"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.
Kristinsson J, Thordarson TH, Johannesson T.The pharmacokinetics of lignocaine was studied in four Icelandic horses after infiltration anaesthesia. A total of 240 mg of the drug was injected on either side of the left foreleg, over the medial and lateral branches of the palmar nerve. Blood samples were collected up to seven hours after injection and the concentrations of the drug in plasma were determined by gas chromatography/mass spectrometry. The results showed that lignocaine was rapidly absorbed. A mean maximum concentration of 232 ng/ml was observed after 20 minutes. In three of the horses the decline in the plasma concentration o...
Bell BT, Bridge IS, Sullivan ST.Seventeen horses diagnosed as having navicular syndrome on the basis of history, clinical findings, regional local anaesthesia and radiography were subjected to bilateral navicular suspensory desmotomy. Before surgery, the duration of navicular lameness ranged from 6 weeks to 4 years. Previous unsuccessful treatments prior to surgery included nonsteroidal anti-inflammatories, corrective shoeing, rest and isoxsuprine. For the seventeen horses subject to surgery, twelve horses were sound, one horse was improved and four horses were lame at a minimum of 6 months after surgery.
Mayhew TM, Mwamengele GL, Dantzer V, Williams S.Describing the shapes of 3D objects has proved to be as problematical in biology as in other areas. In an attempt to tackle this problem, established stereological methods (the Cavalieri principle and vertical sectioning) have been used to estimate a 3D shape-dependent quantity which can detect anisomorphic changes and is related to the degree of cortical convolution or gyrification. This isomophy factor is employed to assess phylogenetic and ontogenetic changes in the mammalian cerebral cortex. Gross anatomical differences between cerebral hemispheres of adult domestic mammals (horses, oxen, ...
Dell'aquila ME, Fusco S, Lacalandra GM, Maritato F.The aim of this study was to develope an efficient and reproducible procedure for in vitro maturation (IVM) and fertilization (IVF) in the horse. Cumulus-oocyte complexes (COCs) recovered from the ovaries of mares slaughtered during the breeding season were morphologically evaluated, and those showing a compact cumulus and homogeneously appearing cytoplasm were selected for culture. Effects on the maturation of estrous mare serum (EMS) versus estrous cow serum (ECS) as medium supplement were also evaluated (Experiment 1). In Experiment 2, the fertilization of in vitro matured oocytes with froz...
Nouri-Sorkhabi MH, Agar NS, Sullivan DR, Gallagher C, Kuchel PW.The phospholipid classes of erythrocyte membranes and plasma from several domestic animals and marsupials were quantified by 31P NMR using detergents. Washed erythrocyte samples were thoroughly haemolysed by tip-sonication and dissolved in sodium cholate; plasma samples were dissolved in Triton X-100. The species studied were: common wombat (Vombatus ursinus), black-striped wallaby (Macropus dorsalis), bandicoot (Isoodon macrocarpus), Eastern grey kangaroo (Macropus giganteus), Tammar wallaby (Macropus eugenii), sheep (Ovis aries), goat (Capra hircus), cattle (Bos taurus), horse (Equus caballu...
Guthrie AJ, Short CR, Swan GE, Mülders MS, Killeen VM, Nurton JP.This paper describes the use of subcutaneously-placed tissue chambers as a sterile soft-tissue inflammation model in Thoroughbred horses. Acute, non-immune inflammation was initiated by injecting a sterile lambda carrageenan solution into a tissue chamber. This model was used to study the temporal changes in oxygen and carbon dioxide tensions, pH, bicarbonate, protein, albumin, prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) concentrations, cell counts and differential counts in tissue fluid from inflamed tissue chambers and control chambers. Skin temperatures over control and inflamed chamb...
Chopineau M, Stewart F.Reverse transcription-PCR was used to clone the coding region of the donkey (Equus asinus) glycoprotein hormone alpha-subunit transcript from pituitary gland RNA. The donkey alpha-subunit sequence demonstrated considerable identity with the horse (97% at the nucleotide level), confirming the very close evolutionary linkage between these two species. The predicted amino acid sequence revealed that the donkey alpha-subunit has the same unusual C-terminus as the horse alpha-subunit, when compared with all other mammalian alpha-subunits, including a Tyr-His transposition between positions 87 and 9...
