Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Mehdizadeh Gohari I, Kropinski AM, Weese SJ, Whitehead AE, Parreira VR, Boerlin P, Prescott JF.Clostridium perfringens is an important cause of foal necrotizing enteritis and canine acute hemorrhagic diarrhea. A major virulence determinant of the strains associated with these diseases appears to be a beta-sheet pore-forming toxin, NetF, encoded within a pathogenicity locus (NetF locus) on a large tcp-conjugative plasmid. Strains producing NetF also produce the putative toxin NetE, encoded within the same pathogenicity locus, as well as CPE enterotoxin and CPB2 on a second plasmid, and sometimes the putative toxin NetG within a pathogenicity locus (NetG locus) on another separate large c...
Heffron B, Bash J, Larsen AK.The use of alkinizing agents by trainers to counteract the accumulation of lactic acid in racehorses has been well documented. A by-product of this administration is elevated total carbon dioxide (tCO2) concentrations. Most regulatory authorities have set the threshold for tCO2 in plasma at 37 mM. The quantification of tCO2 often presents a challenge to laboratories due to the instrumentation required, which can be expensive to use and maintain. The Beckman DxC 600 (Brea, CA) is currently used in our laboratory for tCO2 quantification. The goal of this research was to determine if another anal...
Rocha T.Contagious equine metritis (CEM), a highly contagious bacterial venereal infection of equids, caused by Taylorella equigenitalis, is of major international concern, causing short-term infertility in mares. Portugal has a long tradition of horse breeding and exportation and until recently was considered CEM-free. However, in 2008, T. equigenitalis was isolated at our laboratory from a recently imported stallion and 2 mares from the same stud. Following this first reported outbreak, the Portuguese Veterinary Authority (DGVA) performed mandatory testing on all remaining equines at the stud (n=30)...
Senju N, Tozaki T, Kakoi H, Shinjo A, Matsuyama R, Almunia J, Takasu M.Thirty-two microsatellites and a mitochondrial DNA haplotypes of endangered Yonaguni horses were analyzed to establish a pedigree registration system and to understand their genetic diversity for planning effective conservation. Blood samples were collected from 78 of the 130 horses in existence, and DNA was extracted and genotyped. There were two major findings. One is that it is possible to use microsatellites for Yonaguni horse pedigree registration in the future because the power of exclusion of parentage testing is reliable at 0.999998. The second is the clarification of the current genet...
Rodrigues VDS, Garcia MV, Cruz BC, Maciel WG, Zimmermann NP, Koller WW, Barros JC, Andreotti R.The objective of this study was to evaluate the life cycle and parasitic competence of Dermacentor nitens (Neumann, 1897) on different animal species. Experimental infestations were induced in five specimens each of seven species of possible hosts: rabbits, horses, sheep, cows, guinea pigs, birds and dogs. Rabbits were infested in the ear using artificial feeding chambers, and the horses, sheep, cows and dogs were infested in the ear without feeding chambers. For the infestation of guinea pigs, artificial feeding chambers were fixed on the back. Birds were infested by placing larvae on the bac...
Daneshvar Amoli A, Mohebali N, Farzaneh P, Shahzadeh Fazeli SA, Nikfarjam L, Ashouri Movasagh S, Moradmand Z, Ganjibakhsh M, Nasimian A, Izadpanah M....Caspian horse, a rare horse breed found in 1965 by Louise Firouz in northern Iran, is a small horse which is reported to be in danger of extinction in its original homeland. There seems to be a great need to prevent extinction of this valuable horse. In this study, 51 fibroblast cell lines from Caspian horse ear marginal tissue were successfully established by sampling 60 horses using primary explant technique. Cells were authenticated and growth curve was plotted. According to results obtained, population doubling time (PDT) was calculated 23 ± 0.5 h for all cell lines. Multiplex polymera...
