"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.
Sleutjens J, Cooley AJ, Sampson SN, Wijnberg ID, Back W, van der Kolk JH, Swiderski CE.The impact of cervical pathology on performance is of great importance to the horse industry. Accurate diagnosis of cervical disease with imaging modalities, including computed tomography (CT) and magnetic resonance imaging (MRI), requires thorough appreciation of normal cervical anatomy. Objective: (1) To describe in detail the anatomy of the equine cervical spine by comparing anatomical sections with corresponding MR and contrast-enhanced CT images in the sagittal, dorsal, and transverse plane. (2) To discuss the ability of MR and contrast-enhanced CT imaging to visualize anatomical structur...
Tydén E, Dahlberg J, Karlberg O, Höglund J.The development of anthelmintic resistance (AR) to macrocyclic lactones in the equine roundworm Parascaris equorum has resulted in benzimidazoles now being the most widely used substance to control Parascaris infections. However, over-reliance on one drug class is a risk factor for the development of AR. Consequently, benzimidazole resistance is widespread in several veterinary parasites, where it is associated with single nucleotide polymorphisms (SNPs) in drug targets encoded by the β-tubulin genes. The importance of these SNPs varies between different parasitic nematodes, but it has been h...
Bonilla AG, Williams JM, Litsky AS, Santschi EM.To determine ex vivo contact data on the equine medial tibial plateau loaded by an intact medial femoral condyle (MFC), by an MFC with an osteochondral defect, and with a screw inserted in lag fashion through the MFC defect. Methods: Ex vivo experiment. Methods: Stifles (n = 6). Horses (n = 4). Methods: Stifle joints were axially loaded to 1800 N at 155°, 145°, and 130°, under 3 conditions: Intact, MFC with a 15 mm circular osteochondral defect, and with a transcondylar screw inserted in lag fashion through the defect. An electronic pressure sensor (Tekscan®) on the medial tibial plateau...
Nedjadi T, Moran AW, Al-Rammahi MA, Shirazi-Beechey SP.The diet of the horse, pasture forage (grass), is fermented by the equine colonic microbiota to short-chain fatty acids, notably acetate, propionate and butyrate. Short-chain fatty acids provide a major source of energy for the horse and contribute to many vital physiological processes. We aimed to determine both the mechanism of butyrate uptake across the luminal membrane of equine colon and the nature of the protein involved. To this end, we isolated equine colonic luminal membrane vesicles. The abundance and activity of cysteine-sensitive alkaline phosphatase and villin, intestinal luminal ...
Lashley MJ, Nauwelaerts S, Vernooij JC, Back W, Clayton HM.Among veterinary surgeons, interest has recently increased in the role of the horse's neck as a causative factor in complex locomotor disturbances. Specifically, controversy surrounds the trend for the head to be carried behind the vertical (BHV) in contravention of Fédération Equestre Internationale (FEI) rules. The aim of this study was to determine whether the head angulation of elite dressage horses has changed over the last 25 years, and whether head angulation correlates with the competition score awarded. Head angle was measured from videos recorded during the Grand Prix test at the 1...
Mosseri S, Hetzel U, Hahn S, Michaloupoulou E, Sallabank HC, Knottenbelt DC, Kipar A.Sarcoids are the most prevalent equine skin tumours and remain a therapeutic challenge due to their differing clinical morphology, local aggressive behaviour, and high recurrence following surgical treatment. In vitro, sarcoid derived fibroblasts are invasive and express matrix metalloproteinase (MMP) -1, -2 and -9. It was hypothesised that the MMPs produced by neoplastic cells play a role in both their local invasiveness and interaction with the overlying epidermis (picket fence formation). The objective of this morphological study was to investigate the local behaviour and in situ MMP expres...
Lyons ET, Tolliver SC, Kuzmina TA, Dzeverin II, Nielsen MK, McDowell KJ.The main purpose of the research was to determine if three weekly samplings would produce consistent results for low strongyle egg shedders, generally associated with older horses. Strongyle egg counts per gram of feces (EPG) were done for 661 Thoroughbred mares on 14 farms in 2012-2013 once a week for three consecutive weeks. None of the mares had been treated with ivermectin or moxidectin for more than 90 days and with fenbendazole, oxibendazole, or pyrantel pamoate for more than 60 days. Strongyle EPG count data indicated that 38.3% of the mares were positive at first and second sampling, a...
