, Juga J, Ojala M.Genetic correlations for body measurements and subjectively scored traits between foals and studbook horses were estimated using bivariate linear mixed models. Observations for nine foal and eleven studbook traits in Finnhorses on 6529 foals and 6596 studbook horses and in Standardbred trotters on 3069 foals and 2112 studbook horses were available from the Finnish horse breeding shows. The number of sires with progeny in both foal and studbook data was 203 in Finnhorse and 145 in Standardbred trotters. Estimates of heritability for body measurements in foals and studbook horses using univariat...
Watts AE, Yeager AE, Kopyov OV, Nixon AJ.Tendon injury is a common problem in athletes, with poor tissue regeneration and a high rate of re-injury. Stem cell therapy is an attractive treatment modality as it may induce tissue regeneration rather than tissue repair. Currently, there are no reports on the use of pluripotent cells in a large animal tendon model in vivo. We report the use of intra-lesional injection of male, fetal derived embryonic-like stem cells (fdESC) that express Oct-4, Nanog, SSEA4, Tra 1-60, Tra 1-81 and telomerase. Methods: Tendon injury was induced using a collagenase gel-physical defect model in the mid-metacar...
Baird JD, Valberg SJ, Anderson SM, McCue ME, Mickelson JR.The purpose of this study was to determine which continental European draught horse breeds harbour a mutation in the glycogen synthase 1 gene (GYS1) that is known to be responsible for type 1 polysaccharide storage myopathy in quarter horses and North American draught horses. Of a non-random selection of continental European draught horses belonging to 13 breeds, 62 per cent (250 of 403) tested were found to carry the mutant allele. The horses were located in Belgium, France, Germany, The Netherlands, Spain and Sweden. The mutation was identified in animals from each of the breeds examined. In...
Forster HV, Lowry TF, Pan LG, Erickson BK, Korducki MJ, Forster MA.We determined the effect of pulmonary vagal (hilar nerve) denervation (HND) and diaphragm deafferentation (DD) on inspiratory load compensation. We studied awake intact (I; n = 10), DD (n = 5), HND (n = 4), and DD+HND (n = 7) ponies at rest and during mild (1.8 mph, 5% grade) and moderate (1.8 mph, 15% grade) treadmill exercise before, during, and after resistance of the inspiratory circuit was increased from approximately 1.5 to approximately 20 cmH2O.l-1.s. During the first loaded breath in I ponies at rest, inspiratory time (TI) increased, expiratory time decreased, and inspiratory drive in...
Hamm D, Turchi P, Jöchle W.In a double blind study, eight horses were treated intravenously at seven-day intervals with detomidine at doses of 10, 20 and 40 micrograms/kg, or with romifidine at doses of 40, 80 and 120 micrograms/kg, or with a placebo solution. Their sedative and analgesic effects were evaluated by objective measurements and by a clinician at 15-minute intervals for three hours and the horses' instability in stocks, locomotor ataxia and heart rate were recorded simultaneously. The administration of both drugs at all doses resulted in sedation. The sedation achieved with romifidine was significantly shall...
Herholz C, Tschudi P, Gerber H, Moens Y, Straub R.A new computerised ultrasound-based spirometry system according to Buess et al. (1995) modified by a double flow measurement facility was used to study pulmonary function in healthy horses and horses affected with subclinical and manifest chronic bronchiolitis (CB). The horses were first evaluated at rest without any medication. On another occasion all horses were tested following i.v. administration of xylazine (0.4 mg/kg) and following i.v. administration of lobeline hydrochloride (l.hy.; 0.2 mg/kg) to evaluate the effect of xylazine and l.hy. on different spirometric variables. Ultrasound-b...
Hussein H, Boyaka P, Dulin J, Russell D, Smanik L, Azab M, Bertone AL.Selective inhibition of Cathepsin K (CatK) has a promising therapeutic potential for diseases associated with bone loss and osseous inflammation, such as osteoarthritis, periodontitis, and osteoporosis. In horses, stress-related bone injuries are common and accompanied by bone pain and inflammation resulting in excessive bone resorption and periostitis. VEL-0230 is a highly selective inhibitor of CatK that significantly decreased bone resorption and increased bone formation biomarkers. The goal of this study was to demonstrate the presence of CatK in equine bone and a simultaneous influence on...
Ogilvie TH, Rosendal S, Blackwell TE, Rostkowski CM, Julian RJ, Ruhnke L.Mycoplasma felis was the only organism recovered from the thoracic cavity of a horse with pleuritis. Large numbers of mildly degenerative neutrophils were in the pleural fluid. The horse developed a serologic response to M felis and recovered during hospitalization. Experimentally, a pony was inoculated in the thoracic cavity with a pure culture of the M felis isolate suspended in the pony's serum. A control pony was inoculated with serum only. Within 48 hours, the principal pony developed fever, increased respiratory rate, pleural effusion, and signs of pain. A highly cellular exudate with no...