Fielding CL, Meier CA, Fellers GK, Magdesian KG.OBJECTIVE To compare results of point-of-care laboratory testing with standard veterinary clinical examination findings at a single time point during endurance competition to identify horses at risk for elimination. ANIMALS 101 endurance horses participating in the 2013 Western States 160-km (100-mile) endurance ride. PROCEDURES At the 58-km checkpoint, blood samples were collected from all horses. Samples were analyzed for pH, Pco2, base excess, anion gap, PCV, and whole blood concentrations of sodium, potassium, chloride, total carbon dioxide, BUN, glucose, and bicarbonate. Corrected electro...
Serpa PB, Garbade P, Natalini CC, Pires AR, Tisotti TM.OBJECTIVE To develop a high-resolution melting (HRM) assay to detect the g.66493737C>T polymorphism in the myostatin gene (MSTN) and determine the frequency of 3 previously defined g.66493737 genotypes (T/T, T/C, and C/C) in warmblood horses. SAMPLES Blood samples from 23 horses. PROCEDURES From each blood sample, DNA was extracted and analyzed by standard PCR methods and an HRM assay to determine the MSTN genotype. Three protocols (standard protocol, protocol in which a high-salt solution was added to the reaction mixture before the first melting cycle, and protocol in which an unlabeled p...
Almeida JC, Vidotto O, Ferreira EP, Ribeiro LP, Mongruel AC, Vieira TS, Freire RL, Mota RA, Vieira RF.Although the infection by Toxoplasma gondii in horses is usually asymptomatic, it may be characterized by the presence of tissue cysts and maintenance of detectable antibody titers. The aim of this study was to detect anti-T.gondii antibodies and to determine risk factors associated in sport horses from Paraíba State, Northeastern Brazil. A total of 138 apparently healthy sport horses of different age and gender were sampled. Anti-Toxoplasma gondii antibodies were detected in 16/138 (11.6%; 95% CI: 6.77-18.14%) horses by indirect immunofluorescence antibody assay (IFA). A significant associat...
Lang A, Brucker P, Ludwig M, Wrede T, Theunert J, Gasse H.The topographical correlations between certain extracranial and intracranial osseous points of interest (POIs), and their age-related changes, are indispensable to know for a diagnostical or surgical access to intracranial structures; however, they are difficult to assess with conventional devices. In this pilot study, the 3-dimensional coordinates of extra-/intracranial POIs were determined, thus avoiding perspective distortions that used to be intrinsic problems in 2-dimensional morphometry. The data sets were then analysed by creating virtual triangles. The sizes, shapes, and positions of t...
Henry TJ, Puchalski SM, Arzi B, Kass PH, Verstraete FJM.There are several reports of incisor tooth resorption and hypercementosis in horses but, to date, studies have been limited in case numbers and to advanced lesions. Tooth resorption in other species is a radiographic diagnosis of types of resorption that are often identified before clinical signs. Our goal was to evaluate radiographically incisor tooth resorption in a large population of horses, utilising interpretation criteria from canine and human dentistry. Objective: To document and classify incisor tooth resorption and hypercementosis. Methods: Retrospective descriptive case series. Meth...
Olivo G, Lucas TM, Borges AS, Silva RO, Lobato FC, Siqueira AK, da Silva Leite D, Brandão PE, Gregori F, de Oliveira-Filho JP, Takai S, Ribeiro MG.Diarrhea is a major clinical problem affecting foals up to 3 months of age. The aim of this study was to identify enteric microorganisms involved in monoinfections and coinfections and the associated virulence factors in healthy and diarrheic foals. Diarrheic (D) ( = 56) and nondiarrheic (ND) foals ( = 60) up to three months of age were studied. Fecal samples were analyzed for identification of infectious agents (microbiological culturing, molecular techniques, and microscopic analyses). (30% versus 25%), spp. (25% versus 7%), (25% versus 25%), type A (21% versus 10%), (20% versus 35%), ...
