Equine Science encompasses the study of horses and their management, health, and performance. This field integrates various scientific disciplines such as biology, genetics, nutrition, physiology, and veterinary medicine to understand and improve the well-being and capabilities of horses. Areas of focus include equine anatomy, reproduction, behavior, and disease prevention. Research in equine science aims to enhance horse care, optimize training and performance, and address health challenges. This page compiles peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine science, providing insights into the latest advancements and methodologies in the field.
Marlo TL, Giuliano EA, Sharma A, Mohan RR.To develop an ex vivo equine corneal organ culture model. Specifically, to assess the equine cornea's extracellular matrix and cellularity after 7 days using two different culture techniques: either (i) immersion system or (ii) air/liquid interface system, to determine the best ex vivo equine corneal model. Methods: Fourteen healthy equine corneas of various breeds. Methods: Equine corneas with 2 mm of perilimbal sclera were freshly harvested from 7 horses undergoing humane euthanasia. One corneal-scleral ring (CSR) from each horse was randomly placed in the (i) immersion condition organ cultu...
Chen Y, Caporali E, Stewart M.Bone morphogenetic protein 2 (BMP-2) is critical for skeletal and cartilage development, homeostasis and repair. This study was conducted to clone and characterize equine BMP-2, develop expression constructs for equine BMP-2, and to determine whether BMP-2 can stimulate chondrogenesis of equine synovial membrane-derived progenitor cells (SMPC). Methods: Equine BMP-2 cDNA was amplified from chondrocyte RNA, and then transferred into an expression plasmid and adenoviral vector. Effective expression of equine BMP-2 was confirmed using a BMP reporter cell line. SMPC were isolated from synovium, ex...
Guillaume-Vasselin V, Lemaitre L, Dhondt KP, Tedeschi L, Poulard A, Charreyre C, Horvat B.Hendra virus (HeV) is an emerging zoonotic pathogen, which causes severe respiratory illness and encephalitis in humans and horses. Since its first appearance in 1994, spillovers of HeV from its natural reservoir fruit bats occur on almost an annual basis. The high mortality rate in both humans and horses and the wide-ranging reservoir distribution are making HeV a serious public health problem, especially for people exposed to sick horses. This study has aimed to develop an efficient low-cost HeV vaccine for horses based on Canarypox recombinant vector expressing HeV glycoproteins, attachment...
McKeever KH.An increasing percentage of the equine population is more than 15 years old, many performing various athletic activities into their 20s. Studies of aged humans have led to a fine tuning of exercise prescription to promote fitness while preventing adverse and potentially dangerous effects of excessive exercise. However, limited data exist regarding the exercise capacity of aged horses. This article presents an overview of published studies on aging-induced decreases in physiologic function and exercise capacity in the horse. The information presented can be used as a guide for exercise prescrip...
Ireland JL.Gerontology has become increasingly important in equine veterinary medicine, with aged animals representing a significant proportion of the equine population. Horses are defined as geriatric or aged from age 15 years onwards but can have a life span of more than 40 years. Despite a high level of owner concern for the well-being of their geriatric animal, provision of preventive health care may be suboptimal. Owners seem to under-recognize some of the most prevalent diseases identified in geriatric horses. This review focuses on the demographic characteristics of the equine geriatric populati...
Anderson S, Meints K.Equine-assisted activities and therapies are increasing in popularity for treatment of ASD symptoms. This research evaluated effects of a 5-week programme of therapeutic riding on social functioning of children/adolescents (N = 15) with ASD. The effectiveness of the programme was evaluated using the autism spectrum quotient, the Vineland Adaptive Behaviour Scale and the empathising and systemising quotient. Results established that the TR intervention increased empathising and reduced maladaptive behaviours. The findings also indicated that specific adaptive behaviours like socialization and...
Canada NC, Beard WL, Guyan ME, White BJ.Currently, there is no objective information quantifying pressures exerted by distal limb bandages. Objective: To quantify the pressure exerted by each compression layer, a polo wrap (DLP), a compression bandage (DLC), and to measure the effect of time on sub-bandage pressure. Methods: Longitudinal observational experiment. Methods: A DLC construct included a cotton roll compressed with brown gauze and elastic layers and the DLP construct included a pillow pad compressed by a cloth wrap. Dorsal and lateral sensors were placed on the mid-metacarpus. In healthy horses, sub-bandage pressures were...
