"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.
Teilmann AM, Hansen JC.The content of cadmium and selenium in horse kidneys from Jutland , Denmark, in relation to age, local geographical variation and possible relationship between the two elements has been investigated. During the winter of 1982-1983 kidneys from 50 horses were sampled and analysed for cadmium and selenium. The cadmium content of the horse kidneys was recorded in connection with the age of the horses. The cadmium level increases until the animal has reached approximately 7 years of age. At this age the cadmium concentration levels off. A significant regional difference was shown. The cadmium cont...
Löscher W, Jaeschke G, Keller H.The pharmacokinetics of ascorbic acid were studied in 29 horses after intravenous (iv), subcutaneous, intramuscular (im) and oral administration. Following iv injection of 5 and 10 g ascorbic acid, respectively, a biphasic decline of ascorbic acid serum levels was found, indicating that the vitamin distributes in the body according to a two-compartment open model. The apparent volume of distribution (average value for Vd(ss) = 0.6 litre/kg) was approximately equivalent to the volume of total body water. The terminal half-life of the biexponential serum level-time curve (t1/2 beta) varied betwe...
Dolan M, Cargill C, Martin F, Davenport P, Franks D, Lightfoot J.A bacteriological and serological survey for evidence of contagious equine metritis (CEM) was made during the 1980 breeding season on 3 horse studs in South Australia with a history of previous infection. Swabs from the clitoral sinus and the cervix were cultured for Haemophilus equigenitalis and serum was screened for antibody using the complement fixation test (CFT) and the enzyme-linked immunosorbent assay (ELISA). The specificity of both tests was greater than 0.99 but the ELISA was more sensitive in detecting antibody in infected mares. On the evidence presented it was concluded that H. e...
Tranquilli WJ, Thurmon JC, Neff-Davis CA, Davis LE, Benson GJ, Hoffman W, Lock TF.Plasma glucose and serum insulin concentrations in Thoroughbreds administered xylazine hydrochloride (1.1 mg/kg; IV) and ketamine hydrochloride (2.2 mg/kg; IV) at dosages sufficient to induce short periods of recumbency and anesthesia were measured. Samples of blood were collected from 6 adult horses before, during, and after the anesthetic period. Plasma glucose (mg/dl) was significantly increased above control (-30 minute concentration) from 15 to 150 minutes after xylazine administration with the peak value occurring at 30 minutes. Serum insulin (microU/ml) was significantly decreased from ...
Weaver BM, Lunn CE, Staddon GE.Muscle perfusion was studied in conscious and anaesthetised horses by monitoring the clearance of a locally injected bolus of saline containing radioactive xenon (133Xe). The mean of all the measurements made from the brachiocephalicus and semimembranosus muscles in conscious subjects was 1.29 ml/min/100 g while in anaesthetised subjects it was 0.40 ml/min/100 g. The significance of these results is discussed in relation to the clinical occurrence of post anaesthetic myositis.
Flieger S, Sławomirski J, Boratyński Z, Jastrzebski M.Two medullae oblongatae of horses were cut into 15 microns cross-sections and stained according to the modified method of Nissel. The lateral motor nucleus lies in the lateral and median part of the ventral column of spinal cord grey matter. It adjoins medially nucleus motorius medialis of the spinal ventral column. Cells of this nucleus occur both along the whole lumbar and sacral segment of the spinal cord. In the lateral motor nucleus three cell groups are distinguished - median, basal and lateral. The latter is divided in some segments into subgroups - dorsal and ventral. Along the nucleus...
Combarnous Y, Guillou F, Martinat N, Cahoreau C.The LH and FSH activities of equine choriogonadotropin (eCG) have been compared in several species with those of the highly purified homologous pituitary gonadotropins. The molar FSH/LH activity ratio of eCG determined by RRA is 0.20 in the pig, 0.25 in the rat and 0 in the horse. These data demonstrate the LH monospecificity of eCG in its own species as it is the case for hCG. We have also shown that equine LH exhibited a FSH-activity similar to that of eCG in the pig and in the rat but not in the horse. In the female rat, the binding activity to FSH receptors and the in vitro FSH activity of...
Williams S, Scott P.Meal contaminated by Datura stramonium seeds at the rate of 0.5% by weight was fed to two horses. Both horses showed clinical signs of depression, anorexia, weight loss, rapi heart and respiration rates, mydriasis, polyuria, polydipsia and diarrhoea. Both recovered with treatment. Maize screenings contaminated by the seeds had been used in the manufacture of the meal.