Mizen K, Woodman J, Boysen SR, Wagg C, Greco-Otto P, Léguillette R, Roy MF.Blood lactate concentration is a marker of tissue perfusion and helps guide therapeutic interventions in critically ill horses. In both humans and dogs, administration of corticosteroids can increase blood lactate concentration, leading to type B hyperlactatemia. This effect could be a consequence of the impact of corticosteroids on glucose metabolism. Objective: To investigate the effects of daily IM dexamethasone administration on blood lactate and glucose concentrations in horses. Methods: Nine healthy adult horses. Methods: A randomized, blinded, controlled, cross-over study design was use...
Nürnberger S, Rentenberger C, Thiel K, Schädl B, Grunwald I, Ponomarev I, Marlovits S, Meyer C, Barnewitz D.The present study reports for the first time the presence of giant crystals in mitochondria of equine chondrocytes. These structures show dark contrast in TEM images as well as a granular substructure of regularly aligned 1-2 nm small units. Different zone axes of the crystalline structure were analysed by means of Fourier transformation of lattice-resolution TEM images proving the crystalline nature of the structure. Elemental analysis reveals a high content of nitrogen referring to protein. The outer shape of the crystals is geometrical with an up to hexagonal profile in cross sections. It ...
Muellner P, Muellner U, Gates MC, Pearce T, Ahlstrom C, O'Neill D, Brodbelt D, Cave NJ.Veterinary practitioners have extensive knowledge of animal health from their day-to-day observations of clinical patients. There have been several recent initiatives to capture these data from electronic medical records for use in national surveillance systems and clinical research. In response, an approach to surveillance has been evolving that leverages existing computerized veterinary practice management systems to capture animal health data recorded by veterinarians. Work in the United Kingdom within the VetCompass program utilizes routinely recorded clinical data with the addition of fur...
Gorissen BMC, Wolschrijn CF, Serra Bragança FM, Geerts AAJ, Leenders WOJL, Back W, van Weeren PR.Foals stand and walk immediately after birth, but insight into the subsequent longitudinal development of their gait kinetics in the early juvenile phase and the possible influence of osteochondrosis thereon is lacking. Objective: To quantify gait kinetics in foals during the first half year of life, taking into account their osteochondrosis status. Methods: Prospective, cohort study performed at a single stud farm. Methods: Pressure plate measurements at walk and trot from 11 Dutch Warmblood foals during the first 24 weeks of life were used to determine body mass normalised peak vertical forc...
Sadaba SA, Madariaga GJ, Botto CM, Carino MH, Zappa ME, García PP, Olguín SA, Massone A, Díaz S.Evidence of cerebellar abiotrophy (CA) was found in a six-month-old Arabian filly with signs of incoordination, head tremor, wobbling, loss of balance and falling over, consistent with a cerebellar lesion. Normal hematology profile blood test and cerebrospinal fluid analysis excluded infectious encephalitis, and serological testing for Sarcocystis neurona was negative. The filly was euthanized. Postmortem X-ray radiography of the cervical cephalic region identified not abnormalities, discounting spinal trauma. The histopathological analysis of serial transverse cerebellar sections by electron ...
Ayala-Valdovinos MA, Galindo-García J, Sánchez-Chiprés D, Duifhuis-Rivera T.Hydrocephalus in Friesian horses is an autosomal recessive hereditary disease that can result in an abortion, a stillbirth, or euthanization of a newborn foal. Here, the hydrocephalus-associated c.1423C > T mutation in B3GALNT2 gene was detected with PCR-RFLP and PCR-PIRA methods for horse genotyping. A preliminary genotyping survey was performed on 83 randomly selected Friesian stallion horses to determine the current allele frequency in Mexico. The frequency of the mutant T allele was 9.6%.
Djernaes JD, Nielsen JV, Berg LC.The widths of spaces between the thoracolumbar processi spinosi (interspinous spaces) are frequently assessed using radiography in sports horses; however effects of varying X-ray beam angles and geometric distortion have not been previously described. The aim of this prospective, observational study was to determine whether X-ray beam angle has an effect on apparent widths of interspinous spaces. Thoracolumbar spine specimens were collected from six equine cadavers and left-right lateral radiographs and sagittal and dorsal reconstructed computed tomographic (CT) images were acquired. Sequentia...