Lulla V, Lulla A, Wernike K, Aebischer A, Beer M, Roy P.African horse sickness virus (AHSV), an orbivirus in the Reoviridae family with nine different serotypes, causes devastating disease in equids. The virion particle is composed of seven proteins organized in three concentric layers, an outer layer made of VP2 and VP5, a middle layer made of VP7, and inner layer made of VP3 that encloses a replicase complex of VP1, VP4, and VP6 and a genome of 10 double-stranded RNA segments. In this study, we sought to develop highly efficacious candidate vaccines against all AHSV serotypes, taking into account not only immunogenic and safety properties but als...
Falvo D'Urso Labate G, Baino F, Terzini M, Audenino A, Vitale-Brovarone C, Segers P, Quarto R, Catapano G.One of the hardest tasks in developing or selecting grafts for bone substitution surgery or tissue engineering is to match the structural and mechanical properties of tissue at the recipient site, because of the large variability of tissue properties with anatomical site, sex, age and health conditions of the patient undergoing implantation. We investigated the feasibility of defining a quantitative bone structural similarity score based on differences in the structural properties of synthetic grafts and bone tissue. Methods: Two biocompatible hydroxyapatite porous scaffolds with different nom...
Singh S, Chopra M, Dilbaghi N, Manuja BK, Kumar S, Kumar R, Rathore NS, Yadav SC, Manuja A.Isometamidium hydrochloride (ISMM) is an effective drug for the treatment of trypanosomosis, but it causes local and systemic toxicity. Isometamidium hydrochloride has limited therapeutic index and exhibit considerable variation in their prophylactic activities. We developed a trypanocidal nanoformulation using ISMM and polymers sodium alginate/gum acacia to enhance the efficacy of the drug at lower doses, while minimizing undesirable side effects. It was characterized by transmission electron microscopy and infrared spectroscopy for evaluation of size, morphology, functional groups, etc. In v...
Nout-Lomas YS, Page KM, Kang HG, Aanstoos ME, Greene HM.There is poor agreement between observers of equine neurological gait abnormalities using the modified Mayhew grading scale. Objective: To stimulate a dose-dependent ataxia in horses through xylazine administration and identify quantifiable relevant gait parameters. Methods: Balanced, randomised, 2-way crossover design. Methods: Eight horses were assessed before and after administration of xylazine (low dose and high dose). Gait analyses performed before and after xylazine administration included: 1) kinematic data collected on an equine high-speed treadmill (flat and 10% decline) and from acc...
Decloedt AI, Bailly-Chouriberry L, Vanden Bussche J, Garcia P, Popot MA, Bonnaire Y, Vanhaecke L.To ensure fair competition and to protect the horse's welfare, horses have to compete on their own merits, without any unfair advantage that might follow the use of drugs. Therefore, regulatory authorities list all substances that are not allowed in competition, including most anabolic-androgenic steroids. As zero-tolerance is retained, the question arose whether the consumption of mouldy feed could lead to the excretion of steroids, due to the biotransformation of plant phytosterols to steroids. A rapid ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analyt...
Kader A, Liu X, Dong K, Song S, Pan J, Yang M, Chen X, He X, Jiang L, Ma Y.Copy number variation (CNV), an essential form of genetic variation, has been increasingly recognized as one promising genetic marker in the analysis of animal genomes. Here, we used the Equine 70K single nucleotide polymorphism genotyping array for the genome-wide detection of CNVs in 96 horses from three diverse Chinese breeds: Debao pony (DB), Mongolian horse (MG) and Yili horse (YL). A total of 287 CNVs were determined and merged into 122 CNV regions (CNVRs) ranging from 199 bp to 2344 kb in size and distributed in a heterogeneous manner on chromosomes. These CNVRs were integrated with s...
Veraa S, Bergmann W, van den Belt AJ, Wijnberg I, Back W.Diagnostic imaging is one of the pillars in the clinical workup of horses with clinical signs of cervical spinal disease. An improved awareness of morphologic variations in equine cervical vertebrae would be helpful for interpreting findings. The aim of this anatomic study was to describe CT variations in left-right symmetry and morphology of the cervical and cervicothoracic vertebrae in a sample of horses. Postmortem CT examinations of the cervical spine for horses without congenital growth disorders were prospectively and retrospectively recruited. A total of 78 horses (27 foals, 51 mature h...
