Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Haggett EF, Foote AK, Head MJ, McGladdery AJ, Powell SE.A 4-week-old Thoroughbred filly foal with a history of sepsis was evaluated for right hindlimb lameness. Bilateral femoropatellar and femorotibial joint effusions were detected. Ultrasonography and radiography of the right stifle revealed signs of joint collapse and periarticular swelling. Computed tomography revealed abnormalities in the bone density of the medial femoral condyle of the right hindlimb and lateral femoral condyle of the left hindlimb. Euthanasia was recommended based on the severity of the lesions. Gross and microscopic examinations revealed extensive separation of the articul...
Borchers A, Wilkins PA, Marsh PM, Axon JE, Read J, Castagnetti C, Pantaleon L, Clark C, Qura'n L, Belgrave R, Trachsel D, Levy M, Bedenice D....Admission L-lactate concentration is a useful and commonly measured biomarker not previously prospectively evaluated in a large multicentre study of critically ill neonatal foals. Objective: To evaluate overall outcome and the association of survival and L-lactate concentration at admission ([LAC]ADMIT) by periparturient history, presenting complaint and clinicians' major diagnosis for ill neonatal foals. Methods: Thirteen university and private equine referral hospitals enrolled 643 foals over the 2008 foaling season. Case details, historical, clinical and clinicopathological data were entere...
Holdstock NB, Allen VL, Fowden AL.During the switch from parenteral to enteral nutrition at birth, endocrine glands such as the pancreas must assume a glucoregulatory role for the first time if the neonate is to survive the transition to extrauterine life. Objective: To determine the adaptations in pancreatic endocrine function during the neonatal period in term pony foals delivered by different methods. Methods: By measuring insulin and glucagon concentrations, pancreatic alpha and beta cell responses to exogenous glucose (0.5 g/kg bwt) and arginine (100 mg/kg bwt) and to endogenous muzzling for 90 min were determined periodi...
Himler M, Hurcombe SD, Griffin A, Barsnick RJ, Rathgeber RA, MacGillivray KC, Toribio RE.Hypothalamic-pituitary-thyroid (HPT) axis dysfunction is associated with morbidity and mortality in critically ill people. To date, investigations of HPT axis in critically ill foals are limited. Objective: To document the occurrence of low thyroid hormone concentrations (presumptive nonthyroidal illness syndrome; NTIS) in critically ill newborn foals and investigate whether NTIS is associated with severity of disease and outcome. Objective: NTIS occurs frequently in foals with sepsis and is associated with sepsis score and outcome. Reverse T3 (rT3) concentrations will be increased in septic f...
Pisano MB, Seco MP, Ré VE, Farías AA, Contigiani MS, Tenorio A.Venezuelan Equine Encephalitis (VEE) complex belongs to alphavirus genus in the family Togaviridae. Several species of this complex are pathogenic to humans. VEE infections can produce severe or mild disease, and many cases remain undiagnosed. A specific and sensitive reverse transcriptase nested polymerase chain reaction (RT-Nested PCR) method was developed for the detection of all VEE subtypes, including Rio Negro Virus (RNV) (subtype VI), which circulates only in Argentina. Degenerated primers were designed and thermal cycling parameters were standardized. This technique is suitable for rap...
McGowan TW, Pinchbeck GP, McGowan CM.Equine pituitary pars intermedia dysfunction (PPID) is an ageing-related neurodegenerative disorder. The prevalence and risk factors for PPID using seasonally adjusted basal adrenocorticotropic hormone (ACTH) concentrations in aged horses have not been previously reported. Objective: To determine the prevalence, risk factors and clinical signs predictive for PPID in a population of horses aged ≥ 15 years in Queensland, Australia. Methods: Owner-reported data was obtained using a postal questionnaire distributed to an equestrian group. A subgroup of surveyed owners were visited and a veterina...
Funk RA, Wooldridge AA, Stewart AJ, Behrend EN, Kemppainen RJ, Zhong Q, Johnson AK.Equine metabolic syndrome (EMS) is an increasingly recognized problem in adult horses. Affected horses are often obese and predisposed to the development of laminitis, especially in the spring and summer months. In addition, in the summer and fall months, increases in endogenous insulin concentrations, a marker of EMS, have been reported. Objective: The purpose of this study was to evaluate seasonal changes in results of the combined glucose-insulin tolerance test (CGIT), a diagnostic test for EMS. Methods: Nine healthy, aged horses with no history of laminitis and no clinical signs of EMS. Me...