Annand EJ, Reid PA.The first two confirmed cases of Australian bat lyssavirus (ABLV) infection in horses are presented. Both cases occurred in the same week in May 2013 in paddock mates in south-east Queensland. Australia has been one of only a few countries considered free from rabies-like viruses in domestic animal species. ABLV infection had previously only been confirmed in bats and humans. All three confirmed human cases were fatal, the latest in February 2013. An additional human case of possible abortive infection in 1996 has also been reported. Both equine cases reported here resulted in euthanasia. The ...
Østevik L, Gunnes G, de Souza GA, Wien TN, Sørby R.Localized nasal, conjunctival and corneal amyloidosis was diagnosed in a 15-year-old pony with nasal and conjunctival masses and severe dyspnoea. Multiple swellings had been evident in the nostrils for at least two years and had gradually increased in size before presentation due to dyspnoea and exercise intolerance. Surgical debulking of the masses was performed and histological examination revealed large amounts of extracellular, hyaline, eosinophilic, Congo red positive material in the lamina propria of the nasal mucosa. A tentative diagnosis of localized nasal amyloidosis was made. The tre...
Hinnigan G, Milner P, Talbot A, Singer E.To investigate the specificity of anaesthesia of the deep branch of the lateral plantar nerve (DB-LPN). Methods: Twenty horses had DB-LPN anaesthesia performed by a single injection technique as part of a lameness investigation. The mechanical nociceptive threshold (NT) was measured using a handheld force meter at six points on the lateral aspect of the limb: before diagnostic anaesthesia (T0), and at 15 (T15) and 30 (T30) minutes post anaesthesia. Paired t-tests were performed and significance was set at p <0.05. In addition, ten cadaveric limbs were injected with 2.5 ml new methylene blue...
Schneider CP, Ishihara A, Adams TP, Zekas LJ, Oglesbee M, Bertone AL.To determine analgesic effects of intraneural injection of ethyl alcohol or formaldehyde in the palmar digital nerves of horses. Methods: 6 horses. Methods: Ethyl alcohol was injected in the medial palmar digital nerve of 1 forelimb, and formaldehyde was injected in the contralateral nerve. The lateral palmar digital nerve in 1 forelimb was surgically exposed, but not injected, and the contralateral lateral palmar digital nerve was not treated. For each heel, severity of lameness in response to experimentally induced heel pain (lameness score and peak vertical force), thermal reaction time, an...
Rebordão MR, Carneiro C, Alexandre-Pires G, Brito P, Pereira C, Nunes T, Galvão A, Leitão A, Vilela C, Ferreira-Dias G.Besides the classical functions, neutrophils (PMNs) are able to release DNA in response to infectious stimuli, forming neutrophil extracellular traps (NETs) and killing pathogens. The pathogenesis of endometritis in the mare is not completely understood. The aim was to evaluate the in vitro capacity of equine PMNs to secrete NETs by chemical activation, or stimulated with Streptococcus equi subspecies zooepidemicus (Szoo), Escherichia coli (Ecoli) or Staphylococcus capitis (Scap) strains obtained from mares with endometritis. Ex vivo endometrial mucus from mares with bacterial endometritis wer...
Yin X, Guo M, Gu Q, Wu X, Wei P, Wang X.Tetherin is an interferon-inducible host cell factor that blocks the viral particle release of the enveloped viruses. Most knowledge regarding the interaction between tetherin and viruses has been obtained using the primate lentiviral system. However, much less is known about the functional roles of tetherin on other lentiviruses. Equine infectious anemia virus (EIAV) is an important macrophage-tropic lentivirus that has been widely used as a practical model for investigating the evolution of the host-virus relationship. The host range of EIAV is reported to include all members of the Equidae ...