Herbig LE, Köhler L, Eule JC.The aim was to describe the use of the DUB®-SkinScanner v3.9 (taberna pro medicum GmbH, Lueneburg, Germany) for the examination of the equine cornea. Methods: Using the DUB®-SkinScanner v3.9 various pathological corneal conditions were pictured in the A- and B-mode at a frequency of 22 and/or 50 MHz in nine eyes of eight horses. Scans were obtained from standing horses or from horses under general anesthesia non-related to image acquisition. Results: The examination allowed real time imaging and measurement of the equine cornea in vivo. Compared to slit-lamp biomicroscopy additional informa...
Mastellar SL, Coleman RJ, Urschel KL.Lysine has been reported as the first limiting amino acid in typical equine diets. Indicator amino acid oxidation (IAAO) has become the standard method for determining amino acid requirements in other species, but prior to this study, it has not been used to determine equine requirements. The aim of this study was to evaluate whole body protein synthesis and plasma and muscle amino acid concentrations in response to graded levels of lysine intake in yearling horses. Six Thoroughbred colts (358 ± 5 kg) were fed each of six treatment lysine intakes ranging from 76 to 136 mg/kg body weig...
Sevane N, Dunner S, Boado A, Cañon J.Equine osteochondrosis (OC) is a frequent developmental orthopaedic disease with high economic impact on the equine industry and may lead to premature retirement of the animal as a result of chronic pain and lameness. The genetic background of OC includes different genes affecting several locations; however, these genetic associations have been tested in only one or few populations, lacking the validation in others. The aim of this study was to identify the genetic determinants of OC in the Spanish Purebred horse breed. For that purpose, we used a candidate gene approach to study the associati...
Karme A, Rannikko J, Kallonen A, Clauss M, Fortelius M.Different diets wear teeth in different ways and generate distinguishable wear and microwear patterns that have long been the basis of palaeodiet reconstructions. Little experimental research has been performed to study them together. Here, we show that an artificial mechanical masticator, a chewing machine, occluding real horse teeth in continuous simulated chewing (of 100 000 chewing cycles) is capable of replicating microscopic wear features and gross wear on teeth that resemble wear in specimens collected from nature. Simulating pure attrition (chewing without food) and four plant material...
Mira J, Herman M, Zakia LS, Olivo G, Araujo JP, Borges AS, Oliveira-Filho JP.Aural plaques can be found on the inner surfaces of one or both ears of horses. Despite their low malignancy, these lesions can sometimes cause discomfort and sensitivity in horses, and a loss in commercial value due to their aesthetic effect. There has been a study describing the epidemiological features and the clinical prevalence of equine aural plaques in Brazil. Objective: To determine the clinical prevalence and selected associated factors of aural plaques. Methods: In the study, 891 horses were assessed for aural plaques. The sample group had a median age of 5 years and comprised both s...
Panagiotopoulou O, Rankin JW, Gatesy SM, Hutchinson JR.Horse racing is a multi-billion-dollar industry that has raised welfare concerns due to injured and euthanized animals. Whilst the cause of musculoskeletal injuries that lead to horse morbidity and mortality is multifactorial, pre-existing pathologies, increased speeds and substrate of the racecourse are likely contributors to foot disease. Horse hooves have the ability to naturally deform during locomotion and dissipate locomotor stresses, yet farriery approaches are utilised to increase performance and protect hooves from wear. Previous studies have assessed the effect of different shoe desi...
Creton B, Pageat P, Robejean M, Lafont-Lecuelle C, Cozzi A.Hematophagous insects can be vectors of pathogens and cause significant economic loss in zootechnical production. Among biting insects, many dipteran species feed on horse blood. The black fly (Diptera: Simuliidae) group, is responsible for several disorders in horses and inflicts painful bites that lead to undesirable behaviours in horses, particularly when bites occur in sensitive areas such as the inner ear. A field study was conducted in a French equestrian center during which a semiochemical was applied on horses' ears to assess repellent efficacy against simulid infestation. During the f...