Kelmer G, Bell GC, Martin-Jimenez T, Saxton AM, Catasus C, Elliot SB, Meibohm B.Previous studies have shown that regional limb perfusion (RLP) using the palmar digital (PD) vein delivers therapeutic concentration of amikacin to the distal limb. Our hypothesis was that using the cephalic and saphenous veins for RLP will enable delivery of therapeutic concentrations of amikacin to the distal limb. Nineteen healthy horses participated in the study. The cephalic, saphenous, or PD vein was used to perfuse the limb with amikacin. Two grams of amikacin was used for RLP using the saphenous and the cephalic veins, and one gram was used in the PD vein. Synovial samples were collect...
Būda V, Mozūraitis R, Kutra J, Borg-Karlson AK.Previously it was shown that m- and p-cresols in the urine of mares exhibits a temporally reproducible pattern that is dependent on ovarian activity and, thus, provides information about the timing of ovulation. New behavioral data demonstrate 1) that stallions spend significantly more time sniffing p-cresol as compared to o-, and m-cresols, and, 2) that the extent of stallions' erections differ significantly in response to different types of samples. The lowest erection level was recorded for the pure-water control, a moderate erection level was elicited by the urine of diestrous mares, and t...
Cuervo-Arango J, Newcombe JR.The most common pathological anovulatory condition that occurs spontaneously during the breeding season in the mare is the haemorrhagic anovulatory follicle (HAF). A relatively high proportion of mares, soon after ovulation, develop a corpus haemorrhagicum (CH) with a central lacuna. This type of corpora lutea may resemble an HAF, which may complicate the accurate diagnosis of ovulation. The main objective of this study was to compare the ultrasound data of mares examined frequently with HAFs and CHs to elucidate whether it is possible to distinguish them from each other. A total of 135 ovulat...
Burgess HJ, Lockerbie BP, Czerwinski S, Scott M.A 12-year-old female Argentinean Warmblood mare was evaluated because of respiratory noise. The horse resided in Calgary, Alberta, Canada, but had been imported from Argentina 28 months prior to presentation. Endoscopy of the upper respiratory tract revealed a single polypoid mass on the left arytenoid. The mass was surgically excised and was diagnosed histologically as rhinosporidiosis. Polymerase chain reaction and DNA sequencing were used to confirm the etiological agent. Four weeks postoperatively, endoscopy was repeated, revealing recurrence of the original lesion with multiple additional...
Setterbo JJ, Fyhrie PB, Hubbard M, Upadhyaya SK, Stover SM.Racetrack surface is a risk factor for Thoroughbred racehorse injury and death that can be engineered and managed. To investigate the relationship between surface and injury, the mechanical behaviour of dirt and synthetic track surfaces must be quantified. Objective: To compare dynamic properties of a dirt and a synthetic surface in situ using a track-testing device designed to simulate equine hoof impact; and to determine the effects of impact velocity, impact angle and repeated impact on dynamic surface behaviour. Methods: A track-testing device measured force and displacement during impact ...
Manole V, Laurinmäki P, Van Wyngaardt W, Potgieter CA, Wright IM, Venter GJ, van Dijk AA, Sewell BT, Butcher SJ.African horsesickness (AHS) is a devastating disease of horses. The disease is caused by the double-stranded RNA-containing African horsesickness virus (AHSV). Using electron cryomicroscopy and three-dimensional image reconstruction, we determined the architecture of an AHSV serotype 4 (AHSV-4) reference strain. The structure revealed triple-layered AHS virions enclosing the segmented genome and transcriptase complex. The innermost protein layer contains 120 copies of VP3, with the viral polymerase, capping enzyme, and helicase attached to the inner surface of the VP3 layer on the 5-fold axis,...