Haneda S, Nagaoka K, Nambo Y, Kikuchi M, Nakano Y, Li J, Matsui M, Miyake YI, Imakawa K.From previous cDNA subtraction studies analyzing gene expression in equine endometrium, high lipocalin 2 (LCN2) mRNA expression was found in the gravid endometrium. In the uterus, LCN2 may transport hydrophobic molecules and siderophores with iron, or may form a complex with another protein, however, the expression of uterine LCN2 beyond day 20 of equine pregnancy and its receptor has not been characterized. To study the expression and potential roles of uterine LCN2 from pre-implantation to mid-gestation period, stage-specific endometrial samples were obtained from day 13 (day 0 = ovulation) ...
Balasuriya UB, Lee PA, Tsai YL, Tsai CF, Shen YH, Chang HG, Skillman A, Wang HT, Pronost S, Zhang Y.Equine herpesvirus myeloencephalopathy (EHM), a major problem for the equine industry in the United States, is caused by equine herpesvirus-1 (EHV-1). In addition, EHV-1 is associated with upper respiratory disease, abortion, and chorioretinal lesions in horses. Here we describe the development and evaluation of an inexpensive, user-friendly insulated isothermal PCR (iiPCR) method targeting open reading 30 (ORF30) to detect both neuropathogenic and non-neuropathogenic strains on the field-deployable POCKIT™ device for point-of-need detection of EHV-1. The analytical sensitivity of the EHV-1 ...
Walter S, Rasche A, Moreira-Soto A, Pfaender S, Bletsa M, Corman VM, Aguilar-Setien A, García-Lacy F, Hans A, Todt D, Schuler G....The hepatitis C virus (HCV) is a major human pathogen. Genetically related viruses in animals suggest a zoonotic origin of HCV. The closest relative of HCV is found in horses (termed equine hepacivirus [EqHV]). However, low EqHV genetic diversity implies relatively recent acquisition of EqHV by horses, making a derivation of HCV from EqHV unlikely. To unravel the EqHV evolutionary history within equid sister species, we analyzed 829 donkeys and 53 mules sampled in nine European, Asian, African, and American countries by molecular and serologic tools for EqHV infection. Antibodies were found in...
Tozaki T, Kikuchi M, Kakoi H, Hirota KI, Mukai K, Aida H, Nakamura S, Nagata SI.Transcriptome analyses based on DNA microarray technology have been used to investigate gene expression profiles in horses. In this study, we aimed to identify exercise-induced changes in the expression profiles of genes in the peripheral blood of Thoroughbred horses using DNA microarray technology (15,429 genes on 43,603 probes). Blood samples from the jugular vein were collected from six horses before and 1 min, 4 hr, and 24 hr after all-out running on a treadmill. After the normalization of microarray data, a total of 26,830 probes were clustered into four groups and 11 subgroups showing si...
Scott SD, Kinsley R, Temperton N, Daly JM.Pseudotyped viruses (PVs) produced by co-transfecting cells with plasmids expressing lentiviral core proteins and viral envelope proteins are potentially powerful tools for studying various aspects of equine influenza virus (EIV) biology. The aim of this study was to optimise production of equine influenza PVs. Co-transfection of the HAT protease to activate the haemagglutinin (HA) yielded a higher titre PV than TMPRSS2 with the HA from A/equine/Richmond/1/2007 (H3N8), whereas for A/equine/Newmarket/79 (H3N8), both proteases resulted in equivalent titres. TMPRSS4 was ineffective with the HA of...
McGivney CL, Sweeney J, David F, O'Leary JM, Hill EW, Katz LM.Previous studies support good intra- and interobserver agreements for endoscopic evaluation of various upper respiratory tract (URT) diseases in horses. However, these studies mainly assessed resting endoscopic examination videos and/or focussed on a single URT abnormality. Objective: To estimate intra- and interobserver agreement for identification and grading of all URT abnormalities from resting and overground endoscopy (OGE) videos of Thoroughbreds. Methods: Blinded, fully crossed design. Methods: Resting and OGE URT videos for n = 43 Thoroughbreds were retrospectively chosen based on iden...