Farah Z, Fan H, Liu Z, He JQ.Correct selection of an appropriate animal mode to closely mimic human extremity diseases or to exhibit desirable phenotypes of limb regeneration is the first critical step for all scientists in biomedical and regenerative researches. The commonly-used animals in limb regeneration and repairing studies, such as axolotl, mice, and rats, are discussed in the review and other models including cockroaches, dogs, and horses are also mentioned. The review weighs the general advantages, disadvantages, and precedent uses of each model in the context of limb and peripheral injury and subsequent regener...
Bottagisio M, Pellegata AF, Boschetti F, Ferroni M, Moretti M, Lovati AB.Tendon ruptures and/or large losses remain to be a great clinical challenge and often require full replacement of the damaged tissue. The use of auto- and allografts or engineered scaffolds is an established approach to restore severe tendon injuries. However, these grafts are commonly related to scarce biocompatibility, site morbidity, chronic inflammation and poor biomechanical properties. Recently, the decellularisation techniques of allo- or xenografts using specific detergents have been studied and have been found to generate biocompatible substitutes that resemble the native tissue. This...
Fischer EAJ, Martínez López EP, De Vos CJ, Faverjon C.Equine encephalosis is a midge-borne viral disease of equines caused by equine encephalosis virus (EEV, Orbivirus, Reoviridae), and closely related to African horse sickness virus (AHSV). EEV and AHSV share common vectors and show similar transmission patterns. Until now EEV has caused outbreaks in Africa and Israel. This study aimed to provide insight in the probability of an EEV outbreak in The Netherlands caused by infected vectors or hosts, the contribution of potential source areas (risk regions) to this probability, and the effectiveness of preventive measures (sanitary regimes). A stoch...
Hobbs SJ, Bertram JE, Clayton HM.Background. Although the trot is described as a diagonal gait, contacts of the diagonal pairs of hooves are not usually perfectly synchronized. Although subtle, the timing dissociation between contacts of each diagonal pair could have consequences on gait dynamics and provide insight into the functional strategies employed. This study explores the mechanical effects of different diagonal dissociation patterns when speed was matched between individuals and how these effects link to moderate, natural changes in trotting speed. We anticipate that hind-first diagonal dissociation at contact increa...
Pfau T, Daly K, Davison J, Bould A, Housby N, Weller R.Military working horses perform a high proportion of work on road surfaces and are shod frequently to deal with high attrition rates. The authors investigate the influence of shoeing on movement symmetry as an indirect indicator of mechanical differences affecting force production between contralateral limbs. In this quantitative observational study, inertial sensor gait analysis was performed in 23 Irish sport type horses (4-21 years, 1.58-1.85 m) in full ceremonial work at the King's Troop, Royal Horse Artillery. Changes in two movement symmetry measures (SI: symmetry index; MinDiff: dif...
Lemieux H, Boemer F, van Galen G, Serteyn D, Amory H, Baise E, Cassart D, van Loon G, Marcillaud-Pitel C, Votion DM.Equine atypical myopathy in Europe is a fatal rhabdomyolysis syndrome that results from the ingestion of hypoglycin A contained in seeds and seedlings of Acer pseudoplatanus (sycamore maple). Acylcarnitine concentrations in serum and muscle OXPHOS capacity were determined in 15 atypical myopathy cases. All but one acylcarnitine were out of reference range and mitochondrial respiratory capacity was severely decreased up to 49% as compared to 10 healthy controls. The hallmark of atypical myopathy thus consists of a severe alteration in the energy metabolism including a severe impairment in muscl...
Han H, Mao C, Chen N, Lan X, Chen H, Lei C, Dang R.Kit gene is a genetic determinant of horse white coat color which has been a highly valued trait in horses for at least 2,000 years. Single nucleotide polymorphisms (SNPs) in Kit are of importance due to their strong associations with melanoblast survival during embryonic development. In this study, a mutation analysis of all 21 Kit exons in 14 Chinese domestic horse breeds revealed six SNPs (g.91214T>G, g.143245T>G, g.164297C>T, g.170189C>T, g.171356C>G, and g.171471G>A), which located in 5'-UTR region, intron 6, exon 15, exon 20, intron 20, and exon 21 of the equine Kit gene, respectively. S...