Proops L, McComb K.It has recently been shown that some non-human animals can cross-modally recognize members of their own taxon. What is unclear is just how plastic this recognition system can be. In this study, we investigate whether an animal, the domestic horse, is capable of spontaneous cross-modal recognition of individuals from a morphologically very different species. We also provide the first insights into how cross-modal identity information is processed by examining whether there are hemispheric biases in this important social skill. In our preferential looking paradigm, subjects were presented with t...
Signer-Hasler H, Flury C, Haase B, Burger D, Simianer H, Leeb T, Rieder S.The molecular analysis of genes influencing human height has been notoriously difficult. Genome-wide association studies (GWAS) for height in humans based on tens of thousands to hundreds of thousands of samples so far revealed ∼200 loci for human height explaining only 20% of the heritability. In domestic animals isolated populations with a greatly reduced genetic heterogeneity facilitate a more efficient analysis of complex traits. We performed a genome-wide association study on 1,077 Franches-Montagnes (FM) horses using ∼40,000 SNPs. Our study revealed two QTL for height at withers on c...
Tallmadge RL, Stokol T, Gould-Earley MJ, Earley E, Secor EJ, Matychak MB, Felippe MJ.Fell Pony syndrome (FPS) is a fatal immunodeficiency that occurs in foals of the Fell Pony breed. Affected foals present with severe anemia, B cell lymphopenia, and opportunistic infections. Our objective was to conduct a prospective study of potential FPS-affected Fell Pony foals to establish clinical, immunological, and molecular parameters at birth and in the first few weeks of life. Complete blood counts, peripheral blood lymphocyte phenotyping, and serum immunoglobulin concentrations were determined for 3 FPS-affected foals, 49 unaffected foals, and 6 adult horses. In addition, cytology o...
Gürelli G, Göçmen B.Species composition and distribution of intestinal ciliates were investigated in the feces from 15 racing horses living near Izmir, Turkey. Thirty-seven species belonging to 21 genera were identified. Although no new species were observed, this is the first report on intestinal ciliates in racing horses living in Turkey. The mean number of ciliates was 26.4 ± 13.9 × 10(4) cells ml(-1) of feces and the mean number of ciliate species per host was 18.8 ± 7.1. No ciliates were observed in one horse. Bundleia and Polymorphella were found to be the two dominant genera, occurring in high proportio...
Wang CC, Hartmann-Fischbach P, Krueger TR, Wells TL, Feineman AR, Compton JC.3,4-Methylenedioxypyrovalerone (MDPV) is a psychoactive drug with potent stimulant properties and potential for abuse and drug dependency. MDPV was recently classified as a Class I drug by Racing Commissioners International, indicating that it is a banned substance in equine athletes because it lacks therapeutic value in horses. To enforce this ban, a sensitive and fast liquid chromatography-tandem mass spectrometry method was needed. It is for this reason that this method was developed for quantification and confirmation of MDPV in equine plasma. Sample preparation involved liquid-liquid extr...
Noronha LE, Antczak DF.Pregnant mares demonstrate a reduction in cytotoxic T lymphocyte (CTL) reactivity against cells from the breeding stallion. We investigated whether this effect is limited to activity against paternal major histocompatibility complex (MHC) antigens, and whether it occurs during MHC-compatible pregnancy. Methods: Mares were mated to carry MHC-compatible or MHC-incompatible pregnancies. CTL activity of these mares when pregnant and non-pregnant was measured against cells from horses with MHC haplotypes unrelated to the mare or breeding stallion. Results: While carrying MHC-incompatible pregnancie...
Frellstedt L, McKenzie HC, Barrett JG, Furr MO.Endotoxemia is responsible for severe illness in horses. Individuals can become clinically unresponsive to the endotoxin molecule after an initial exposure; a phenomenon referred to as 'endotoxin tolerance' (ET). ET has been observed clinically in horses in vivo; however, cytokine expression associated with ET has not been investigated. The purpose of this study was to develop and validate a method for inducing ET in equine peripheral blood mononuclear cells (PBMC) in vitro, and to describe selected cytokine responses which are associated with ET. ET was induced by culturing cells with three c...