Yamaoka TT, Flaherty D, Pawson P, Scott M, Auckburally A.To assess agreement between noninvasive blood pressure (NIBP) oscillometrically-derived values from a multiparameter monitor (Datex Ohmeda S/5 Compact) with those obtained by invasive blood pressure (IBP) measurement in anaesthetised horses undergoing elective surgery. Methods: Prospective clinical study. Methods: A total of 40 healthy adult horses. Methods: Horses were anaesthetised with various anaesthetic protocols (based on clinical requirements). Depending on positioning, cannulation of the facial or lateral metatarsal artery was performed for IBP measurement. The cannula was connected vi...
Perrett J, Harris IT, Maddock C, Farnworth M, Pyatt AZ, Sumner RN.Over the past five decades, there has been increasing evidence to indicate global declines in human semen quality. Parallel adverse trends measured in male animals indicate a potential environmental aetiology. This study evaluated the progressive motility (PM) of stallion ejaculate through a systematic review and meta-analysis. A total of 696 estimates of equine PM from 280 studies, which collected semen samples between the years 1990 and 2018, were collated for meta-analysis. The method of motility analysis, breed, season of collection, and geographical location were extracted. Simple linear ...
Davidson EJ.Controlled exercise is a fundamental and critical component of any rehabilitation program for the equine athlete. The ideal controlled exercise program is designed to complement the normal tissue reparative process after injury. As a general rule, the program starts with complete rest followed by stall rest and short periods of walking. Over time, the intensity of the controlled exercise is gradually and systemically increased until complete healing has occurred. A well-designed, injury-directed, controlled exercise program enhances the healing process.
Tung JT, Fenton JI, Arnold C, Alexander L, Yuzbasiyan-Gurkan V, Venta PJ, Peters TL, Orth MW, Richardson DW, Caron JP.Interleukin-1 is considered a central mediator of cartilage loss in osteoarthritis in several species, however an equine recombinant form of this cytokine is not readily available for in vitro use in equine osteoarthritis research. Equine recombinant interleukin-1beta was cloned and expressed and its effects on the expression and activity of selected chondrocytic proteins implicated in cartilage matrix degradation were characterized. Reverse transcriptase polymerase chain reaction methods were used to amplify the entire coding region of the equine IL-1beta mRNA, which was cloned into an expres...
Dauphin G, Legay V, Sailleau C, Smondack S, Hammoumi S, Zientara S.Borna disease virus (BDV) is an enveloped, non-segmented negative-stranded RNA virus which belongs to the Bornaviridae family. BDV is an aetiological agent of encephalitis in horses, sheep and several other vertebrate species. In order to extend our knowledge about the presence of BDV in France, a study based on BDV RNA detection by RT-nested-PCR was done with 196 animal tissues: 171 brain samples collected from different animal species (75 horses, 59 foxes, 31 cattle, 4 dogs, 1 sheep, 1 roe deer) and 25 horse blood samples. An RNA internal standard molecule was constructed and was co-amplifie...
de Waal DT, Potgieter FT.Rhipicephalus evertsi evertsi larvae were fed on the ears of rabbits. Seven days after larval infestation, unfed, newly moulted nymphae were manually removed to infest a splenectomized donkey showing a patent Babesia caballi infection. Engorged nymphae were collected from the donkey and the ensuing adult ticks were placed on a susceptible horse. The horse contracted a B. caballi infection showing a prepatent period of 19 days after tick infestation. A very low parasitaemia, (highest score 2), which was patent for only 10 days, was recorded. The lowest packed cell volume recorded was 16%.