Patan-Zugaj B, Gauff FC, Plendl J, Licka TF.To investigate effects of endotoxin on leukocyte activation and infiltration of the laminar tissue in isolated perfused equine limbs. Methods: 10 right forelimbs and 3 left forelimbs collected from 10 healthy adult horses after slaughter at a licensed abattoir. procedures: Isolated right forelimbs were randomly assigned to 2 groups (5 forelimbs/group): perfusion of the distal portion for 10 hours with 80 ng of endotoxin/L and perfusion under the same conditions without endotoxin. After perfusion, samples for immunohistochemical detection of leukocytes (by use of antibodies against calprotectin...
Moorman VJ, Reiser RF, Mahaffey CA, Peterson ML, McIlwraith CW, Kawcak CE.To determine intralimb orientation changes with an inertial measurement unit (IMU) in hooves of horses at a walk and trot after induction of weight-bearing single forelimb lameness and to determine whether hoof orientations are similar to baseline values following perineural anesthesia. Methods: 6 clinically normal horses. Methods: 3-D hoof orientations were determined with an IMU mounted on the right forelimb hoof during baseline conditions, during 3 grades of lameness (induced by application of pressure to the sole), and after perineural anesthesia. Linear acceleration profiles were used to ...
Palmer DG, Lyon J, Palmer MA, Forshaw D.To determine the specificity and sensitivity of a commercial copro-antigen ELISA for the detection of Fasciola hepatica infection in cattle and sheep and to assess the suitability of the test for use in horses. Methods: Testing was done on more than 100 negative faecal samples from each of sheep, cattle and horses and on at least 40 positive faecal samples from each species. Positive samples were selected based on a positive sedimentation test for liver fluke eggs. Faecal samples of animals from Western Australia, which is free of liver fluke infection, served as negative controls. Specificity...
Petersen JL, Valberg SJ, Mickelson JR, McCue ME.Two variants in the equine myostatin gene (MSTN), including a T/C SNP in the first intron and a 227-bp SINE insertion in the promoter, are associated with muscle fiber type proportions in the Quarter Horse (QH) and with the prediction of race distance propensity in the Thoroughbred (TB). Genotypes from these loci, along with 18 additional variants surrounding MSTN, were examined in 301 horses of 14 breeds to evaluate haplotype relationships and diversity. The C allele of intron 1 was found in 12 of 14 breeds at a frequency of 0.27; the SINE was observed in five breeds, but common in only the T...
Mesenchymal stem cells (MSCs) offer promise as therapeutic aids in the repair of tendon and ligament disorders in sport horses. Equine allogeneic MSCs derived from umbilical cord blood (eUCB-MSCs) can be obtained in a minimally invasive fashion with successful propagation of MSCs. Objective: The objective of this study was to determine the applicability and therapeutic effect of eUCB-MSCs on tendinitis of the superficial digital flexor tendon, desmitis of the suspensory ligament, tendinitis of the deep digital flexor tendon, and desmitis of the inferior check ligament in clinical cases. Method...
Lee H, Kirkland WG, Whitmore RN, Theis KM, Young HE, Richardson AJ, Jackson RL, Hanson RR.Thicknesses of fresh equine articular cartilage surfaces from the fetlock, carpal and stifle joints were measured employing a needle probe test. Methods: Eighty-seven samples used in measurement were cultivated from fetlock, carpal and stifle joints of 12 deceased within 4 h of death. After approximately three minutes of exposure to air during dissection, all cartilage samples were preserved in a saline solution to keep the articular cartilage hydrated for testing. The thickness was measured on five different spots on the same sample. The thicknesses of the fetlock, carpus and stifle were co...
Villalba M, Santiago I, Gómez de Segura IA.The aim of this investigation was to determine the isoflurane-sparing effect and impact on arterial blood pressure and anaesthetic recovery of a constant rate infusion of medetomidine-propofol in horses. In a prospective, crossover, randomised study, six healthy horses (mean ± SD age, 13.7 ± 7.7 years; weight, 433 ± 51 kg) were anaesthetised twice with isoflurane and were randomly assigned to receive one of two treatments on each occasion, at least 2 weeks apart. The first treatment was saline (CTL group) and the second a medetomidine-propofol infusion (MP group; 1.25 µg/kg...