Marqués FJ, Hehenberger E, Dickinson R, Wojnarowicz C, Lohmann K.A 9-year-old, 1494-lb (679-kg) Quarter horse gelding in good body condition was admitted to the Veterinary Teaching Hospital, Western College of Veterinary Medicine (WCVM), University of Saskatchewan, for evaluation and treatment of acute respiratory distress. On a trail ride 26 days before presentation, the gelding had been exposed to a horse with clinical signs of an upper respiratory tract infection. The gelding performed well on the trail ride but, 4 days later, developed a mild swelling in the retropharyngeal area and a slight bilateral mucoid nasal discharge. The gelding was examined at ...
Johnson AK, Roberts JF, Hagan A, Wilborn RR, Dujovne G, Sells SF, Donahue JM.A 25-year-old pregnant American Quarter Horse mare presented with a 1-week history of progressively worsening vaginal discharge. Transrectal ultrasound revealed increased thickness of the combined uterus and placenta with evidence of chorioallantoic edema but no placental separation. A thickened amnion was visible on transabdominal ultrasound. Abortion occurred 2 days after presentation despite medical treatment. At necropsy, the chorioallantois had variable but diffuse thickening with focally extensive browning of the chorionic surface in the right horn and adjacent body. There were fluid-fil...
Dupuis MC, Zhang Z, Durkin K, Charlier C, Lekeux P, Georges M.We used the data from a recently performed genome-wide association study using the Illumina Equine SNP50 beadchip for the detection of copy number variants (CNVs) and examined their association with recurrent laryngeal neuropathy (RLN), an important equine upper airway disease compromising performance. A total of 2797 CNVs were detected for 477 horses, covering 229 kb and seven SNPs on average. Overlapping CNVs were merged to define 478 CNV regions (CNVRs). CNVRs, particularly deletions, were shown to be significantly depleted in genes. Fifty-two of the 67 common CNVRs (frequency ≥ 1%) we...
Brooks DE, Plummer CE, Mangan BG, Ben-Shlomo G.To describe clinical findings in equine subepithelial keratomycosis (SEK). Methods: Retrospective medical records study. Methods: Medical records of horses that had subepithelial keratomycosis (SEK) at the University of Florida Veterinary Medical Center from 2007 to 2011 were reviewed. Methods: Data collected from the medical records included signalment, clinical descriptions of ocular lesions, diagnostic techniques, and therapeutic outcomes. Results: Twenty-one horses, consisting of three Quarter horse geldings, two Morgan geldings, one Morgan mare, two Arabian mares, three Arabian geldings, ...
Douthit TL, Bormann JM, Gradert KC, Lomas LW, DeWitt SF, Kouba JM.This experiment was conducted to evaluate if consumption of endophyte-infected fescue alters digital circulation in the distal thoracic limb of the horse and to assess if soundness of the hooves of horses is affected by consumption of endophyte-infected fescue. Twelve American Quarter Horses (mean initial BW 459 ± 31 kg), 6 mares and 6 geldings, were used in this 90-d study that comprised high-endophyte (E+) and low-endophyte (E-) treatment groups. Fescue seed was integrated into the E+ diet at a rate sufficient to bring total ergovaline to 200 μg/kg, and endophyte-free fescue seed was incor...
Fox AE, Bailey SR, Hall EG, St Peter CC.Biting and chewing by horses on crossties can result in injury to the handler and damage to equipment. Operant-conditioning techniques have been used to train horses and could be used to reduce or eliminate undesirable biting and chewing. Presently, a differential-reinforcement-of-other-behavior (DRO) schedule, in the context of a reversal design, was effective in reducing biting and chewing in two horses. In DRO schedules, a reinforcer is delivered contingent on the absence of a target behavior for a specified interval. Positive-reinforcement procedures offer an alternative to aversive-contro...
Schurink A, Ducro BJ, Bastiaansen JW, Frankena K, van Arendonk JA.Insect bite hypersensitivity (IBH) is the most common allergic disease present in horses worldwide. It has been shown that IBH is under genetic control, but the knowledge of associated genes is limited. We conducted a genome-wide association study to identify and quantify genomic regions contributing to IBH in the Dutch Shetland pony population. A total of 97 cases and 91 controls were selected and matched on withers height, coat colour and pedigree to minimise the population stratification. A blood sample was collected from participating Shetland pony mares, their IBH phenotype was scored and...