Na W, Lyoo KS, Yoon SW, Yeom M, Kang B, Moon H, Kim HK, Jeong DG, Kim JK, Song D.Equine influenza virus (EIV) causes a highly contagious disease in horses and other equids. Recently, we isolated an H3N8 EIV (A/equine/Kyonggi/SA1/2011) from a domestic horse in South Korea that exhibited symptoms of respiratory disease, and found that the EIV strain contained a naturally mutated NS gene segment encoding a truncated NS1 protein. In order to determine whether there was an association between the NS gene truncation and viral virulence, a reverse genetics system was applied to generate various NS gene recombinant viruses using the backbone of the H1N1 A/Puerto Rico/8/1934 (PR/8)...
Tozaki T, Hirota K, Hasegawa T, Tomita M, Kurosawa M.Linkage disequilibrium (LD) mapping is often used in searches for genes governing economically significant traits and diseases. The D' coefficient is a commonly used measure of the extent of LD between all possible pairs of alleles at two markers. This study aimed to test the utility of the D' coefficient for LD mapping of a trait in a thoroughbred population. Microsatellite genotype data and grey coat colour as a trait model in a thoroughbred population were used to assess the extent of LD. We demonstrated that LD mapping was a reasonable approach for initial genome-wide scans in a thoroughbr...
Sarkar S, Balasuriya UB, Horohov DW, Chambers TM.Equine herpesvirus-1 (EHV-1) infects equine endothelial cells (EECs) lining the small blood vessels in the central nervous system. However, the effect of type I IFN on EHV-1 replication in the EECs is not well studied. Thus, the primary objective of this study was to investigate the effect of type-I IFN on the replication of the neuropathogenic T953 strain of EHV-1 in vitro in EECs. The initial data showed that the EHV-1 was partly resistant to the biological effect of exogenously supplied recombinant equine IFN-α. Subsequent investigation into the mechanism of resistance showed that EHV-1 in...
Ricord M, Andrews FM, Yñiguez FJM, Keowen M, Garza F, Paul L, Chapman A, Banse HE.Phenylbutazone is commonly prescribed for treatment of various painful or inflammatory disorders in horses, but is associated with gastrointestinal (GI) adverse effects. Anecdotally, many practitioners prescribe omeprazole concurrently with phenylbutazone to reduce development of equine gastric ulcer syndrome (EGUS), but the efficacy and safety of this practice remains unknown. Objective: To evaluate the effect of omeprazole on phenylbutazone-induced equine glandular gastric disease (EGGD) and equine squamous gastric disease (ESGD). Methods: Randomised block experimental design. Methods: Twent...
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Kusano K, Nagata SI.Processed pseudogenes, also known as retrocopy genes, are copies of messenger RNAs that have been reverse transcribed into DNA and inserted into the genome. In this study, we identified 62 processed pseudogene candidates as intron-less genes from whole-genome sequencing (WGS) data of Thoroughbred horses using delly structural variation software. The 62 processed pseudogene candidates were confirmed by PCR amplification of intron-less products. A total of 11 processed pseudogenes were confirmed in the genome of all 23 analysed horses, whereas three processed pseudogenes with structures of ATP11...
Pashen RL, Sheldrick EL, Allen WR, Flint AP.The gonads of the fetal horse were found to be relatively devoid of 3 beta-hydroxysteroid dehydrogenase and other enzymes which metabolize dehydroepiandrosterone (DHA). In short-term in-vitro incubation experiments fetal liver converted DHA to the potential equilin precursor, 7 alpha-hydroxy DHA. DHA was converted to oestrone when incubated with extracts of horse placenta but 7 alpha-hydroxy DHA was not converted to equilin. Levels of DHA measured in peripheral blood of mares throughout pregnancy paralleled those of equilin and oestrone, and DHA concentrations fell rapidly after fetal gonadect...
De Zani D, Borgonovo S, Biggi M, Vignati S, Scandella M, Lazzaretti S, Modina S, Zani D.Clinical and radiographic investigations of paranasal sinuses in horses are difficult due to the complex anatomy of these regions, the lack of patognomonic symptoms, and the low sensitivity of conventional diagnostic techniques. The aim of this study was to produce an anatomical atlas to support computed tomography (CT) and sinuscopy of the paranasal sinuses of the adult horse. Transverse, sagittal, and dorsal CT images were acquired, and sinuscopy with both rigid and flexible endoscopes was performed. The heads were frozen and sectioned using a band saw, with the cuts aligned as close as poss...