Aguilar JJ, Cuervo-Arango J, Santa Juliana L.It is scientifically demonstrated that lunar cycles have important effects on several biological events. Controversy exists about the lunar influence on human and animal parturition. In addition, in the horse industry, especially in Polo Horse breeders of Argentina and around the world there is a higher demand for female offspring than for males. The objective of this study was to determine whether there is a significant association between the lunar phase at the time of mating and the sex ratio at birth in horses. The Argentinean Stud Book provided information related to all matings registere...
Lyons ET, Tolliver SC.The prevalence of patent Strongyloides westeri infections was determined by examination for eggs in fecal samples collected from 513 Thoroughbred (TB) foals between February 25 and June 3, 2014. The study was conducted with 244 colts and 269 fillies from 11 well-managed farms in Central Kentucky. Foals ranged from 17 to 117 days of age and had never been dewormed. The mean prevalence of patent S. westeri infection was 30% (156/513 foals). This prevalence was substantially greater than historical reports from the same sampling area during the late 1990s and early 2000s. It is hypothesized that ...
Sykes BW, Sykes KM, Hallowell GD.Interest in Equine Gastric Ulcer Syndrome (EGUS) has recently increased in part due to a growing awareness of the differences between squamous and glandular disease. The pathophysiology and epidemiology of squamous and glandular disease are different and recently it has been shown that the response of glandular gastric ulceration to monotherapy with omeprazole is poor. Given these differences it has been recommended that specific treatment guidelines be formulated for equine glandular disease and that adjunctive therapies be investigated. Along these lines it has been suggested that the additi...
Dong J, Cook FR, Haga T, Horii Y, Norimine J, Misawa N, Goto Y, Zhu W.Although equine infectious anemia virus (EIAV) poses a major threat to the equine industry worldwide, the molecular epidemiology of this virus is poorly understood. Recently, an EIAV strain (EIAVMiyazaki2011-A) representing a new monophyletic group was discovered in feral horses in southern Japan. In the present study, the EIAVMiyazaki2011-A proviral genome is compared with evolutionarily divergent EIAV isolates to investigate conservation of functional elements or motifs within the long terminal repeats (LTRs) and structural genes. This analysis represents a significant step forward in increa...
Bergström K, Grönlund U.Detection of nosocomial methicillin-resistant Staphylococcus aureus infections in horses in Sweden has increased attention on infection control (IC) in equine hospitals. This study established baseline data on IC programmes within such settings, evaluated compliance with some IC procedures before and after an education intervention, and examined barriers to compliance.The study was carried out between 2008 and 2011 in four Swedish equine hospitals. Data on current IC of each hospital, purchase data on hand sanitisers and disposable gloves per patient, and direct observations of compliance with...
Dubuc J, Lavoie JP.The objective of this study was to determine whether eosinophils infiltrate the airway wall of horses with heaves. Eosinophils were evaluated using paraffin embedded lung tissues from six heaves-affected horses in crisis and six aged-matched controls. Slides were stained using Luna's method and eosinophils enumerated using histomorphometric techniques. Total eosinophil counts (expressed per mm(2) of basement membrane) were significantly higher in the airways of controls horses than in horses with heaves. Intraluminal, intraepithelial, and airway smooth muscle eosinophils counts were also incre...
Soma LR, Uboh CE, Guan F, McDonnell S, Pack J.Anabolic steroids (ABS) boldenone (BL; 1.1 mg/kg) and stanozolol (ST; 0.55 mg/kg) were administered i.m. to horses and the plasma samples collected up to 64 days. Anabolic steroids and androgenic steroids (ANS) in plasma were quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The limit of detection of all analytes was 25 pg/mL. The median absorption (t1/2 partial differential) and elimination (t1/2e) half-lives for BL were 8.5 h and 123.0 h, respectively, and the area under the plasma concentration-time curve (AUCho) was 274.8 ng.h/mL. The median t1/2e for ST was 82.1 ...
Wassmuth AK, Riond B, Hofmann-Lehmann R, Lutz H.The Mythic 18 is a fully automated hematology bench-top analyzer using impedance technology for a complete blood cell count (CBC) and a 3-part white blood cell count (WBC) differential. The purpose of the current study was to evaluate the Mythic for assessment of agreement, precision, linearity, carry-over, stability, and usability under practice conditions. Ethylenediamine tetra-acetic acid-blood samples from 122 dogs, 140 cats, and 123 horses were analyzed with the Mythic and reference methods (Sysmex XT-2000iV, manual hematocrit, and microscopic WBC differentiation). Pearson's coefficient o...
