"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.
Mansmann RA.Little has been written about the use of antibiotics in the horse. This article is based on personal experiences related to equine clinical medicine and literature review and certainly does not represent all the possible therapeutic regimens that can he employed in the horse. There are two concepts that this article will emphasize. First and most importantly, when an infective process is suspected in a patient, cul-tures and sensitivities are the most important determinations to be made prior to antibiotic therapy. Whether in the treatment of a single case or in the treatment of a herd problem...
Muir WW, Moore CA, Hamlin RL.The influence of various concentrations of CO2 and O2 in the inspired gases on minute volume (V), tidal volume (VT), and respiratory rate (breaths per min; BPM) was examined in nonanesthetized, nonsedated normal horses. The VT and BPM increased linearly in response to increases in inspired CO2 concentration and curvilinearly in response to decreases in inspired Os concentration. The V increased curvilinearly in response to both increases in inspired CO2 concentration and decreases in inspired O2 concentration.
Engle CC, Foley CW.Uterine tubal fluids were collected twice a day from mares for 5 consecutive estrous cycles between March 15 and September 1. Follicular fluids were aspirated from the follicles of exteriorized ovaries of 3 mares between days 2 and 5 of estrus. Uterine tubal fluid and follicular fluid were analyzed for osmolarity, dry matter, total lipids, total free fatty acids, glucose, fructose, and lactic acid. Blood samples were collected (jugular venipuncture) throughout the estrous cycle, and the same physical and biochemical analyses were made on blood plasma. A difference (P less than 0.01) was found ...
Targowski SP.Treatment of ponies with a single dose of prednisolone markedly reduced the number of blood lymphocytes. A decrease of the number of eosinophils was also observed. In contrast, the number of neutrophils significantly increased. These profound changes were temporary and returned to the pretreatment level within 48 h. The number of monocytes did not show any of the significant changes post-prednisolone treatment. The reactivity of the blood lymphocytes of these ponies, in vitro, to stimulation with phytohemagglutinin (PHA) or streptokinase-strepto-dornase (SK-SD) was measured by incorporation of...
Dworschack R, Tarr G, Plapp BV.A single amino group in horse liver alcohol dehydrogenase was modified with methyl(14C)acetimidate by a differential labeling procedure. Lysine residues outside the active site were modified with ethyl acetimidate while a lysine residue in the active site was protected by the formation of an enzyme-NAD+-pyrazole complex. After the protecting reagents were removed, the enzyme was treated with methyl(14C)acetimidate. Enzyme activity was enhanced 13-fold as 1.1 (14C)acetimidyl group was incorporated per active site. A labeled peptide was isolated from a tryptic-chymotryptic digest of the modified...
Allen WE.Ten pregnant Welsh pony mares were each treated with a series of three intravenous injections of 2000 iu human chorionic gonadotrophin (HCG) on alternate days. In four mares the first dose was given before the 39th day of gestation and conceptual loss followed treatments in all mares. The other six mares were first treated between the 40th and 97th days. No conceptual loss occurred despite five of the mares being given a fourth dose of HCG. Two mares first treated on days 36 and 38 of pregnancy subsequently produced PMSG although foetal death had occurred.
Bull TE, Lindman B, Einarsson R, Zeppezauer M.The binding of Au(CN)2- and Pt(CN)4-2- ions to the coenzyme binding site of horse liver alcohol dehydrogenase (alcohol : NAD+ oxidoreductase EC 1.1.1.1) has been studied by 35C1 nuclear magnetic relaxation. Longitudinal relaxation rates were analyzed in terms of a simple model and binding constants for Au(CN)2-, Pt(CN)4-2- and C1- were estimated. From a comparison between transverse and longitudinal relaxation rates the correlation time and the quadrupole coupling constant of bound chloride ion were obtained. The quadrupole coupling constant estimated from a simple electrostatic model for chlo...
Harrington DD.Spontaneous Tyzzer's disease is described in quarter horse foals which died suddenly with no clinical history of apparent illness. Significant gross findings included icterus, focal paletan areas in the liver and catarrhal entercolitis. Focal dark red lesions were present in the small intestine of one foal, and the mesenteric lymph nodes of another were enlarged and hyperemic. Histopathologically, the liver showed multiple discrete and confluent foci of necrosis, fatty change, sinusoid congestion and haemorrhage. Bundles of intracytoplasmic bacilli were demonstrated in hepatocytes at the margi...