Gerring EE, Hunt JM.An experimental model of postoperative ileus was developed in ponies using trauma to, and exposure of, a length of small intestine which gave rise to a reproducible and reversible set of changes in gut activity. This was assessed by recordings of electrical and mechanical activity and by propulsion of spheres from stomach to anus. Activity was depressed, especially in the stomach and colon, and transit was slowed. All drugs given increased electromechanical activity but propranolol was the least effective and did not alter the delayed transit of spheres. Yohimbine was more effective and the ad...
Sieme H, Schäfer T, Stout TA, Klug E, Waberski D.This study investigated the effects of different artificial insemination (AI) regimes on the pregnancy rate in mares inseminated with either cooled or frozen-thawed semen. In essence, the influence of three different factors on fertility was examined; namely the number of inseminations per oestrus, the time interval between inseminations within an oestrus, and the proximity of insemination to ovulation. In the first experiment, 401 warmblood mares were inseminated one to three times in an oestrus with either cooled (500 x 10(6) progressively motile spermatozoa, stored at +5 degrees C for 2-4 h...
Vieira TS, Vieira RF, Krawczak FS, Soares HS, Guimarães AM, Barros-Filho IR, Marcondes M, Labruna MB, Biondo AW, Vidotto O.Although well established in dogs, Ehrlichia sp. infection has been scarcely reported in horses. The aim was to perform a comprehensive serological and molecular survey for the detection of Ehrlichia spp. in carthorses from Southern Brazil. Blood samples from 190 carthorses from Paraná State were sampled. Horses were also tested for Borrelia burgdorferi and Anaplasma phagocytophilum. Anti-Ehrlichia sp. antibodies were detected by a commercial rapid ELISA, and immunofluorescence antibody assays (IFA) with E. chaffeensis and E. canis as crude antigens. The molecular and phylogenetic analysis of...
Keen JA, McGorum BC, Hillier C, Nally JE.This study investigated the effects of cortisol and insulin, hormones that affect both glycaemic status and vascular function, on the in vitro contractility of isolated healthy equine small laminar veins. Small veins (150-500 μm) draining the digital laminae from healthy horses or ponies were investigated by wire myography. Concentration response curves were constructed for noradrenaline (NA), phenylephrine (PE), endothelin-1 (ET-1) and 5-hydroxytryptamine (5-HT) in the presence of either cortisol (10(-6 ) m) or insulin (1000 μIU/mL). Cortisol significantly increased the maximum contractilit...
Brownlow MA, Brotherhood JR.Exertional heat illness (EHI) is a syndrome that occurs when metabolic heat production from muscular contraction exceeds the rate at which it can be dissipated. Core body temperature rises to critical levels, causing hyperthermia and central nervous system dysfunction. Best practice for the prevention of EHI centres around early detection, rapid response and aggressive cooling. Advance planning enables risk mitigation measures. The more that is known about EHI in horses, the better prepared those in the positions of responsibility can be to anticipate events in which the risk of EHI may be ele...
Weese JS, Sabino C.Antimicrobials had been administered to 38/55 (69%) racing standardbred and Thoroughbred horses with poor performance, subsequently diagnosed with nonseptic inflammatory airway disease. Horses with cough were more commonly treated (P = 0.02). In almost all cases, no clinical signs suggested that bacterial infection was present. Inappropriate use of antimicrobials was common. Des antimicrobiens ont été administrés à 38/55 (69 %) chevaux standardbreds et chevaux pursang affichant une piètre performance, diagnostiqués par la suite avec une maladie inflammatoire aseptique des voies respirat...