Perryman LE, Wyatt CR, Magnuson NS.Neoplastic lymphocytes from a horse with lymphosarcoma and IgM deficiency were analyzed for ability to grow in culture; surface and cytoplasmic IgM; functional activity in blastogenesis, cytoxicity, and suppressor assays; and activities of six enzymes involved in purine and pyrimidine metabolism. The cells lacked surface and cytoplasmic IgM. They had elevated activity of adenosine deaminase and reduced activity of purine nucleoside phosphorylase. Neoplastic cells were nonresponsive in blastogenesis assay and did not kill allogeneic lymphocyte target cells or YAC-1 targets in a lectin-dependent...
Bailey M, Lloyd S, Martin SC, Soulsby EJ.Proliferation in vitro of peripheral blood lymphocytes both from horses infected with Strongylus vulgaris and from helminth-free ponies was observed in the presence of extracts of the fourth and fifth stage larvae and adults of S. vulgaris. In addition, S. vulgaris extracts induced transformation in cultures of peripheral blood lymphocytes from sheep and dogs and in mouse spleen cell cultures. Nylon wool non-adherent, T cell enriched fractions of lymphocytes from both mice and horses were stimulated by the S. vulgaris larval mitogen while no proliferation was observed in cultures containing ny...
Grabner A.Using a fibreoptic endoscope ("small gastroscope" with outside diameter of 9.3 mm) a simple and sparing inspection of the guttural pouch is performed. The flap-type tube cover is opened by means of medial leverage with a guidance probe shifted through the work duct of the endoscope. The same procedure is used in diagnostic specimen collection and therapeutical measures such as irrigations. Guttural pouch topography and pathological disorders are illustrated by endoscopic photography. The different diseases such as follicular hyperplasia, ascending pharyngeal catarrh, perforating abscesses of t...
Sławomirski J, Flieger S, Jastrzebski M, Boratyński Z.The studies carried out on 2 spinal cords of horses showed that cells of the medial motor nucleus (nucleus motorius medialis) are present in all neuromers of the lumbar and sacral segment of the spinal cord. It lies in the medial part of grey matter of the ventral column, neighbouring laterally and ventrally with cells of the lateral motor nucleus, whereas dorsally with cells of the nucleus of the ventral commissural horn. Along the nucleus numerous constrictions and intervals are found, which are connected with various numbers of nerve cells in particular cross-sections.
Bailey E, Henney PJ.The distribution of ELY-2 was compared to the distribution of blood group factors Aa, Ab, Ac, Ae, Ca, Da, Db, Dc, Dd, De, Df, Dh, Dk, Ka, Pa, Pb, X, Qa, Qc, Ua, and W in 2465 American Standardbred horses and to ELY-1 in 193 American Standardbred horses. The distribution patterns were different in each case. The segregation of ELY-2.1 and factors at the A, C, D, K, P, Q, U and T (W) blood group loci and at the ELA locus indicated that ELY-2.1 is not a product of any of those loci. No segregation data were available for the ELY-1 locus. Family studies indicated that the gene for ELY-2.1 is not s...
García-Sacristán A, Casanueva CR, Castilla C, Labadia A.The presence and types of alpha and beta adrenergic receptors in the urethra and prostate of the horse were studied in vitro using adrenergic agonist and antagonist drugs. The existence of these receptors was shown. This finding was based on the observation that the contractile action was mediated by adrenergic receptors of alpha-1 type, although in the prostate alpha-2 type receptors also participated. Relaxation in both tissues was controlled by receptors of the beta-2 type.
van Wuijckhuise-Sjouke LA.This report describes fatal obstruction of the small colon of three horses. The obstructions were caused by irregularly shaped enteroliths of which the centres contained a foreign body, namely a guy-rope, a piece of baling twine , and a fishing-line, respectively. The diagnosis was made by post-mortem examination.
Juneja RK, Andersson L, Sandberg K, Gahne B, Adalsteinsson S, Gunnarsson E.Two-dimensional agarose gel (pH 8.6)-horizontal polyacrylamide gel (pH 9.0) electrophoresis of horse serum proteins revealed genetic polymorphism of ceruloplasmin (Cp) and two unidentified serum proteins tentatively designated serum protein 1 (SP1) and serum protein 2 (SP2). Family data were consistent with the hypothesis that the observed Cp and SP1 phenotypes were each controlled by two codominant, autosomal alleles. The three common SP2 phenotypes were shown to be controlled by two codominant, autosomal alleles. Population data and limited family data indicated the occurrence of two additio...