Lowden S, Heath T.In the horse ileum, lacteals in the villi are continuous with prelymphatic intercellular channels and a plexus of lymphatic sinuses in the lamina propria that encircle the domes of the follicle/dome structures and proprial follicles. These sinuses may act as the major entry site for many of the lymphocytes migrating from gut-associated lymphoid tissue via the lymphatic system. Vessels from this plexus penetrate the muscularis mucosae and lymph flows into lymphatic vessels within the interfollicular tissue between the follicles of both follicle/dome structures and lymphoglandular complexes (LGC...
Proudman CJ, Trees AJ.Whole worm extract (WWE) and excretory/secretory (E/S) antigens of Anoplocephala perfoliata were characterised by SDS-PAGE and their use in the serodiagnosis of equine cestodosis was evaluated. An enzyme-linked immunosorbent assay (ELISA) was used to compare WWE and E/S antigen as the capture layer in an antibody capture ELISA. E/S antigen gave the best differentiation between sera from tapeworm-positive and tapeworm-negative horses. The E/S-ELISA was optimised and validated against sera from horses of known tapeworm status. This assay gave a diagnostic sensitivity of 68% (n = 38) and a specif...
Bolin CA, Zuerner RL.Isolates (n = 147) of Leptospira interrogans serovar pomona type kennewicki from cattle, swine, horses, and wildlife were analyzed by DNA restriction endonuclease analysis. Restriction fragment length polymorphisms were identified in DNA digested with HpaII, and the restriction fragment length polymorphisms were correlated with the host animal source of the isolates. These results will be useful in understanding the epidemiology of serovar pomona infections in livestock.
Rapp HJ, Weinreuter S.Etiology, diagnosis and therapy of the luxation of the shoulder joint in the horse are described. The traumatic luxation is diagnosed by physical examination and radiography. Without complicating changings (like fractures) and in case of early correction the prognosis is good.
Lillich JD, Bertone AL, Schmall LM, Ruggles AJ, Sams RA.OBJECTIVE--To document plasma, urine, and synovial fluid disposition of 2 common intra-articularly administered steroid preparations, methylprednisolone acetate (MPA) and isoflupredone acetate (IPA). DESIGN--Descriptive investigation. SAMPLE POPULATION--100 mg of MPA or 4 mg of IPA was administered to 2 groups of 4 healthy sound radiographically normal female horses. PROCEDURE--Blood samples were collected at time 0 (before) and 2, 4, 6, 8, 10, 12, 24, 36, 48, 72, and 96 hours after administration of the designated steroid. Complete urine collection for measurement of designated steroid was ac...
Soraci AL, Mestorino ON, Errecalde JO.The pharmacokinetics and bioavailability of cefoperazone (CPZ) were studied following intravenous (IV) and intramuscular (IM) administration of single doses (30 mg/kg) to horses. Concentrations in serum, urine and synovial fluid samples were measured following IV administration. CPZ concentrations in serum, synovial fluid and spongy bone samples were measured following IM administration. After IV administration a rapid distribution phase (t1/2 (alpha): 4.22 +/- 2.73 min) was followed by a slower elimination phase (t1/2(beta) 0.77 +/- 0.19 h). The apparent volume of distribution was 0.68 +/- 0....
Matsumura T, O'Callaghan DJ, Kondo T, Kamada M.The virulence of the cell culture adapted KyA strain of equine herpesvirus type 1 (EHV-1), which lacks at least six genes by deletions in its genome, was assessed by intranasal inoculation of six young horses that were serologically negative for EHV-1. No horses showed clinical signs, and a neutralizing antibody response against EHV-1 was detected in two horses which had antibodies against EHV-4 prior to the inoculation. A challenge experiment using a highly virulent strain of EHV-1 conducted 4 weeks later against 4 of the 6 horses inoculated intranasally with the KyA strain and 2 control hors...
Skarda RT, Muir WW.To examine effects of 0.25 mg of xylazine/kg of body weight diluted to a total volume of 6 ml/450 kg with sterile 0.9% NaCl, administered into the epidural space of the sacrococcygeal joint on perineal analgesia, sedation, ataxia, and respiratory and cardiovascular function in standing mares. Methods: Randomized, blinded study, using xylazine (treatment) and 0.9% NaCl (controls). At least 2 weeks elapsed between the treatments. Methods: Eight healthy mares. Methods: Blood samples were drawn. Systemic hemodynamics were determined, including cardiac output and pulmonary arterial, systemic arteri...