Oliveira T, Santos A, Silva J, Trindade P, Yamada A, Jaramillo F, Silva L, Baccarin R.In humans, hospitalisation, disease type, and environmental factors evidently affect the quality of sleep, further influencing patient recovery. The objective of the present study was to report the resting and lying behaviour of hospitalised horses, and whether lying behaviours differ depending on the physiological severity of joint damage. We hypothesised that the resting and lying behaviour can change during the hospitalisation and physiological severity of joint damage affect the time of rest in horses. A descriptive observational study was performed to evaluate the effect of hospitalisatio...
Nollet H, Van Ham L, Gasthuys F, Dewulf J, Vanderstraeten G, Deprez P.Horses need to be sedated before they are investigated by transcranial magnetic stimulation because of the mild discomfort induced by the evoked muscle contraction and the noise of stimulation. This paper describes the influence of a combination of detomidine (10 microg/kg bodyweight) and a low dose of buprenorphine (2.4 microg/kg) on the onset latency and peak-to-peak amplitude of magnetic motor-evoked potentials in normal horses. There were no significant differences between measurements of these parameters made before the horses were sedated and measurements made 10 and 30 minutes after the...
Bedenice D, Heuwieser W, Brawer R, Solano M, Rand W, Paradis MR.A total of 207 thoracic radiographs obtained from 128 foals were evaluated to assess the impact of pulmonary radiographic pattern, distribution, and severity of pulmonary changes on short-term survival of neonatal foals. The association between selected clinical variables and the radiographic manifestation of neonatal respiratory disease was also investigated. The evaluation of interstitial and alveolar-interstitial radiographic patterns within the caudodorsal, caudoventral, and cranioventral lung regions proved to be highly reliable between viewers in the study. A diagnosis of systemic inflam...
Calisher CH, Oro JG, Lord RD, Sabattini MS, Karabatsos N.A virus isolated from the blood of a febrile horse in Argentina was identified as a strain of Kairi virus. This is the fifth Bunyamwera serogroup virus isolated from livestock and wild animals in the Americas. Bunyamwera serogroup viruses have been isolated from febrile humans in the Americas and Africa.
Stier R, Tavassol F, Dupke C, Rüter M, Jehn P, Gellrich NC, Spalthoff S.The purpose of this study was to estimate the effect of the mechanism of trauma (fall versus kick), rider demographics, equestrian experience, protective equipment, and whether or not a horse was shod on the anatomic site of a horse-related maxillofacial fracture, operating time, postoperative complication rate, and length of hospital stay. Methods: We retrospectively reviewed the medical records of patients treated for horse-related maxillofacial fractures at a single institution in Germany between January 2000 and March 2015. We used linear and logistic regression to test the above-mentioned...
Brooks MB.The most common cause of hemorrhage is vascular injury; however, the possibility of hemostatic failure should be considered in the initial differential diagnosis. This article provides an overview of preliminary screening and definitive tests to identify hemostatic defects in horses.
van der Kolk JH, Heinrichs M, van Amerongen JD, Stooker RC, in de Wal LJ, van den Ingh TS.To determine size and weight of the pituitary gland and associations between pituitary gland size and weight and sex and age in horses without clinical signs associated with pituitary pars intermedia adenoma (PPIA) and horses and ponies with PPIA. Methods: Pituitary glands from 100 horses without clinical signs of PPIA and 19 horses and 17 ponies with PPIA. Methods: Pituitary glands were weighed, measured, and examined histologically by use of H&E stain. Masson trichrome and periodic acid-Schiff staining were used, when appropriate. Histologic lesions in the pars intermedia, pars distalis,...
Mignot CC, Pirottin D, Farnir F, de Moffarts B, Molitor C, Lekeux P, Art T.The effects of strenuous exercise and ex vivo stimulation of TLR3 and TLR4 pathways on the expression of six inflammatory genes in equine pulmonary leukocytes were investigated. The genes tested were interferon-beta (IFN-β), interleukin-1-beta (IL-1β), interleukin-6 (IL-6), interferon gamma-induced protein 10 (IP-10), chemokine (c-c motif) ligand 5 (RANTES) and tumor necrosis factor-alpha (TNF-α). We hypothesized that strenuous exercise would modulate basal gene expression on one hand and modulate the response to bacterial lipopolysaccharide (LPS) and to polyinosinic:polycytidylic acid (Pol...