Ricard A, Blouin C.The longevity of sport horses is an economic and ethical issue. The aim of this study was to analyze the duration of the competitive life of jumping horses in France to assess the potential for genetic evaluation and to propose rules of management for sport horses. Data included lifetimes spent in jumping competitions for the 209,296 horses born from 1968 onward with performances between 1972 and 2008; the data set contained 22% right-censored records. Longevity was measured in years. Discrete survival analysis included fixed effects of region of birth, month of birth, year of recording, age a...
Young LE.Our recent data have confirmed that maximum oxygen delivery in racing Thoroughbreds is positively correlated to left ventricular mass measured by echocardiography. A similar, but weaker relationship also exists between left ventricular mass and Timeform performance rating in commercial racehorses. The relationship of the Thoroughbred heart to racing success and the special problems that selective breeding for aerobic capacity have had in this species are reviewed in this article.
Epperly E, Whitty JA.Computed tomography (CT) has revolutionized the veterinarian's ability to image the equine skull and led to improved diagnostic accuracy and clarity for surgical planning. The increased cost for this evaluation is offset by more accurate diagnosis and targeted therapy. As novel technology is developed that allows for increased availability of equine head, the price will continue to decrease and more examinations will be performed. New skills are needed for the veterinarian to accurately interpret this modality. This article reviews the normal CT appearance of the equine skull and presents exam...
Górniak W, Wieliczko M, Soroko M, Korczyński M.Methods of estimating horse body weight using mathematical formulae have better accuracy than methods of reading body weight from measuring tape. The aim of the study was to evaluate established formulae for estimating horse body weight from data gathered using measurement tape. The research was conducted in a group of 299 adult horses and ponies of selected breeds: ponies ( = 58), Polish Noble Half Breed ( = 150), Silesian Breed ( = 23), Wielkopolski Breed ( = 52), and Thoroughbred ( = 16). Body measurements were performed on each horse using a measuring stick and tape. The actual body weight...
Matthews N, van Loon JPAM.The number of donkeys in the world may not be increasing but awareness of their use and concern for welfare and pain recognition and treatment are receiving increasing veterinary interest. Therefore, accurate information about anesthesia and analgesia in donkeys and mules is important to more equine practitioners. This review highlights the current knowledge on various anesthetic and analgesic approaches in donkey and mules. The authors emphasize that there is still much information that is not available about donkeys and mules; in many circumstances, the clinician must use available equine in...
Gleeson LJ, Studdert MJ.Intrauterine infection of pregnant mare with equine herpesvirus type 2 (EHV 2) did not result in foetal abortion, stillbirth or recognisable disease. Collection of uterine fluid by allantocentesis or amniocentesis 107 days after inoculation confirmed that intrauterine infection was established. EHV 2 was isolated from both allantoic and amniotic fluid separately collected at the time of elective Caesarean section 156 days after inoculation and virus neutralising antibody to EHV 2 was present in the foal's presuckle serum at birth. A very mild clinical disease, characterised by a scant, mucous ...
Love CC, Noble JK, Standridge SA, Bearden CT, Blanchard TL, Varner DD, Cavinder CA.The relationship between the quality of cool-shipped stallion semen and fertility has not been adequately described. This study evaluated sperm quality of cool-shipped semen from 459 ejaculates (N = 130 stallions) that were used for insemination of 196 embryo donor mares (n = 496 estrous cycles). Embryo recovery rate (ERR; %) increased, as all sperm measures (e.g., motility, viability, DNA quality, morphology, concentration, and total number) increased. Threshold values are reported for each sperm quality measure (e.g., total sperm motility ≥ 65%) that separate two ERR groups (e.g., av...
Hintze S, Roth E, Bachmann I, Würbel H.Judgment bias tasks for nonhuman animals are promising tools to assess emotional valence as a measure of animal welfare. In view of establishing a valid judgment bias task for horses, the present study aimed to evaluate 2 versions (go/no-go and active choice) of an auditory judgment bias task for horses in terms of acquisition learning and discrimination of ambiguous cues. Five mares and 5 stallions were randomly assigned to the 2 designs and trained for 10 trials per day to acquire different operant responses to a low-frequency tone and a high-frequency tone, respectively. Following acquisiti...