Ito A, Imai S, Ogimoto K, Nakahara M.The composition of intestinal ciliates excreted in the feces of 20 Tokara native ponies kept in Iriki farm of Kagoshima University was surveyed. Eleven genera consisting of 18 species were identified based on the description of Strelkow. One new genus including a new species, Wolskana tokarensis n. gen., n. sp., of the family Buetschliidae was recognized and described. The average ciliate density of all horses was 13.8 x 10(3)/ml. Those of stallions (n = 5), mares (n = 11) and foals (n = 4) were 3.9, 16.1 and 43.3 x 10(3)/ml respectively. The value of stallions was significantly lower and that...
Chen CL, Zhu D, Gillis KD, Meleka-Boules M.To develop a simple and sensitive ELISA for detection of dexamethasone in horse serum and urine. Methods: Blood and urine samples from 3 thoroughbred mares. Methods: A dexamethasone oxime was prepared and conjugated to hemocyanin, bovine serum albumin and to horseradish peroxidase. One- and two-step double-antibody ELISA methods, as well as a radioimmunoassay method, were performed. The one-step ELISA was used to test urine from 3 Thoroughbred mares injected with 5 mg of dexamethasone, IV. Results: The ELISA could detect dexamethasone in the range of 0.01 to 50 ng/ml, with intra- and interassa...
Stocker H, Kaser-Hotz B, Lischer C, Zahn I, Ehrensperger F.A three-week-old foal was submitted to the clinic because of a minor traumatic injury at the lower jaw. At admission the foal exhibited diarrhea, a distended abdomen and reduced general condition. These findings could not be associated with the injury. On abdominal radiography decreased abdominal detail and a dorsocaudal displacement of the intestine was present. Ultrasonographically multiple fluid-filled cystic structures of several centimeters in diameter were identified. These cystic structures appeared to be associated with the liver. At laparotomy and at necropsy the liver was markedly en...
Raidal SL, Love DN, Bailey GD.Tracheal mucociliary clearance was determined in horses by measuring the rostrad transport of the radiopharmaceutical 99mtechnetium-sulphur colloid following deposition on the tracheal epithelium by intratracheal injection. The effects of head position (head elevated to normal standing position vs head lowered) and of accumulated purulent secretions on tracheal mucociliary clearance were evaluated for the first time in the horse. In normal horses tracheal mucociliary clearance was greatly accelerated by lowering the head so that the cranial trachea was lower than the caudal trachea. Horses con...
Kuwabara M, Inukai N, Inanami O, Miyake YI, Tsunoda N, Maki Y, Sato F.Hotbred (Thoroughbred) horses were grouped into three classes according to the levels of constant physical exercise (foals, 6 months old; racing horses, 5 years old; horses for breeding, 6-10 years old), and lipid peroxide levels in their sera were measured as thiobarbituric acid-reactive substances. No significant differences were observed among them. The superoxide-scavenging abilities of sera were measured next; to examine the antioxidative properties of hotbreds, and were found to be highest in the racing horses. The higher scavenging ability of the racing horses might contribute to keep t...
Williams D, Siock P, Stenn K.A major challenge to the study of hair follicle growth is an appropriate assay system. Because equine mane follicles are large and noncurved, enabling easy dissection; are readily accessible from a single defined source; and possess a long anagen growth phase, we initiated a study of them in culture. As in our previous studies of human and sheep follicles (Dev Biol 165:469, 1994), we found in this system that transection level dictates the pattern of follicle growth in vitro: follicles transected below the sebaceous gland show a type 1 growth pattern (the shaft grows out with an adherent sheat...
Pullin JG, Collier MA, Das P, Smith RL, DeBault LE, Johnson LL, Walls RC.Comparison of perilesional cartilage, lesional repair tissue, and subchondral bone activity 6 months after application of holmium-yttrium-aluminum-garnet (Ho:YAG) laser energy to chronic (10 week) induced 10-mm full-thickness (FT) circular articular cartilage craters followed by 6 months' intermittent active motion (IAM) in a free exercise environment was investigated. The 2.1-microns wavelength was delivered in hand-controlled near-contact mode by arthroscopic surgery in a saline medium. Bilateral arthroscopy was performed on normal antebrachiocarpal, intercarpal, and metacarpophalangeal join...
Beelitz P, Göbel E, Gothe R.In this epidemiological study 37 foals and mares were included, which have been coproscopically examined in regular intervals over a period lasting up to 13 months. The animals derived from nine breeding farms. In three of these farms no anthelmintics were used before this investigation, whereas in six farms at least three years before regular prophylactic treatments with anthelmintics have been carried out. This investigation revealed no differences in the species spectrum of endoparasites as well as in the incidence of infections as regards to the breeding farms with and without anthelmintic...