Miller RI, Campbell RS.A survey of granulomatous and neoplastic diseases of the skin of horses of tropical north Queensland was carried out during the period 1970-1980. Of 338 horses affected, 46.4% suffered from equine fibrosarcoma (sarcoid), 30.2% from phycomycosis, 7.4% from squamous cell carcinoma, 6.8% from other tumours, 4.7% from cutaneous habronemiasis and 4.4% from exuberant granulation tissue. Most specimens were submitted during the first half of the year after the wet monsoonal season and significantly more diseases originated during the first quarter. There was minor variations with breed, age and sex s...
Gacem S, Catalán J, Valverde A, Soler C, Miró J.In order to optimize the donkey sperm motility analysis by the CASA (Computer Assisted Sperm Analysis)-Mot system, twelve ejaculates were collected from six jackasses. Capillary loaded chamber (CLC), ISASD4C depths 10 and 20 µm, ISASD4C Leja 20 and drop displacement chamber (DDC), Spermtrack (Spk) depths 10 and 20 µm were used. Sperm kinematic variables were evaluated using each chamber and a high-resolution camera capable of capturing a maximum of 500 frames/second (fps). The optimum frame rate (OFR) (defined according to curvilinear velocity-VCL) was dependent on chamber type. The highest ...
Lawton K, Keller SM, Barnum S, Arredondo-Lopez C, Spann K, Pusterla N.While some companion animals have been shown to be susceptible to SARS-CoV-2, their role in the COVID-19 pandemic has remained poorly investigated. Equids are susceptible to SARS-CoV-2 based on the similarity of the human ACE-2 receptor and reports of infection. Clinical disease and prevalence factors associated with SARS-CoV-2 infection in equids have not yet been investigated. The aim of this study was to determine the seroprevalence of SARS-CoV-2 and selected prevalence factors in 1186 equids presented for various conditions to a Veterinary Medical Teaching Hospital over a two-year period. ...
Moore RM, Hance SR, Hardy J, Moore BR, Embertson RM, Constable PD.Colonic luminal pressure (median, range) measured during ventral midline celiotomy in 69 horses with strangulating obstruction (SO) of the large colon (SO; > or = 270 degrees large colon volvulus; 27 cm H2O: 2 to 80 cm H2O) was greater (P = .0023) than that measured in 37 horses with nonstrangulating obstruction (NSO) of the large colon (NSO; < or = 180 degrees volvulus or a nonstrangulating displacement; 18 cm H2O; 6 to 46 cm H2O). Sixty-five percent (45 of 69) of horses with SO and all horses with NSO survived. Survival analysis was restricted to 59 horses with large-colon SO that survived t...
Ziegler AL, Blikslager AT.Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to manage a wide variety of conditions in horses, including management of colic. Flunixin meglumine is by far the most commonly used drug in the control of colic pain and inflammation and has become a go-to for not only veterinarians but also horse-owners and nonmedical equine professionals. NSAID use, however, has always been controversial in critical cases due to a high risk of adverse effects associated with their potent cyclo-oxygenase (COX) inhibition. There are two important COX isoenzymes: COX-1 is generally beneficial for ...
Oncel T, Vural G, Gicik Y, Arslan MO.This study was carried out in order to detect antibodies to Babesia (Theileria) equi in the local breed of horses in the province of Kars, Turkey. A total of 108 serum samples from apparently healthy horses in eight villages were examined for B. equi antibodies by an indirect immunofluorescent antibody test (IFAT). Of the 108 samples tested, 27 (25%) were found to be seropositive. The horses sampled in Aydinalan village had the highest prevalence (50.0%) of Babesia equi infection while the lowest prevalence was found among horses from Bayraktar village (12.5%). Statistically significant differ...
Waller A., head of bacteriology at the AHT, describes the causative agent of strangles in horses, and discusses progress with the latest research aimed at improving vaccines against this global disease.