Costa SCL, de Souza Freitas J, Carvalho FS, Pereira MJS, Cordeiro MD, da Fonseca AH, Gomes Jusi MM, Machado RZ, Munhoz AD.Currently, various zoonotic diseases are classified as emerging or reemerging. Because equids have a direct relationship with various vectors, they are possibly more frequently exposed to zoonotic agents than are humans. The undeniable importance of diseases such as human granulocytic anaplasmosis, spotted fever, and leishmaniasis for both public and animal health, as well as the possibility of equids acting as sources, reservoirs, or even sentinels for these pathogens, justifies the detection of their frequency and factors associated with infection in equids from northeastern Brazil. Methods:...
Menzies-Gow NJ.Certain individual animals appear predisposed to recurrent pasture-associated laminitis, but the exact mechanisms underlying their predisposition remain a fundamental question in laminitis research. The risk of endocrinopathic laminitis can be reduced if steps are taken to improve insulin sensitivity and reduce inflammation using strategies based on exercise and diet. Exercise has been shown to reduce insulin resistance and suppress inflammation, and dietary manipulation can significantly affect insulin sensitivity.
Carregaro AB, Freitas GC, Ribeiro MH, Xavier NV, Dória RG.Continuous-rate infusion (CRI) of drugs results in more stable plasma drug concentrations than administration of intermittent boluses, thus providing greater stability of physiological parameters. The aim of this study was to evaluate the physiologic and analgesic effects of the administration of morphine, butorphanol, tramadol or methadone by CRI in horses with induced synovitis of the radiocarpal joint. Results: Increased values of cardiorespiratory parameters and body temperature were observed in all groups after initiation of opioid administration, and these increases were sustained throug...
Thayer JF, Hahn AW, Pearson MA, Sollers JJ, Johnson PJ, Loch WE.High heart rate variability (HRV) has been associated with more efficient autonomic control, allowing more responsivity and sensitivity to changing environmental demands. Previous results from spectral analysis of interbeat intervals of equine heart rate (HR) indicated increased HRV, reflecting more effective vagal control of the heart. This study focuses on characterizing equine HR and HRV during increasing then decreasing physical demand. A non-invasive ambulatory monitoring system continuously records HR and HRV as horses exercise on a high speed equine treadmill at increasing then decreasi...
Dirikolu L, Lehner F, Nattrass C, Bentz BG, Woods WE, Carter WG, Karpiesiuk W, Jacobs J, Boyles J, Harkins JD, Granstrom DE, Tobin T.Diclazuril (4-chlorophenyl [2,6-dichloro-4-(4,5-dihydro-3H-3,5-dioxo-1,2,4-triazin-2-yl)pheny l] acetonitrile), is a benzeneacetonitrile antiprotozoal agent (Janssen Research Compound R 64433) marketed as Clinacox . Diclazuril may have clinical application in the treatment of Equine Protozoal Myeloencephalitis (EPM). To evaluate its bioavailability and preliminary pharmacokinetics in the horse we developed a sensitive quantitative high-pressure liquid chromatography (HPLC) method for diclazuril in equine biological fluids. MS/MS analysis of diclazuril in our HPLC solvent yielded mass spectral ...
Komosa M, Frackowiak H, Purzyc H, Wojnowska M, Gramacki A, Gramacki J.The study included 249 horses belonging to 3 horse breeds. Konik horses, comprising the first group, is an example of a breed similar to the extinct Tarpan. In our study, these horses were taken to be a primitive anatomical model of the horse body. The other groups comprised the Polish Half-bred horse and Thoroughbred horse. The biometric characteristics of the horses were compared based on 24 indices. The aim of the paper was to find a reduced set of indices that can be used to determine group membership of the horses. To do this, we used statistical methods to find the most important indices...