Sleeper MM, Palmer JE.The clinical and echocardiographic findings in a 19-h-old female foal with a ventricular septal defect, patent foramen ovale, patent ductus arteriosus, and complete transpositon of the great vessels are described. Clinical signs were suggestive of complex congenital heart disease and echocardiography of the foal allowed definitive diagnosis prior to postmortem.
Wells PW, McBeath DG, Eyre P, Hanna CJ.This article attempts to relate some of the more recently accepted concepts of immunology to an understanding of the mechanisms of immunity in the horse. The cellular mechanisms involved in the immune response are outlined, with an indication of their likely role in humoral and cell-mediated immunity. In describing the humoral immune response, the structure and function of the different equine immunoglobulins are reviewed. The significance of humoral and cell-mediated immune responses are considered in relation to actively and passively acquired immunity.
Młodawska W, Palmer E, Duchamp G, Okólski A, Bézard J.The binding of a spermatozoon to the zona pellucida is the first step in fertilization. The number of spermatozoa bound to a zona pellucida may reflect the functional status of both the oocyte and spermatozoa. The aim of the present study was to determine whether the stage of maturation of the equine oocyte affects the capacity of the zona pellucida to bind with spermatozoa. Cumulus-oocyte complexes (COCs) were collected from the ovaries of mares from abattoirs or were obtained in vivo by ultrasound-guided follicular aspiration. Oocytes were inseminated directly after collection or after 30 h ...
Drudge JH, Lyons ET, Tolliver SC, Fallon EH.Clinical trials on a central Kentucky Thoroughbred Farm (B) during 1960-1961 involved nine test treatments of mares, yearlings and weanlings (n = 124), and compared efficacies of phenothiazine (PTZ), piperazine (PPZ), mixtures of PTZ + PPZ and thiabendazole (TBZ) for (1) percent reduction and (2) complete clearance or graded reduction of strongyle egg per gram (epg) counts. Three grades of PTZ (N.F. green, micronized purified and 2-3 microns purified) at the dose rate of 55 mg kg-1 were ineffective in six tests; reduction of strongyle epg count were low grade (26%) and complete clearance was f...
Dik KJ, Boroffka S, Stolk P.Ultrasonography was used with 6 normal cadaver forelimbs of Dutch Warmblood horses to delineate the ultrasonographic anatomy of the palmar pastern region, with emphasis on the proximal digital annular ligament. Using a 5.5 MHz sector scanner, the thin proximal digital annular ligament was not visible on offset sonograms. Only if the digital sheath in the normal limb was distended was the distal border of this ligament outlined. In all normal limbs the palmarodistal thickness of the combined skin-proximal digital annular ligament layer in the mid-pastern region was 2 mm. The flexor tendons and ...
Frankland AL, Morris PG, Spreull JS.Seven pieces of autologous skin were transplanted onto freshly created, full thickness skin defects on the limbs and back of a one-year-old, male, piebald, Shetland pony. The transplantations were completed in two operative sessions, the transplants on the left side were done in the first session and the right side in the second. The sizes of the transplants varied from 20 sq cm to 2 sq cm and their thicknesses from whole skin to very thin, split skin. Donor sites were both rumps and the right side of the neck. Six of the seven grafts and two thirds of the remaining graft, were accepted. Both ...
Behrens NE, Gershwin LJ.Hypersensitivity reactions, such as hives or fatal anaphylactic shock, in response to vaccination constitute a health hazard for horses that develop allergies to vaccine components. In such horses vaccination with viral vaccines stimulates an IgE response to non-target antigens. Viral vaccines share contaminating non-target proteins, such as bovine serum albumin (BSA); these antigens can stimulate IgE production with each exposure. We hypothesized that the addition of a CpG oligodeoxynucleotide (ODN) administered in conjunction with a West Nile virus vaccine would decrease the IgE response; th...
Willis P, Sekhar KN, Brooks P, Fayrer-Hosken RA.To characterize further the events involved in fertilization and early embryonic development in the mare, effect of the estrous cycle on oviductal fluid proteins was investigated. Five mares had indwelling cannulas placed in their oviducts so that fluid could be collected throughout the estrous cycle. Daily fluid volumes were recorded and mares were monitored for signs of standing estrus. Oviductal fluid samples were pooled across mares according to stage of cycle (either estrus or nonestrus) for further analysis. Two-dimensional polyacrylamide gel electrophoresis (PAGE) was used to determine ...