Hayes HM, Priester WA, Pendergrass TW.From 11 North American veterinary university hospitals and clinics, 248 animals were a confirmed diagnosis of nervous-tissue tumor were identified; 7 tumors were found in cattle, 28 in horses, 14 in cats, 199 in dogs, and none in other species. Tumors were divided for analysis into three categories-glial, meningeal, and peripheral nerve. In cattle and horses, all tumors involved peripheral nerves, the risk of which, in horses, reached a plateau at 4-6 years of age and remained constant thereafter. In cats, the tumors were equally distributed among the three tumor categories whereas, in dogs, t...
Powell DG.During the past 20 years the equine population of Great Britain and Ireland has increased with the result that the practising veterinary surgeon is more frequently called upon to advise on equine problems. A significant portion of this advice is concerned with the examination of horses showing signs of this advice is concerned with the examination of horses showing signs of respiratory disease. Numerous pathogens, which include viruses, bacteria, parasites and moulds invade the respiratory tract causing similar signs of illness. It is therefore difficult to provide an aetiological diagnosis ba...
Ford GH, Empson RN, Plopper CG, Brown PH.Masses removed from the superficial fascia of the jugular groove of a 12-year-old Arabian mare and from the femoral canal of a 7 1/2-year-old female cat appeared to be counterparts of the human malignant giant cell tumor of soft parts, even recapitulating the clinical behavior of the respective subgroups. Histologically, both neoplasms contained the characteristic features of the malignant giant cell tumor of soft parts: large multinucleate giant cells, pleomorphic mononuclear giant cells, histiocytes, fibroblasts and fibrocytes that were sometimes sarcomatous, and foci of hemorrhage and necro...
Krook L, Wasserman RH, Shively JN, Tashjian AH, Brokken TD, Morton JF.A chronic debilitating disease is described in Florida horses. There is progress weight loss and lameness of increasing severity. Plasma calcium is elevated to moderate or severe degree. Anatomical changes include dystrophic calcinosis of elastic tissues, viz. major arteries, tendons and ligaments. A generalized osteopetrosis is present and may be related to hypoparathyroidsim and hypercalcitoninism. The presence of Cestrum diurnum (day-blooming jessamine, day cestrum, wild jasmin) in areas accessible to affected animals, the observation that leaves of the plant were stripped in these areas, a...
Lewis GE, Huxsoll DL, Ristic M, Johnson AJ.Dogs (German Shepherd Dogs and Beagles), cates, rhesus macaques (Macaca mulatta), and baboons (Papio anubis) were inoculated with Whrlichia equi, the etiologic agent of equine ehrlichiosis. Within 3 to 7 days after inoculation, morulae were observed in the eosinophils of cats, neurtrophils of macaques and baboons, and in both neutrophils and eosinophils of dogs. The severe disease produced in horses by this agent was not a feature of E equi infection in dogs, cats, macaques, and baboons. However, a susceptible horse, inoculated with the pooled blood of 2 infected macaques, developed severe cli...
Wensing T, van Gent DM, Schotman AJ, Kroneman J.(I) The lipid and lipoprotein concentrations in sera of 4 healthy and 9 hyperlipaemic patients were determined. From the results of the analyses, it is suggested that three types of hyperlipoproteinaemia can be distinguished in ponies: (a) Type 1, characterised by a very pronounced increase in only the very low density lipoproteins (VLDL); (b) Type 2, in which there is a pronounced increase in the chylomicrons (Chylo) and the very low density lipoproteins (VLDL); (c) Type 3, which can be the result of fasting and is characterised by a moderate increase in the concentration of chylomicrons and ...
Toniolo C, Fontana A, Scoffone E.Ultraviolet absorption and circular dichroism studies have been carried out on horse heart apo-cytochrome c and heme-free peptide fragments obtained by cyanogen bromide cleavage of the native protein. It was noted that the various peptides assume predominantly an unordered conformation in water solution. Increasing ionic strength and addition of 2-chloroethanol increase the right-handed helical content. Guanidinium hydrochloride favors the coil state. It was also demonstrated that two non-interacting helical regions of different stability are present in the apo-protein in 2-chloroethanol.