Mogielnicka-Brzozowska M, Fraser L, Dziekońska A, Gackowska K, Sobiewska M, Kuzborska A, Majewska AM, Filipowicz K, Kordan W.The aim of this study was to identify the proteoforms of albumin and kallikrein in stallion seminal plasma (SP), and to determine their correlations with sperm motility parameters. The experimental material consisted of ejaculates from 8 stallions, which were collected during the breeding and non-breeding seasons (BS and NBS, respectively). SP proteins were identified by 2-D PAGE and mass spectrometry (MALDI TOT/TOF MS). Sperm motility parameters were analyzed using the CASA system. Protein expression (integrated optical density-IOD) of albumin proteoforms 1 (ALB 1) and 2 (ALB 2) and kallikrei...
Ryan CT, Schaer BL, Nunamaker DM.A device is needed to safely and wirelessly evaluate accelerations experienced by the horse hoof under a variety of surface conditions with the horse exercising at training or racing speeds. Objective: To develop a miniaturised wireless data acquisition system (WDAS) which reliably records hoof accelerations and the times over which they occur in a minimally invasive manner in the exercising Thoroughbred. Methods: The following criteria were set for device development: production of a lightweight and minimally invasive system, which provides an adequate acceleration range, appropriate frequenc...
Villas-Boas JD, Dias DP, Trigo PI, Almeida NA, de Almeida FQ, de Medeiros MA.Startle is a fast response elicited by sudden acoustic, tactile, or visual stimuli in a variety of animals and in humans. As the magnitude of startle response can be modulated by external and internal variables, it can be a useful tool to study reaction to stress. Our study evaluated whether acupuncture can change cardiac autonomic modulation (heart rate variability); and behavioural (reactivity) and endocrine (cortisol levels) parameters in response to startle. Brazilian Sport horses (n = 6) were subjected to a model of startle in which an umbrella was abruptly opened near the horse. Before s...
Donnelly J, Joyner LP, Frank C.Racehorses imported into Kuwait were tested for serum antibodies to Babesia equi and B. caballi by complement fixation (CF) and indirect fluorescent antibody (IFA) tests. The prevalence of B. equi was high (77.1% by IFA) whereas that of B. caballi was much lower (11.4%). Data for B. equi showed that infection was acquired after about 6 months at risk and that in the following 12 months animals had antibody levels detectable by both CF and IFA tests by 24 months the CF reaction was no longer detectable. Estimates of incidence and inoculation rates were calculated and found to be consistent with...
Nakazawa M, Sugimoto C, Isayama Y.The selective isolation of R. equi in NANC medium was made by quantitative culture of the organism in the feces. R. equi was observed in the feces of all the mares and foals investigated. The mean viable count of R. equi organisms in 1 gram of feces was 8.42 X 10(2) in the mares and 7.57 X 10(2) in the foals, and its 95% confidence limits were in a range of 6.48 X 10(2) to 1.09 X 10(3) and 4.19 X 10(2) to 1.37 X 10(3), respectively. This result indicates that R. equi is a member of the normal intestinal flora in the horse.
Holland AJ, Roy GT, Goh V, Ross FI, Keneally JP, Cass DT.To identify the frequency, spectrum and outcome of horse-related injuries in children. Methods: Retrospective case series of horse-related injuries in children admitted to the Children's Hospital at Westmead (CHW) from January 1988 to December 1999, the John Hunter Children's Hospital (JHCH) from January 1991 to December 1997 and deaths reported to the New South Wales Paediatric Trauma Death (NPTD) Registry from January 1988 to December 1999. Methods: Circumstances of injury; helmet use; adult supervision; type and number of injuries identified. Results: 232 children were admitted with horse-r...
Hinrichs K, Choi YH, Norris JD, Love LB, Bedford-Guaus SJ, Hartman DL, Velez IC.To evaluate the efficiency of foal production following intracytoplasmic sperm injection (ICSI) and blastocyst culture of oocytes from mares that died or were euthanized under field conditions. Methods: Prospective case series. Methods: 16 mares (age, 3 to 19 years) that died or were euthanized for various causes. Methods: Ovaries were collected immediately before euthanasia (n = 10) or after death (6). Ovaries were transported to the laboratory for oocyte recovery (15 mares), or oocytes were recovered at a remote location and shipped to the laboratory (1). Oocytes underwent ICSI, and presumpt...