Gosztonyi G, Ludwig H.The brains of eight horses that had suffered from natural Borna disease were examined with virologic, immunohistological, and electron-microscopic methods. All brains harbored infectious virus as shown by inoculation of experimental animals. Regional assessment of the infectivity exhibited the highest titers in the hippocampus and piriform cortex and the lowest in the cerebellum. Conventional histology yielded pathologic alterations very similar to those of the classical description of the disease. Immunohistology demonstrated the highest amounts of Borna disease virus-specific antigen in the ...
Thompson DL, Reville SI, Derrick DJ, Walker MP.Eight seasonally anestrous mares were administered intravaginal polyurethane sponges on December 15 and then weekly thereafter until February 1. Control mares received no sponges or genital contact. Sponge insertion caused an immediate surge in follicle-stimulating hormone (FSH) concentrations in jugular plasma in 50% of treated mares whereas no control mares had surges in FSH (P less than .05). The effect of treatment on luteinizing hormone (LH) concentrations was much less dramatic and only three treated mares appeared to have positive responses. Sponge-treated mares exhibited positive respo...
Schatzmann U, Girard P.The paper describes the problems of injection anaesthesia in the horse. Different commonly used methods, drugs and drug combinations are explained. Their actions and side-effects are compared and discussed.
DeBowes RM, Grant BD, Bagby GW, Gallina AM, Sande RD, Ratzlaff MH.A modified form of the Cloward technique for anterior cervical fusion in human beings was used in the application of different grafts for evaluation of their effectiveness in stabilizing equine cervical vertebrae. Results of bovine xenograft implants in 8 horses were compared with results of stainless steel baskets (SSB) packed with cancellous autogenous bone in 8 horses. Graft material was incorporated in all cases. Evidence of graft rejection was not present. Both forms of implants decreased the mobility of the intervertebral space in which they were implanted. A fibrous connective tissue un...
Cozzi B, Ferrandi B.The horse pineal gland has been investigated by morphological and histochemical methods. Particular care has been given to the cellular types, to the eventual presence of neurosecretory activity and to the nature of the pigments. Even in the horse pineal, it is possible to distinguish two populations of pinealocytes, morphologically but not histochemically distinct. A great number of pinealocytes are positive for the Masson- Hamperl reaction, and for Gomori- Bargmann 's chromic haematoxylin-phloxine and Gomori's paraldehyde-fuchsin. Along the connective septa, many brown- blackish pigmented ce...
Firth EC, Poulos PW.Examination of growth plate defects in the distal radial physis of 13 foals three to 70 days of age revealed lesions in the lateral and medial aspects of the distal radial physis; the lateral defects were more numerous and obvious. Lesions consisted of widening of the zone of hypertrophying cells of the metaphyseal growth plate (retained cartilage), retained cartilage with discontinuity of cartilage and primary spongiosa, and microfracture of the primary spongiosa. In some foals, the cartilage retention was thought to be due to primary spongiosa microfracture, although fracture subsequent to c...
Archer RM, Lindsay WA, Duncan ID.This study was designed to define a simple, unequivocal test for the evaluation of laryngeal function and the diagnosis of idiopathic laryngeal hemiplegia (ILH). ILH is a disorder that results from left recurrent laryngeal neuropathy and in which there is no movement of the left arytenoid cartilage and vocal fold. Laryngeal function was evaluated in seven horses using four techniques designed to stimulate laryngeal movements:-nasal occlusion, exercise, swallowing and administration of a respiratory stimulant. In addition, the effects of sedation and twitching on the endoscopic examination were...
Rapp HJ, Weiss R, Bockisch FJ, Becker M, Stechele M.Using the direct sedimentation method, the air pollution with fungal spores was measured in indoor riding arenas and compared to horse stables, outside riding arenas and covered sport courts. Depending on the location of indoor arenas and stables, the presence of "dust-nests", the number of horses ridden, and the moisture of the tread layer, an air pollution was measured which was equivalent to that in stables except at times of feeding and straw-giving. Outside and in sport arenas a low air pollution was found. Recommendations are given, regarding optimum air hygiene especially for horses wit...
Wijnberg ID, Back W, van der Kolk JH.This paper describes a case of unilateral stringhalt present for 18 months in the right hind limb of a 4-year-old Warmblood gelding. The only abnormalities detected by electromyography (EMG) were a prolonged insertion activity, fibrillation potentials, and positive waves at rest and enhanced EMG activity in the right lateral digital extensor muscle on muscle contraction. This was interpreted as denervation and hyperirritability of this muscle. Both similarities and differences with Australian stringhalt could be found. As described for horses suffering from Australian stringhalt, phenytoin sod...