Plasenzotti R, Stoiber B, Posch M, Windberger U.Comparative animal studies showed the wide variation of whole blood and plasma viscosity, and erythrocyte aggregation among mammalian species. Whole blood viscosity and red blood cell aggregation is influenced by red cell fluidity. To evaluate differences in erythrocyte deformability in mammals, three species were investigated, whose erythrocytes have a different aggregation property: horse, as a species with high, dog with medium, and sheep with almost unmeasurable aggregation tendency. Erythrocyte deformability was tested ektacytometrically (Elongation Index [EI], LORCA, Mechatronics, Hoorn,...
Maitho TE, Lees P, Taylor JB.The disposition of phenylbutazone (4.4 mg/kg), administered intravenously to six Welsh Mountain ponies, was described by a two-compartment open model. Pharmacokinetic parameters were not significantly different after morning dosing in comparison with afternoon dosing. When phenylbutazone (4.4 mg/kg) was administered orally to the same ponies, marked variations in time to peak concentrations were produced with different feeding schedules. When access to hay was permitted before and after dosing, the mean time to peak concentration was 13.2 +/- 1.2 h and double peaks in the plasma concentration-...
Maher JK, Tresnan DB, Deacon S, Hannah L, Antczak DF.Down-regulation of major histocompatibility complex (MHC) genes by trophoblast cells is considered to be a primary mechanism preventing maternal immune rejection of the fetal-placental unit in mammalian pregnancy by rendering these cells, which form the primary barrier between mother and fetus, relatively non-antigenic. In situ hybridization with probes encoding human and horse MHC class I genes was used to characterize the pattern of MHC class I mRNA expression in the various forms of horse trophoblast. Strong hybridization signals were observed in the invasive trophoblast cells of chorionic ...
Rizk MA, El-Sayed SAE, Eltaysh R, Igarashi I.Equine piroplasmosis is a tick-transmitted disease that is considered one of the most serious infectious diseases affecting equines. Searching for novel antipiroplasm drugs remains indispensable due to the emergence and spreading of resistant piroplasm parasites against the limited currently used drugs, diminazene aceturate and imidocarb dipropionate. Therefore, novel drugs with specified targets need to be identified and exploited. The inhibitory effects of Medicines for Malaria Venture (MMV) Malaria Box compounds with potent in vitro anti-equine piroplasmosis activity were evaluated against ...
Brogan PT, Henning H, Stout TA, de Ruijter-Villani M.Colour-flow Doppler sonography has been described as a means of assessing corpus luteum (CL) function rapidly, because area of luteal blood vessels correlates well with circulating progesterone (P4) concentrations [P4] in oestrous cycling mares. The aim of this study was to assess the relationships between CL size and vascularity, and circulating [P4] during early pregnancy in mares, and to determine whether luteal blood flow was a useful aid for selecting an embryo transfer recipient. Equine embryos (n=48) were recovered 8 days after ovulation and were transferred to available recipient mares...
Lind EO, Christensson D.In the last few years stud farms have experienced increasing problems with Parascaris equorum infections in foals despite intensive deworming programs. This has led to the question as to whether the anthelmintic drugs used against this parasite are failing. This study aimed to investigate the efficacy of ivermectin, fenbendazole and pyrantel on the faecal output of ascarid eggs of foals. Methods: A Faecal Egg Count Reduction Test (FECRT) was performed on nine large studs in Sweden. Anthelmintic drugs were given orally and faecal samples were examined for ascarid eggs on the day of deworming an...
Szczerbal I, Nowacka-Woszuk J, Kopp-Kuhlman C, Mackowski M, Switonski M.X monosomy is the most common disorder of sex development in horses. Although cytogenetic analysis is still the gold standard in the diagnosis of equine X monosomy, novel molecular techniques are being sought to quickly and reliably detect this chromosome abnormality. Objective: The goal of this study was to evaluate the usefulness of a novel variant of the PCR technique-namely, droplet digital PCR (ddPCR)-in the detection of X monosomy in mares. Methods: A proof of concept of the usefulness of ddPCR in diagnosing an abnormal number of X chromosomes in mares. Methods: We examined an infertile ...