Bousquet-Mélou A, Schneider M, El Garch F, Broussou DC, Ferran AA, Lallemand EA, Triboulloy C, Damborg P, Toutain PL.Marbofloxacin (MBX), a fluoroquinolone (FQ), is considered as a critical antibiotic requiring antimicrobial susceptibility testing (AST) for prudent use. No clinical breakpoint (CBP) currently exists to interpret the results of such tests in horses. Objective: To compute PK/PD cut-offs (PK/PDCO ) that is one of the three minimum inhibitory concentrations (MICs) considered establishing a CBP for antimicrobial susceptibility test interpretation. Methods: A meta-analysis conducted by combining five sets of previously published pharmacokinetic data, obtained in clinical and nonclinical settings. M...
McGreevy PD, Hawson LA, Habermann TC, Cattle SR.Recorded in several species including humans, geophagia or soil eating has been observed in both wild and domesticated horses and has generally been regarded as an indication of nutritional deficiency or "boredom". Studies of soils consumed by different species have led to several theories as to the identity of soil constituents that stimulate geophagia. In this study, geochemical analysis of 13 equine geophagic sites from different parts of Australia was undertaken. Significantly larger concentrations of iron and copper were found in soil samples from geophagic sites when compared to paired c...
Brosnahan MM, Damiani A, van de Walle G, Erb H, Perkins GA, Osterrieder N.Available vaccines fail to induce lasting and protective immunity to equine herpesvirus 1 (EHV-1) associated diseases. RNA interference is a novel approach showing promise for therapeutic use in outbreak situations. This study examined the effect of small interfering RNA (siRNA) on clinical signs as well as the presence of live virus and viral DNA in nasal secretions and peripheral blood mononuclear cells (PBMCs) in horses experimentally infected with EHV-1. siRNA targeting two EHV-1 genes (glycoprotein B and the origin binding protein) was administered 12h before and 12h after intranasal infe...
Sasaki N, Yamada H.To evaluate the visibility of various portions of the small intestine in healthy horses using capsule endoscopy. Methods: Six healthy, conscious adult Thoroughbreds were restrained and an endoscopic capsule (PillCam SB capsule) was inserted into the oesophagus using an intranasal catheter aided by a guide wire. Water (500 mL) flushed the capsule down the gastrointestinal tract. Data were collected and stored in the recorder of the endoscopic system for 6 hours after capsule insertion and the images were evaluated using an image reader and scored using a visual analogue scale. Results: Capsule ...
DiPietro JA, Lock TF, Todd KS, Reuter VE.Twenty ponies less than 18 months of age and infected with Parascaris equorum were treated with either 0.2 mg of ivermectin/kg of body weight (n = 10) or a placebo (n = 10; controls). Five control and 5 ivermectin-treated ponies were euthanatized 14 and 35 days after treatment, respectively. At necropsy, the small intestinal contents, lungs, and liver were examined for larvae and/or adult P equorum. Significantly (P less than 0.02) higher mean total numbers of P equorum were found in the small intestinal contents of the controls on day 14 (51) and on day 35 (21) than in the ivermectin-treated ...
Olsen SC, Coyne CP, Lowe BS, Pelletier N, Raub EM, Erickson HH.Four hours prior to exercise on a high-speed treadmill, 4 dosages of furosemide (0.25, 0.50, 1.0, and 2.0 mg/kg of body weight) and a control treatment (10 ml of 0.9% NaCl) were administered IV to 6 horses. Carotid arterial pressure (CAP), pulmonary arterial pressure (PAP), and heart rate were not different in resting horses before and 4 hours after furosemide administration. Furosemide at dosage of 2 mg/kg reduced resting right atrial pressure (RAP) 4 hours after furosemide injection. During exercise, increases in treadmill speed were associated with increases in RAP, CAP, PAP, and heart rate...
Hannan MA, Murase H, Sato F, Tsogtgerel M, Kawate N, Nambo Y.The peripheral blood concentrations of insulin-like peptide 3 (INSL3) have been detected in many mammalian species, but the level of INSL3 in horse remains unknown. The objectives were to develop a time-resolved fluorescence immunoassay (TRFIA) to detect INSL3 concentrations from horse blood as well as to determine the age-related and seasonal changes of plasma concentrations of INSL3 and testosterone from birth to early-puberty in Thoroughbred male horse (n = 11). Monthly blood sample and measurement of body weight, height, chest and cannon bone size were done from birth until 16 mo. Th...