Scheurer L, Bachofen C, Herteman N, Hilbe M, Wolfer N, Schoster A.This case series describes three cases of equine multinodular pulmonary fibrosis (EMPF) diagnosed at the Clinic for Equine Internal Medicine at the University of Zurich between 2012 and 2017. Current information on etiology and treatment options are presented. Two horses showed mild signs of chronic lower respiratory tract disease and one horse was presented with acute signs of disease including recurrent fever spikes and tachypnea. Diagnosis was achieved by physical examination, radiographic findings, and PCR testing for equine herpesviruses (EHV) of bronchoalveolar lavage (BAL) fluid or lung...
Lee GKC, Tessier L, Bienzle D.The Salivary Scavenger and Agglutinin (SALSA) protein is an innate immune protein with various alleged functions, including the regulation of inflammation and tissue remodeling. Transcriptomic studies of severe equine asthma (SEA) showed downregulation of the gene encoding SALSA in bronchial epithelium of asthmatic compared to non-asthmatic horses. This study aimed to characterize expression of SALSA in equine tissues by immunohistochemistry (IHC), corroborate potential differences in epithelial gene expression between asthmatic and non-asthmatic horses, and assess the structure of equine SALS...
Bellei MH, Kerr C, McGurrin MK, Kenney DG, Physick-Sheard P.To describe management of anesthesia for transvenous electrical cardioversion (TVEC) in horses and report perianesthetic complications. Methods: Retrospective case series. Methods: 62 horses with atrial fibrillation and without underlying cardiac disease and 60 horses without atrial fibrillation. Methods: Medical records of horses with atrial fibrillation anesthetized for TVEC were reviewed, as were records of horses without atrial fibrillation anesthetized for magnetic resonance imaging (MRI). The TVEC group horses were compared with MRI group horses for incidence of intraoperative bradycardi...
Dietrich J, Handschuh S, Steidl R, Böhler A, Forstenpointner G, Egerbacher M, Peham C, Schöpper H.As the longissimus dorsi muscle is the largest muscle in the equine back, it has great influence on the stability of the spine and facilitates proper locomotion. The longissimus muscle provides support to the saddle and rider and thereby influences performance in the horse. Muscular dysfunction has been associated with back disorders and decline of performance. In general, muscle function is determined by its specific intramuscular architecture. However, only limited three-dimensional metrical data are available for the inner organisation of the equine longissimus dorsi muscle. Therefore, we a...
Peng Z, Shen D, Zhang D, Li X, Wang L, Zhai Q, Hou Z, Li H.The equine Parascaris spp. is large, parasitic nematodes, and predominantly focuses on the intestine of foals and young weanlings. There are two roundworms, Parascaris equorum and Parascaris univalens, recognized among equine hosts. In this study, all fifty-nine Parascaris worms were harvested from three different equine hosts (twenty specimens from Equus zebra, twenty specimens from E. caballus, and nineteen specimens from E. asinus). The ribosomal gene (ITS) and mitochondrial genes (cox1 and nadh1) were amplified to identify and genetically characterize these worms. Analysis of ITS sequences...
Holmes JM, Gilkerson JR, El Hage CM, Slocombe RF, Muurlink MA.A 5-year-old Thoroughbred mare presented with signs of severe pain and was taken to exploratory laparotomy based on suspicion of an acute abdominal lesion. A mild gastrointestinal lesion was discovered, but was considered disproportional to the severity of signs displayed. The mare was later euthanased because of intractable pain. Comprehensive postmortem examination, including polymerase chain reaction testing of central nervous system tissue samples, allowed a definitive diagnosis of Murray Valley encephalomyelitis to be made. This case demonstrates the variability of clinical presentations ...
Ryhner T, Müller N, Balmer V, Gerber V.The mechanisms leading to mucus accumulation in equine inflammatory airway disease (IAD) and recurrent airway obstruction (RAO) are unclear. In airways of human patients with asthma and/or chronic obstructive pulmonary disease as well as in animal models of these diseases, associations of mucus hyperproduction with increased calcium-activated chloride channel 1 (CLCA1), epidermal growth factor receptor (EGFR), mucin 5AC (MUC5AC), B-cell lymphoma 2 (Bcl-2), interleukin (IL)-13 and interferon (IFN)-gamma expression have been reported. We hypothesized that increased mucus accumulation in RAO and ...