Hurtado C, Torres R, Pérez-Macchi S, Sagredo K, Uberti B, de Souza Zanatto DC, Machado RZ, André MR, Bittencourt P, Müller A.Anaplasma phagocytophilum is the causative agent of equine granulocytic anaplasmosis (EGA). This study aimed to perform serological and molecular surveys of A. phagocytophilum in thoroughbred horses from racecourses in Chile. Additionally, hematological findings related to A. phagocytophilum molecular positivity were addressed, and phylogenetic analysis of selected positive samples was performed. Complete blood count and msp2 gene real-time PCR were performed in 457 thoroughbred horses from three racecourses located in three different cities of Chile (Santiago, Viña del Mar and Concepción). ...
Ababneh MM, Troedsson MH.Real-time PCR was used to investigate the role of progesterone (P4) and oestradiol (E2) in regulation of endometrial cytosolic, secretory and calcium-independent phospholipase A2 (PLA2G4A, PLA2G2A and PLA2G6, respectively) gene expression. Ovariectomized mares underwent 6 days of E2 pre-treatment followed by 14 days of P4 supplementation. At the start of P4 treatment (Day 1), mares were assigned in a 2 × 2 factorial design to receive either E2 or vehicle starting on Day 11 and endometrial biopsy collection on either Day 14 when P4 concentrations remained high (>4 ng/ml) or Day 16 when P4 conc...
Divers TJ, Irby NL, Mohammed HO, Schwark WS.Information on antibiotic concentrations in the equine eye following systemic therapy is limited. Reports that Leptospira spp. are frequently present in the eyes of horses with recurrent uveitis, emphasises a need for studies on ocular concentrations of specific antibiotics. Objective: 1) Enrofloxacin, administered i.v. at 7.5 mg/kg bwt q. 24 h, results in aqueous humour concentrations greater than the reported minimum inhibitory concentration (MIC) for Leptospira pomona. 2) Aqueous humour paracentesis sufficiently disrupts the blood-aqueous humour barrier (BAB) to cause an increase in aqueous...
Ren X, Liu Y, Zhao Y, Li B, Bai D, Bou G, Zhang X, Du M, Wang X, Bou T, Shen Y, Dugarjaviin M.Interspecific hybridization often shows negative effects on hybrids. However, only a few multicellular species, limited to a handful of plants and animals, have shown partial genetic mechanisms by which hybridization leads to low fitness in hybrids. Here, to explore the outcome of combining the two genomes of a horse and donkey, we analyzed the whole-genome sequences from an parent-offspring trio using Illumina platforms. We generated 41.39× and 46.21× coverage sequences for the horse and mule, respectively. For the donkey, a 40.38× coverage sequence was generated and stored in our laborat...
Rankins EM, Wickens CL, McKeever KH, Malinowski K.Little published information exists on the horses in equine-assisted services (EAS), particularly their selection, longevity, and retirement. The purpose of this study was to characterize horses and procedures used in EAS. A pilot survey was developed using focus group discussions and distributed to Professional Association of Therapeutic Horsemanship, International (PATH Intl) centers in Florida ( = 45, Part I) before further modification and distribution to members of PATH Intl., American Hippotherapy Association (AHA), eagala, and Certified Horsemanship Association (CHA) ( = 26,000, Part II...
Filippo PAD, Duarte BR, Albernaz AP, Quirino CR.The objective of this study was to evaluate the effect of feed restriction on some physical and blood parameters in horses kept outdoors under natural conditions. Twenty horses were deprived of food for 48 h. They were closely monitored and examined, and blood samples were taken at the beginning (0) of the experiment and 6, 12, 18, 24, 30, 36, 42 and 48 hours afterward. During the experimental period, the control group (12 animals) had free access to water and hay, while the restricted group had free access to water only. Data were submitted to two-way analysis of variance with repeated measur...
Goehring LS, van Maanen C, Sloet van Oldruitenborgh-Oosterbaan MM.The presence of toxins or infectious agents combined with environmental factors in combination with a susceptible host can be the cause for neurological disease in groups of horses. During a 5 year observational period outbreaks of neurological diseases among horses were evaluated. Causes of occurring neurological diseases were equine botulism, lolitrem intoxications, equine herpesvirus type 1-associated myelo(encephalo)pathy, and encephalitis caused by (disseminated) Streptococcus equi subspecies equi infection. This article focuses on the first three syndromes because of their predominant in...