Rastegaev IuM.10 foals were artificially infected for the first time with eggs of Gastrophilus intestinalis, G. veterinus, G. haemorrhoidalis, G. inermis, G. nigricornis. 63 to 67% of the 1st stage larvae die in the first period of life after emergence from the egg, at the moment of invasion into the skin and at the beginning of the migration. In 40 to 45 years after the infection most larvae (73 to 82%), depending on their specific belonging, were found in the stomach, duodenum and rectum.
Desantis S, Santamaria N, Zizza S, Accogli G, Mastrodonato M, Scillitani G, Mentino D.Urothelium is a multilayer epithelium covering the inner surface of the urinary bladder that acts as a blood-urine barrier and is involved in maintaining the wellbeing of the whole organism. Glycans serve in the maturation and differentiation of cells and thus play a key role in the morphology and function of the multilayered epithelium. The aim of the present study was to examine the glycoprotein pattern of the horse urinary bladder urothelium by lectin histochemistry. Methods: The study involved urinary bladders from four horse stallions. Tissue sections were stained with a panel of eleven l...
Frei S, Fürst AE, Sacks M, Bischofberger AS.Three horses that were presented with supraglenoid tubercle fractures were treated with open reduction and internal fixation using distal femoral locking plates (DFLP). Placing the DFLP caudal to the scapular spine in order to preserve the suprascapular nerve led to a stable fixation, however, it resulted in infraspinatus muscle atrophy and mild scapulohumeral joint instability (case 1). Placing the DFLP cranial to the scapular spine and under the suprascapular nerve resulted in a stable fixation, however, it resulted in severe atrophy of the supraspinatus and infraspinatus muscles and scapulo...
James FM, Smith MRW, Wright IM.Fractures of the proximal phalanx are one of the most common long bone fractures of Thoroughbred racehorses. Although the degree of disruption and damage to the articular surface is generally considered a major prognostic determinant, associated arthroscopic findings have not previously been reported. Objective: To describe the metacarpo/metatarsophalangeal (MCP/MTP) joint lesions associated with parasagittal fractures of the proximal phalanx arthroscopically identified at the time of fracture repair and compare radiographic and arthroscopic appearance of complete fractures. Methods: Retrospec...
Adeyefa CA.Serological evidence of Equine Herpes virus type 1 (EHV-1) activity in Polo horses in Nigeria is reported for the first time. Eighty-two percent of horses tested with known antigen had precipitating antibodies to EHV-1 while 43% of sera tested against antigen prepared from nasal discharges were positive suggesting that the virus was being excreted in the nasal discharges and probably acting as a source of infection for incontact animals as occurs in on-going acute infections. The result of this study indicates a high prevalence of EHV-1 activity among Polo horses in Nigeria and demonstrates th...
Peli A, Roccaro M.Catastrophic injuries in racehorses mostly involve the metacarpal region. Although many studies describe fractures of equine limbs, few examine the relationship between bone morphometrics and musculoskeletal problems in racing horses. And yet, according to the regulation of some Italian traditional races, the shin circumference represents a qualifying prerequisite for horses to be admitted to races. This study aims to evaluate the conformity of the shin circumference measurement in living animals and in post‑mortem examinations, in order to evaluate the forensic reliability of these measurem...
Assis RA, Kuchler IL, Miekeley N, Tozzi MB.Capillary electrophoresis coupled to inductively coupled plasma mass spectrometry was used in a speciation study on disodium monomethylarsonate (DS-MMA(V)) and its metabolites in horses, to which the drug was administered by intramuscular injection on five consecutive days at a single arsenic dosage of 270 mg day(-1). Samples of urine, whole blood, plasma, and mane hair were analyzed before, during, and after drug administration. The data show that blood clearing and urinary excretion of MMA is a fast process following first-order kinetics with biological half-lives of about 38 h and 44 h for ...