Cheal EJ, Snyder BD, Nunamaker DM, Hayes WC.The objective of this investigation was to examine the stress-morphology relationships for trabecular bone around implants with different surface characteristics. Stainless steel spheres with either a polished surface or a sintered-bead porous coating were implanted unilaterally into equine patellae and maintained for a 6 month period. Stereological methods were used to quantify the trabecular bone morphology and finite element analyses were performed to predict the trabecular bone stresses. In general, the remodeling response around the smooth implants was greater than that around those porou...
Haussler KK.Manual therapies involve the application of the hands to the body, with a diagnostic or therapeutic intent. Touch therapies, massage, joint mobilization, and manipulation are all critical components in the management of muscular, articular, and neurologic components of select injuries in performance horses. Musculoskeletal conditions that are chronic or recurring, not readily diagnosed, or are not responding to conventional veterinary care may be indicators that manual therapy evaluation and treatment is needed.
Consuegra C, Crespo F, Bottrel M, Ortiz I, Dorado J, Diaz-Jimenez M, Pereira B, Hidalgo M.The aim of this study was to assess different concentrations of sucrose-based extenders combined with bovine serum albumin (BSA) as an alternative to stallion sperm cryopreservation with permeable cryoprotectants. Semen samples (n = 16) were collected from six stallions. Sperm was cooled, filled in 0.5 mL straws and frozen in nitrogen vapor. Post-thaw sperm kinetic parameters, plasma and acrosome membrane integrity were statistically compared among treatments. In Experiment 1, extenders containing 1% of BSA and different concentrations of sucrose (mmol/L, M): 0, 50, 100, 250, 350 and 450...
Matera MG, Amorena M, Lucisano A.Equine obstructive pulmonary disease (COPD), or heaves or recurrent airway obstruction, is a common equine pulmonary disease similar to human asthma and/or CODP. Since bronchospasm and inflammation are the key features in heaves, the purpose of this paper is to review the contribution of neural mechanism that may be relevant to this disease. Equine airway receive cholinergic and adrenergic innervation, as well as observed in many species. It was suggested that the autonomic neural control in asthma might be defective with an imbalance between excitatory and inhibitory pathways, resulting in ex...
Choi YH, Ritthaler J, Hinrichs K.Cloned animals possess mitochondria derived from the host ooplast, which typically differ genetically from those of the donor. This is of special concern to horse breeders, as maternal lines are prized and athletic performance is a key factor in genetic value. To evaluate the feasibility of producing mitochondrial-identical cloned foals, we collected oocytes from immature follicles of two mares, BL and SM, maternally related to the donor stallion. In vitro matured, enucleated oocytes were treated with roscovitine-synchronized donor cells and blastocysts were transferred transcervically to reci...
Rankins EM, McKeever KH, Malinowski K.Equid welfare in equine assisted services (EAS) is an area that has received attention, but less attention than the documentation of human outcomes in response to EAS. To safeguard the well-being of equids and minimize human risk of injury, continued research on the effects of EAS programming and participants on equids needs to occur. The aims of this systematic scoping review were to identify the approaches taken for describing and understanding equids in EAS and the methods employed in evaluating equids' responses to EAS programming, participants, or both. Literature searches were performed ...
Plant DR, Kearns CF, McKeever KH, Lynch GS.Clenbuterol is a beta2-adrenoceptor agonist primarily used for treating bronchospasm and alleviating the symptoms of chronic obstructive pulmonary disease (COPD) in the horse. In other species (rats, mice, sheep, and cattle), chronic high doses of clenbuterol (typically in the milligram per kilogram body weight range) has been shown to cause a muscle directed protein anabolic response. Clenbuterol can also modify muscle fibre composition and therefore potentially affect muscle function. This has implications for the performance of exercising horses being treated with therapeutic doses of clenb...
Fan F, Plapp BV.The contributions of isoleucine residues 224 and 269 of horse liver alcohol dehydrogenase to binding of the adenine moiety of NAD and to catalysis were studied by replacing Ile-224 with glycine (I224G) and Ile-269 with serine (I269S). The kinetic mechanisms of wild-type and both mutated liver enzymes were ordered. Affinities for several adenosine derivatives were decreased 5-50-fold by both substitutions. The I269S mutation differentially destabilized binding of the complete coenzyme, as affinities for NAD+ and NADH were decreased about 60-fold with the I224G enzyme and 350-fold for the I269S ...