Arndt S, Kilcoyne I, Vaughan B, Dechant JE.To identify etiology, clinical findings, diagnostic results, treatment, and short- and long-term survival and to report factors associated with nonsurvival and survival in horses with peritonitis. Methods: Retrospective study. Methods: Horses (n = 72). Methods: Medical records at William R. Pritchard Veterinary Medical Teaching Hospital from 2007-2017 were reviewed for horses diagnosed with peritonitis. The essential inclusion criterion was a peritoneal nucleated cell count of ≥25 000 cells/μL. Gastrointestinal rupture and cases in which peritonitis occurred after abdominal surgery or cas...
Kirschvink N, Art T, Lekeux P, Roberts C, Gustin P.8-Epi-PGF2alpha, a prostaglandin-like compound generated by oxidative stress, has been shown to be an in vitro bronchoconstrictor in airways from healthy laboratory animals and healthy humans, but it has never been studied in diseased airways. Here, the bronchoconstrictive capacity of 8-epi-PGF2alpha on isolated bronchial rings (BR) of healthy and heaves-affected horses was evaluated by comparing the maximal effect and the potency of 8-epi-PGF2alpha to those of (1) acetylcholine (ACh), (2) its stereoisomer PGF2alpha and (3) its synthetic receptor agonist, U46619. Furthermore, the potential cap...
Weston MC, Collins ME, Cunningham FM.Inappropriately activated eosinophils can contribute to disease pathogenesis and intracellular signalling pathways that regulate functional responses may represent a therapeutic target. Little is known about intracellular signalling in equine eosinophils and this study examined the role of phospholipase C (PLC) and a range of protein kinases on responses to histamine and CCL11. Histamine (10(-4) M) or CCL11 (5.6 x 10(-9) M)-induced actin polymerization, migration and superoxide production by eosinophils from healthy horses were compared in the presence and absence of selective kinase inhibitor...
Stecco R, Paccamonti D, Gutjahr S, Pinto CR, Eilts B.Oxytocin is released in response to teasing during both estrus and diestrus in mares, and at least during estrus, teasing results in an increase in electromyographic activity in the uterus. Exogenous oxytocin causes an increase in intrauterine pressure and prior studies have shown that this response is correlated to the day of the estrous cycle. To determine if teasing causes an increase in intrauterine pressure and if this response varies by day of the cycle, intrauterine pressure was measured while mares were teased with a stallion 2 days before ovulation, on the day ovulation was detected a...
Pellegrini MG, Corda EM, Manca L, Olianas A, Sanna MT, Fais A, Masala B.A study was made of the Hb phenotype of the Sardinian dwarfhorse (Equus caballus jara), one of the last surviving wild horse species in Europe. Hb haplotypes and their frequencies were found to be similar to those described in the Arabian horse (BI = 0.551, BII = 0.389, A = 0.036, V = 0.015), which suggests possible introduction onto the island from North Africa. The oxygen binding properties of the whole hemolysates and of the four different horse Hbs, separated by ion-exchange chromatography, were considered with regard to the effect of chloride, 2,3-bisphosphoglycerate and lactate. Results ...
Pratt SM, Stacy BA, Whitcomb MB, Vidal JD, De Cock HE, Wilson WD.A 13-year-old Morgan gelding was evaluated because of a mass in the caudal region of the abdomen. The horse had been presumed to be a gelding, but necropsy findings revealed a retained testis in the right retroperitoneal space. Histologically, the retained testis contained neoplastic cells; metastases were identified in the liver, spleen, lungs, and sublumbar lymph nodes. Immunohistochemical examination of the testis and metastatic tissues confirmed the diagnosis of malignant Sertoli cell tumor. Testicular neoplasms are infrequently reported in stallions. Seminomas are most commonly reported, ...
Trotter GW.Although many wounds in horses heal successfully by second-intention healing or delayed closure, some wounds can be sutured primarily, with reasonably high expectations of first-intention healing. To expect to achieve these results, one needs to have a rational treatment plan. Such a plan should be based on a working knowledge of the biology of tissue repair and tissue infection. Treatment decisions should be based more on results of experimental and clinical trials rather than on testimonials of other practitioners.
Oikawa M, Ohishi H, Katayama Y, Kushiro A, Yoshikawa H, Yoshikawa T.A mass developed in the mandibular gingiva of a thoroughbred racehorse. When the horse could no longer eat unassisted, it was killed and immediately autopsied. Macroscopically, the mandible exhibited extensive osteolysis, with only a small amount of bone remaining around the tooth roots. The cut surface of the mass around the mandible consisted of neoplastic medullary tissue, in which osteogenesis was observed. The medullary tissue was composed of pleomorphic medium-sized to large cells, interlaced by collagen bundles. These cells had large, pale, round or ovoid, sometimes cleaved nuclei, with...