Lima AG, Costa LC, Alvarenga MA, Martins CB.The presence of anovulatory haemorrhagic follicles during the oestrous cycle of mares causes financial impacts, slowing conception and increasing the number of services per pregnancy. Non-steroidal anti-inflammatory drugs (NSAIDs) such as meloxicam and phenylbutazone are used in the treatment of several disorders in mares, and these drugs can impair the formation of prostaglandins (PGs) and consequently interfere with reproductive activity. This study aimed to evaluate the effects of treatment with NSAIDs on the development of pre-ovulatory follicles in mares. In total, 11 mares were studied o...
Peck KE, Hines MT, Mealey KL, Mealey RH.To validate use of high-performance liquid chromatography (HPLC) in determining imipramine concentrations in equine serum and to determine pharmacokinetics of imipramine in narcoleptic horses. Methods: 5 horses with adult-onset narcolepsy. Methods: Blood samples were collected before (time 0) and 3, 5, 10, 15, 20, 30, and 45 minutes and 1, 2, 3, 4, 6, 8, 12, and 24 hours after IV administration of imipramine hydrochloride (2 or 4 mg/kg of body weight). Serum was analyzed, using HPLC, to determine imipramine concentration. The serum concentration-versus-time curve for each horse was analyzed se...
Sobiraj A, Bostedt H.This review article deals with a critical comparison between the direct clinical diagnosis for the pregnancy of the mare (rectal and in some cases also vaginal exploration) and indirect methods. Both methods are discussed whether they can be seen as a mutual completion or are suitable for their own. The indirect methods for the pregnancy diagnosis include the hormone-analytic tests as progesterone concentration in serum or milk, the biological and immunological measurements for PMSG in the serum, finally the biological and chemical methods for estrogen contents in the urine of the mare. Furthe...
Blendinger C, Müller G, Bostedt H.The lethal white foal syndrome (congenital intestinal aganglionosis) was diagnosed by history, clinical signs and pathological findings in a female foal, born in March 1992, that was an offspring of two overo-spotted paint horses. The syndrome is a congenital innervation defect of the gastrointestinal tract. A literature review of this condition, relatively unknown in Germany, is given.
Deriusheva SE, Loginova IuA, Chiriaeva OG, Iasinetskaia NI, Efimov AM.Restriction endonuclease in situ digestion of metaphase chromosomes gives an opportunity to reveal strips with different structure within GC-rich pericentric heterochromatin of the domestic horse and the wild Przewalski horse. Blocks of heterochromatin, which are insensitive to HaeIII and brightly stained with chromomycin A3 after restriction enzyme digestion, are localized on the border with euchromatin in the majority of chromosomes of Equus caballus and E. przewalskii. In contrast to chromosome 5 of E. caballus, acrocentric chromosomes of E. prezewalskii which are homologous to this chromos...
Roser JF, Dudan F, Little TV, Livesay-Wilkins P, Hillman RB.Studies were undertaken to investigate the effects of oxytocin induction on prolactin release in term (Group II) and preterm (Group III) mares and to compare these effects to spontaneously foaling mares (Group I). Since physiological concentrations of prolactin in blood have not been measured in the neonatal foal, experiments were designed to monitor prolactin in the cord artery and jugular blood of the foals from all groups of mares. Although prolactin levels varied in term mares (Group I and II) during the last 11 days of pregnancy, an increase was observed between Day -6 and Day 0 (2.7 and ...
Bienert-Zeit A, Müller JM, Feige K.The article provides hands-on advice and scientific background information regarding the management of the equine acute colic patient. It summarizes essential information on the patient's history, clinical examination, and legal aspects. The scope of the history is based on the clinical appearance of the patient. In horses with violent and barely controllable signs of pain, it is limited to colic-associated information such as onset, course and severity of colic signs, and the last time of defecation, as well as prior therapeutic intervention. In these patients, the clinical examination is foc...
Bristol DG.Caudally based axial pattern and random pattern skin flaps, 5 cm x 10 cm, were raised on the abdomens of seven foals. Blood flow was measured 7.5 cm from the flap bases during incremental increases in applied tension. At tensions less than 1400 g, cutaneous blood flow was more than four times higher in axial pattern flaps than in random pattern flaps. Blood flow in axial pattern flaps at tensions up to 1500 g was greater than baseline flow in random pattern flaps. After removal of applied tension, perfusion in axial pattern flaps gradually increased but remained below baseline values. A short ...