Böhnel H, Wernery U, Gessler F.Botulism is caused by different types of Clostridium botulinum, a soil bacterium. Equine grass sickness (equine dysautonomia) is suspected of being a clinical form of this disease. On a stud where this disease occurred twice within 8 months, grass and soil samples and necropsy specimens of one horse were tested for the presence of bacterial forms and toxin of C. botulinum. Different types and type mixtures (A-E) of C. botulinum and botulinum neurotoxin were found. For the first time, it has been shown that green grass blades contain botulinum toxin. The results support the hypothesis that equi...
Pauwels FE, McClure SR, Amin V, Van Sickle D, Evans RB.To measure changes in the modulus of elasticity (E) and describe histologic findings after extracorporeal shock wave therapy and radial pressure wave therapy on equine cortical bone specimens. Methods: 16 bone specimens from the proximodorsal cortex of an equine third metacarpal or metatarsal bone. Methods: Baseline E was determined by the density (p) and unidirectional ultrasound transmission velocity (C) of each specimen according to the equation E = pC2. Eight specimens were treated with 500 pulses of 0.15 mJ/mm2 of extracorporeal shock wave therapy, and 8 specimens were treated with 500 pu...
Explore (New York, N.Y.)June 20, 2006
Volume 2, Issue 3 264-268 doi: 10.1016/j.explore.2006.03.013
Haylock PJ, Cantril CA.Nearly 10 years ago, I looked at a poster exhibit for a nonprofit organization's camping experience for cancer survivors. One of the images in particular remains with me to this day. It was of an elderly man wearing a cowboy hat and the great grin on his wrinkled face as he stood next to a beautiful sorrel horse. The woman at the poster told me the story behind the picture: The man had advanced cancer and had already entered a hospice program, even though he was still physically active. He'd told many people that his biggest regret in life was that he'd never gotten to ride a horse. The photog...
Silva CJFL, Trindade KLG, Cruz RKS, Manso HECCC, Coelho CS, Filho JDR, Nogueira CEW, Aragona F, Fazio F, Manso Filho HC.Erosions and gastric ulcers may be present in horses at any age and under different conditions of rearing and handling. In tropical regions, horses can feed on fruits rich in soluble carbohydrates, such as mangoes, but little is known about how these foods interact with their digestive systems. To test the hypothesis that the ingestion of ripe mangoes with peels could cause disturbances in the digestive processes of horses, an experiment was developed to monitor animals that had free access to ripe mangoes in their pasture areas. Horses (purebred Arabians, n = 5; ~340 kg, ~13 years) were evalu...
Pakkanen SA, Raekallio MR, Mykkänen AK, Salla KM, de Vries A, Vuorilehto L, Scheinin M, Vainio OM.To investigate MK-467 as part of premedication in horses anaesthetized with isoflurane. Methods: Experimental, crossover study with a 14 day wash-out period. Methods: Seven healthy horses. Methods: The horses received either detomidine (20 μg kg(-1) IV) and butorphanol (20 μg kg(-1) IV) alone (DET) or with MK-467 (200 μg kg(-1) IV; DET + MK) as premedication. Anaesthesia was induced with ketamine (2.2 mg kg(-1) ) and midazolam (0.06 mg kg(-1) ) IV and maintained with isoflurane. Heart rate (HR), mean arterial pressure (MAP), end-tidal isoflurane concentration, end-tidal carbon ...
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 ...
Roth P, Stanley J, Chamoun-Emanuelli A, Whitfield-Cargile C, Coleman M.To compare the inflammatory response of murine macrophages exposed to the enteric microbiome of obese horses versus nonobese horses. Methods: Fecal samples from 12 obese horses (body condition score ≥ 7/9) and 12 nonobese horses (body condition score 4 to 5/9) with similar dietary management. Methods: Fecal supernatant was prepared from frozen fecal samples. RAW 264.7 macrophage cells were exposed to the fecal extract. Inflammatory cytokine (interleukin-1β, tumor necrosis factor-α, and interleukin-6) gene expression was quantified via real-time quantitative reverse transcription PCR assay,...