Staszyk C, Gasse H.The distribution and arrangement of oxytalan fibres were examined in periodontal specimens of cheek teeth from seven horses. Oxidation prior to aldehyde fuchsin exposition permitted a selective staining of the oxytalan fibres, which are a distinct component of the elastic fibre system. On three horizontal levels of the periodontium--(a) subgingival, (b) middle third and (c) apical--two oxytalan fibre groups were shown histologically: 'blood vessel-related' and 'independent' oxytalan fibres. In levels a and b, both groups were arranged in a typical occluso-apical alignment along the reserve cro...
Mayhew IG, Washbourne JR.Magnetic stimulation of motor pathways was used to effect motor unit action potential recordings from forelimb and hindlimb muscles in unanesthetized ponies. Motor pathway conduction velocities to the forelimb and hindlimb were determined to be 53.8 +/- 9.6 m/s-1 and 63.4 +/- 8.3 m/s-1, respectively. This noninvasive technique will enable more precise evaluation of motor deficits in clinical patients than is possible with the neurological examination.
Vettorato E, Chase-Topping ME, Clutton RE.The recovery quality scoring systems (RQSSs) in current use have not been critically reviewed for reliability. Objective: To examine reliability (reproducibility) of 4 RQSSs when applied to a ranked series. Methods: A DVD incorporating the recordings of 9 horses recovering from general anaesthesia was evaluated by final year students over 5 days. On Day 1, each evaluator ranked recoveries from 1-9 (1 = best). Over the following 4 days, each evaluator scored the same recoveries using 4 different RQSSs (3 of them in common usage and previously published) applied in random order. The scores from ...
Irvine CH, Alexander SL.Conflicting views exist on the mode of gonadotrophin-releasing hormone (GnRH) secretion during the ovulatory LH surge and the relative importance of changes in pituitary responsiveness to GnRH in generating the LH surge. This disagreement may stem from species differences and/or methodological problems. To provide data on the exact relationship between GnRH and gonadotrophin secretion during the spontaneous LH surge, we collected pituitary venous (PV) blood every 30 s for 3-4 h from eight mares and then assayed GnRH (in six of the mares), FSH and LH. Jugular blood was also collected from twelv...
Sells DM, Hildebrandt PK, Lewis GE, Nyindo MB, Ristic M.The ultrastructure of the etiological agent of equine ehrlichiosis, Ehrlichia equi, was studied in equine peripheral leukocytes. The organisms occurred within membrane-lined cytoplasmic vacuoles of neutrophils and eosinophils. Ovoid, round, and rod-shaped profiles were observed. From 1 to 33 organisms were present in a thin-section profile of a cytoplasmic vacuole. Many cells contained multiple organism-containing vacuoles. The organisms had a cell wall and plasma membrane, and internally they consisted of electron-dense and lucid areas. A great variation in size was observed. The morphologica...
Barakzai SZ, Dixon PM.Trephination of the equine sinuses is a common surgical procedure in sedated standing horses. Standing sinus flap surgery has become increasingly popular in equine referral hospitals and offers several advantages over sinusotomy performed under general anesthesia, including reduced patient-associated risks and costs; less intraoperative hemorrhage, allowing better visualization of the operative site; and allows surgeons to take their time. Other minimally invasive surgical procedures include sinoscopic surgery, balloon sinuplasty, and transnasal laser sinonasal fenestration. Despite the proced...
The Journal of physiologyNovember 15, 1996
Volume 497 ( Pt 1), Issue Pt 1 19-29 doi: 10.1113/jphysiol.1996.sp021746
Ko WH, Chan HC, Wong PY.1. Anion secretion induced by capacitative Ca2+ entry through apical and basolateral membranes of cultured equine sweat gland epithelium was studied using the short-circuit current (Isc) technique. 2. Thapsigargin induced an increase in Isc that could be inhibited when external Ca2+ was chelated by EGTA. 3. The inhibition of the thapsigargin-induced Isc could be reversed by re-addition of Ca2+ to apical or basolateral solutions. The magnitude of the reactivated Isc depended predominantly on basolateral Ca2+ concentration. 4. The magnitude of the reactivated Isc upon basolateral Ca2+ addition i...