Honnens A, Weisser S, Welter H, Einspanier R, Bollwein H.The objective of this study was to investigate the relationships between uterine perfusion and estrogen, progesterone and the uterine nitric oxide synthase (NOS) system in five trotter mares during the estrous cycle. Color Doppler sonography for measurement of uterine blood flow and collection of blood for determination of plasma estrogen and progesterone concentrations were performed on days 0 (= ovulation), 1, 5, 11 and 15 and daily during estrus (days -1 to -4) of one estrous cycle; endometrial biopsy collection for mRNA expression analysis of NOS and estrogen receptors was performed on day...
Christmann U, Hite RD, Witonsky SG, Elvinger F, Werre SR, Thatcher CD, Tan RH, Buechner-Maxwell VA.Surfactant alterations are described in horses after exercise, anesthesia, and prolonged transport, in horses with recurrent airway obstruction, and in neonatal foals. The effect of horse age or bronchoalveolar lavage fluid (BALF) sample characteristics on surfactant is unknown. Objective: To evaluate surfactant phospholipid composition and function in healthy horses, and to investigate the influence of age and BALF sample characteristics on surfactant. Methods: Seventeen healthy horses 6-25 years of age maintained on pasture year-round. Methods: BALF was collected by standard procedures and w...
Greene CE, Tsang VC, Prestwood AK, Meriwether EA.Optimal reaction conditions for the activated partial thromboplastin time (APTT), 1-stage prothrombin time (PT), and Russell's viper venom time were studied for pooled plasmas of horses, cattle, sheep, goats, swine, dogs, cats, and persons. Changes in CaCl2 and NaCl concentrations had significant effects on the APTT and PT reactions. The APTT was more sensitive than the PT to changes in CaCl2 concentration. The CaCl2 concentration recommended by the manufacturer for the APTT was suboptimal for some of plasmas of domesticated animals in ths study. Infusorial earth (Celite, activator) concentrat...
Schmitz A, Thormann W, Moessner L, Theurillat R, Helmja K, Mevissen M.Ketamine, an injectable anesthetic and analgesic consisting of a racemic mixture of S-and R-ketamine, is routinely used in veterinary and human medicine. Nevertheless, metabolism and pharmacokinetics of ketamine have not been characterized sufficiently in most animal species. An enantioselective CE assay for ketamine and its metabolites in microsomal preparations is described. Racemic ketamine was incubated with pooled microsomes from humans, horses and dogs over a 3 h time interval with frequent sample collection. CE data revealed that ketamine is metabolized enantioselectively to norketamine...
Kawai S, Igarashi I, Abgaandorjiin A, Ikadai H, Omata Y, Saito A, Nagasawa H, Toyoda Y, Suzuki N, Matsuda H.In-vitro-propagated Babesia caballi parasites were examined by scanning and transmission electron microscopy. Many small pores were observed over the entire surface of infected erythrocytes on scanning electron microscopy, and on transmission electron microscopy these small pores were found to be openings of tubular structures. By the examination of a number of infected cells the tubular structures were found to be connected with the parasite, and this observation might indicate that the tubular structures arose the edge of the parasite and terminated at an Invagination on the surface of the e...
Zaha C, Schuszler L, Dascalu R, Nistor P, Florea T, Imre K, Rujescu C, Sicoe B, Igna C.Horses with palmar foot pain do not show a typical increase in temperature in the palmar aspect of the hoof and heel due to low blood flow. The objectives of the current study were to determine the changes and differences in the thermographic pattern of the sole surface in horses with unilateral palmar foot pain and non-lame horses before and after training. We hypothesized that the thermal pattern and the local temperature of the frog area and toe area would be similar, with an increased local temperature after training in both lame and non-lame horses. A pilot study was conducted to investig...
Figueredo LA, Cafarchia C, Otranto D.Fungi of the genus Geotrichum are commonly found in the environment and, in some circumstances, they may cause diseases in humans and animals. Although these fungi have been isolated from skin lesions of some animal species, their pathogenic role in horses remains uncertain. With the aim to investigate the role of Geotrichum candidum as etiological agent of dermatomycoses, a retrospective study of 64 horses presenting skin lesions and suspected to have fungal infections was carried out. For each animal, anamnestic data were recorded and fungal culture were performed using hair. Out of 64 cases...