Postey RC, Appleyard GD, Kidney BA.Immunohistochemical (IHC) testing and electron microscopy have implicated Papillomavirus (PV) as the etiologic agent for equine papillomas and aural plaques, but Equine papillomavirus (EPV) DNA has yet to be demonstrated in these lesions by polymerase chain reaction (PCR). The purpose of this study was to evaluate formalin-fixed, paraffin-embedded tissues from naturally occurring cases of equine papillomas, aural plaques, and sarcoids for the presence of EPV DNA by means of PCR and for the presence of PV antigen by means of IHC testing. We used EPV-specific primers that amplified a region of 3...
De Clercq D, van Loon G, Tavernier R, Verbesselt R, Deprez P.To investigate effects of IV administration of propafenone for naturally occurring and experimentally induced chronic atrial fibrillation in horses. Methods: 2 horses with naturally occurring atrial fibrillation and 4 horses with pacing-induced atrial fibrillation. Methods: Horses received a bolus of propafenone (2 mg/kg, IV over 15 minutes). If atrial fibrillation persisted after 20 minutes, a continuous infusion of propafenone (7 microg/kg/min) was given for 120 minutes. Before, during, and after treatment, plasma propafenone concentrations, hematologic and serum biochemical values, and elec...
Sandow C, Fugler LA, Leise B, Riggs L, Monroe WT, Totaro N, Belknap J, Eades S.Laminitis has a considerable impact on the equine industry. Endocrinopathic laminitis is the most common form and affected horses often have hyperinsulinaemia due to an underlying metabolic disorder. Objective: The aim of this study was to determine if insulin weakens the structural integrity of digital lamellae and to develop an ex vivo model for the study of hyperinsulinaemia-induced lamellar failure. Methods: Ex vivo experiment. Methods: Biomechanical testing was used to assess the structural integrity of lamellar explants exposed to either medium alone (control) or medium supplemented with...
Voynick BT, Sweeney CR.Philippine polo and racing horses were examined for exercise-induced pulmonary hemorrhage after their competitive exercise. Exercise-induced pulmonary hemorrhage occurred in 11.1% of the polo horses and 64% of the racing horses. None of the horses had blood at the nostrils.
Elfenbein JR, Sanchez LC.Gastric ulcer disease is reported to be a significant cause of morbidity in foals, but the prevalence of ulcers in this population has not recently been evaluated. Objective: To determine the prevalence of gastric and duodenal ulceration in nonsurviving foals, and the association of ulceration with the body system of primary diagnosis. Secondary objectives were to evaluate a potential association between age and ulcer prevalence and to evaluate the use of antacid medication in the neonatal hospital population during the study years. Methods: Necropsy records were searched for all equine access...
Rüfenacht S, Straub R, Steinmann B, Winand N, Bidaut A, Stoffel MH, Gerber V, Wyder M, Müller E, Roosje PJ.Hereditary equine dermal asthenia (HERDA) is an autosomal recessive skin disease that affects predominantly Quarter Horses and related breeds. Typical symptoms are easy bruising and hyperextensible skin on the back. The prognosis is guarded, as affected horses cannot be ridden normally and are often euthanised. In the Quarter Horse, HERDA is associated with a mutation in cyclophilin B (PPIB), an enzyme involved in triple helix formation of collagen. Here we describe the case of a Swiss Warmblood filly with symptoms of HERDA without PPIB-mutation and in which we also could exclude Ehlers-Danlos...
Navas de Solís C, Reef VB, Slack J, Jose-Cunilleras E.To evaluate horses with atrial fibrillation for hypercoagulability; plasma D-dimer concentrations, as a marker of a procoagulant state; and a relationship between coagulation profile results and duration of atrial fibrillation or presence of structural heart disease. Methods: Case-control study. Methods: Plasma samples from 42 horses (25 with atrial fibrillation and 17 without cardiovascular or systemic disease [control group]). Methods: Results of hematologic tests (ie, plasma fibrinogen and D-dimer concentrations, prothrombin and activated partial thromboplastin times, and antithrombin activ...