Brown MP, Stover SM, Kelly RH, Farver TB.Ten healthy adult mares were given a single intramuscular dose (2.2 mg/kg) of gentamicin sulfate. Over a 48-h period, gentamicin concentrations were measured serially in the serum of all ten mares and in synovial fluid, peritoneal fluid, and urine of six of the mares. The mean peak serum gentamicin concentration was 5.73 micrograms/ml at 1 h. Gentamicin was detected in synovial fluid and peritoneal fluid, with mean peak gentamicin concentrations of 2.41 micrograms/ml and 3.92 micrograms/ml, respectively, observed at 2 h. These concentrations declined in parallel with serum concentrations and w...
Kobrina Y, Isaksson H, Sinisaari M, Rieppo L, Brama PA, van Weeren R, Helminen HJ, Jurvelin JS, Saarakkala S.The collagen phase in bone is known to undergo major changes during growth and maturation. The objective of this study is to clarify whether Fourier transform infrared (FTIR) microspectroscopy, coupled with cluster analysis, can detect quantitative and qualitative changes in the collagen matrix of subchondral bone in horses during maturation and growth. Equine subchondral bone samples (n = 29) from the proximal joint surface of the first phalanx are prepared from two sites subjected to different loading conditions. Three age groups are studied: newborn (0 days old), immature (5 to 11 months ol...
Deacon LJ, Reef VB, Leduc L, de Solis CN.This pictorial essay aims to display the image quality of pocket-sized ultrasound devices and hospital-based equipment to provide clinicians visual information about the potential uses of point-of-care ultrasonography (POCUS) in equine practice. Twenty-two paired images were obtained using traditional ultrasound equipment and pocket-sized ultrasound devices from patients evaluated at veterinary teaching hospitals. Images of many common ultrasound windows and miscellaneous sonographic abnormalities were obtained using pocket-sized ultrasound equipment.
Grabner A, Kraft W, Essich G, Hänichen T.Cases of enzootic calcinosis in breeding mares in a Southwest German highland area are reported. The symptoms increased in the latter part of summer and existed in disturbances of movement, moderate kyphosis, sensitivity to palpation in the flexor tendons and, especially, the suspensory ligament, weight loss in spite of good food intake during summer-time and painful costal percussion; less clinical signs of renal and cardiac disorders were established. The sickness was caused by a high percentage of Trisetum flavescens in the feeding plants.
Brainard BM, Epstein KL, LoBato DN, Kwon S, Darien BJ, Hurley DJ, Moore JN.Inflammation-induced P-selectin (CD62P) expression on platelets and endothelial cells facilitates interactions among platelets and polymorphonuclear leukocytes (PMN), and can also promote coagulation. The effects of clopidogrel and aspirin (ASA) on equine platelet CD62P expression were investigated. Six horses were treated in a cross-over design with clopidogrel (2mg/kg PO q 24) or ASA (5mg/kg PO q 24h) for 5 days. Platelets collected at 24, 72, 96, 120, and 168 h after the initiation of therapy were stimulated using 0.1 μg/mL thrombin, followed by flow cytometric analysis using anti-CD41/61 ...
Niwa H, Higuchi T, Fujii S, Kinoshita Y, Uchida-Fujii E, Sueyoshi M, Nukada T, Ueno T.Equine proliferative enteropathy (EPE) is an equine infectious disease that can lead to severe weight loss and hyperplasia of the intestinal mucosa due to infection with Lawsonia intracellularis. In this study, we investigated the prevalence of EPE in a major Thoroughbred breeding area: Hidaka district, Hokkaido, Japan. Of the 252 symptomatic horses that we tested, 192 EPE cases (76.2%), including 8 fatal cases, were confirmed from April 2015 to March 2020 by etiological and/or serological investigation. Most of the EPE cases were observed in foals (88.5%), with fewer cases in yearlings (7.3%)...
Campbell MLH.This paper assesses whether cloning horses is ethical by reviewing ethical arguments against cloning of nonequine species and determining whether they apply to horses, analysing ethical arguments about horse cloning which do not apply to noncompetitive species and considering the ethical dilemmas faced by veterinarians involved in horse cloning. The author concludes that concerns about the health and welfare of cloned horses render the technique ethically problematic and that the onus is on those providing commercial equine cloning services to collate data and provide a stronger evidence base ...
Nanda BS, Getty R.The consistent presence of the caroticobasilar artery was observed and discussed in view of the anatomical normalities in the horse. The persistence of the above vessel was correlated with the developmental changes in the cranial and cerebral arteries.