Robinson JA, Allen GK, Green EM, Fales WH, Loch WE, Wilkerson CG.Fourteen mares and their foals were attended at parturition. After mare-foal bonding, 8 colostrum-deprived (CD) foals were removed from their dams, deprived of colostrum, and provided with an alternative milk source for the first 24 h of life. The mares were milked out every 2-4 h during this period to remove colostrum, after which the CD foals were returned to their mares and allowed to nurse. Six colostrum-fed (CF) foals were allowed to suck colostrum in the normal manner. Foal serum IgG concentration was determined by single radial immunodiffusion (means, CD = 0 mg/dl; CF = 1,508 mg/dl). Ac...
Roberts HA, Hurcombe SD, Hillier A, Lorch G.House dust mite (HDM) and storage mite (SM) stable fauna and their associated equine intradermal test (IDT) threshold concentrations (TCs) for the midwestern region of the USA are unknown. Objective: To determine IDT TCs and serum IgE concentrations for two HDM and three SM species in clinically normal horses over two seasons, and to identify the mite taxa and habitats in a stable. Methods: Thirty-eight clinically normal horses. Methods: Threshold concentrations for HDMs and SMs were determined using IDT subjective measurements and a statistical model. An enzyme-linked immunosorbent assay was ...
Higson FK, Jones OT.The exposure of animal neutrophils to crystals implicated in joint inflammation induces superoxide and peroxide generation in a concentration and temperature dependent fashion. Active crystals were urate, hydroxyapatite, pyrophosphate and brushite; diamond and cholesterol were inactive. Cytochalasin B increased superoxide yield after addition of brushite, and inhibitors of the PMA induced respiratory burst blocked the crystal induced response. Addition of urate to anaerobic neutrophils causes the reduction of a b-type cytochrome, a likely component of the neutrophil superoxide generating syste...
Wang JL, Zhou DH, Chen J, Liu GX, Pu WB, Liu TY, Qin SY, Yin MY, Zhu XQ.Toxoplasmosis is a worldwide zoonosis caused by Toxoplasma gondii, which can infect warm-blooded animals and humans. The present study was performed to investigate the seroprevalence of T. gondii in horses in Xinjiang, northwestern China. A total of 637 blood samples were collected from seven regions in Changji Hui Autonomous Prefecture, Xinjiang in 2011 and assayed for T. gondiiantibodies using the modified agglutination test (MAT). Risk factors (age, gender, and region) related to seroprevalence were determined by a multivariate logistic regression analysis. A total of 200 horses (31.4%, 95%...
Vivrette SL, Sellon DC, Gibbons DS.Diagnosis of pneumonia caused by Rhodococcus equi can be made more rapidly by use of a polymerase chain reaction (PCR) assay than by use of conventional bacteriologic culture techniques. Use of a PCR assay aids in the differentiation between virulent and avirulent strains of R equi, and the assay may be used to identify R equi in feces and soil of breeding farms.
Rubio-Martínez L, López-Sanromán J, Cruz AM, Santos M, San Román F.To study the pharmacokinetics of vancomycin in plasma obtained from the medullary sinusoids of the proximal phalanx (P1) after intravenous (IV) and intraosseous (IO) regional limb perfusion (RLP). Methods: Experimental study. Methods: Twelve horses. Methods: IV and IO RLP were performed in 2 groups (n = 6) of horses. Vancomycin hydrochloride (300 mg in 60 mL 0.9% NaCl) was randomly infused in 1 front limb, with the contralateral limb as control (60 mL 0.9% NaCl). A hole was drilled in the lateral cortex of P1, and blood samples from the medullary sinusoids of P1 were collected before infusion,...
Li Y, Yao J, Chang M, Nikolic D, Yu L, Yager JD, Mesecar AD, van Breemen RB, Bolton JL.Catechol-O-methyltransferase (COMT) plays an important role in the inactivation of biologically active and toxic catechols. It has been shown that COMT is genetically polymorphic with a wild-type and variant form where a valine has been substituted with a methionine. Several, but not all, epidemiological studies have shown that women, homozygous with the variant form, have an increased risk of developing breast cancer. Previously, we showed that 4-hydroxyequilenin (4-OHEN), a cytotoxic/genotoxic equine catechol estrogen metabolite, is both a substrate of COMT and an irreversible inhibitor of t...
Kannegieter NJ, Alley MR.A 20-month-old, Standard-bred colt was presented with an acute onset of hindlimb ataxia. Clinical and radiographic examination identified a compressive lesion affecting the spinal cord at the level of the 17th to 18th thoracic vertebrae. After euthanasia, post-mortem examination revealed a tumour in the epidural space, diagnosed histologically as a lymphosarcoma. Neoplastic lymphoid cells were also present in the abdominal lymph nodes and brain. Because of the disseminated nature of lymphosarcoma in the horse, involvement of the central nervous system is likely to be more common than is presen...
