"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.
Science (New York, N.Y.)September 14, 1984
Volume 225, Issue 4667 1172-1174 doi: 10.1126/science.6089344
Lagerweij E, Nelis PC, Wiegant VM, van Ree JM.The twitch procedure in horses attenuates the increase in the heart rate evoked by pain-inducing stimuli and the reaction of the animals to such stimuli. Endorphin systems are probably involved in the effectiveness of the twitch, since its action is blocked by naloxone and its application increases plasma concentrations of immunoreactive beta-endorphin. The mode of action of the twitch cannot be explained by the generally accepted theory of divertive pain and may resemble that of classical acupuncture.
Chang HC, Takashima I, Arikawa J, Hashimoto N.A biotin-labeled antigen (BLA) was adapted to a sandwich enzyme-linked immunosorbent assay (S-ELISA) for detection of Japanese encephalitis (JE) antibody in a variety of animal sera. JE antigen was fixed on the wells of a microplate and became bound to the specific antibody which could react with a peroxidase-labeled avidin conjugate and azino-di-(3-ethylbenzthiazolin sulfonic acid) (ABTS) as a substrate. The BLA-S-ELISA could simultaneously detect JE antibody in all hemagglutination inhibition (HI) positive sera from man, swine, monkey, horse, cattle, rabbit, rat, mouse and pigeon by using th...
Ludwig KG, Craig TM, Bowen JM.Six mares were treated on the day of parturition with an intramuscular injection of 0.2 mg kg-1 ivermectin and placed in a pasture free of equine parasites as soon as possible after foaling. The mares and their foals were compared with a similar group of untreated mares and foals on an adjoining pasture. The experimental data was derived from mare and foal fecal egg counts, foal necropsies and pasture larval counts. Ivermectin administered to mares on the day of parturition, when combined with movement to parasite-free pastures, significantly lowered the cyathostome (small strongyle) egg produ...
Trim CM.Complications following the use of the cuffless large animal endotracheal tube during general anesthesia in 2 horses are reported. One horse developed laryngeal edema during recovery. The edema was treated successfully with dexamethasone, but severe laryngeal trauma was confirmed 24 hours later at necropsy. The second horse had a swollen tongue and had difficulty eating for 3 days after anesthesia. The condition resolved without treatment. this report is a reminder of the potential damage which can occur from endotracheal intubation.
Didkowski S, Kaminski M, Kerjan P, Tomaszewska-Guszkiewicz K, Zurkowski M.By the method of precipitation with Rivanol (2-ethoxy-6,9-diaminoacridine lactate) and ammonium sulphate followed by chromatography on DEAE cellulose three genetic variants of transferrin were purified from equine serum: D, M and R. Their molecular mass determined in this study was 80 000, and it was identical for all three variants, which differed slightly in their amino acid composition. The protein level was determined in the serum of 535 two-year-old thoroughbred English horses by the method of rocket immunoelectrophoresis using antibodies obtained against three transferrins. The individua...
Bertone AL, Aanes WA.Three cases of unilateral congenital phalangeal hypoplasia are described in 2 horses and 1 mule. Radiographic lesions include severe hypoplasia of the 3rd phalanx, and associated hypoplasia of the 2nd phalanx in 2 cases, and hypoplasia or aplasia of the navicular bone in 2 cases. All animals could ambulate but were lame. Two cases had palpable laxity at the level of the coronary band. Documented etiology was not determined for the dysgenesis, but possibilities include inherited transmission or an environmental teratogen.
Douglas-Hamilton DH, Osol R, Osol G, Driscoll D, Noble H.A field trial of artificial insemination in horses with transproted, chilled semen was conducted using a specially designed container which permitted a controlled, slow initial rate of cooling (-0.3 degrees C/min) and maintenance of a final temperature of 4 degrees -6 degrees C for more than 36 hrs. Forty-six mares in 23 states were inseminated with semen from three German Warmblood stallions standing at stud in Hamilton, Massachusetts. A third-cycle conception rate of 91% was obtained.
The Journal of hereditySeptember 1, 1984
Volume 75, Issue 5 413-414 doi: 10.1093/oxfordjournals.jhered.a109968
Sponenberg DP, Harper HT, Harper AL.A bay roan Brabant Belgian stallion (ERn/ ern) was bred to eight chestnut American Belgian mares (ern/ ern), producing 57 foals. Thirty foals were bay roan, 25 were chestnut, one was bay, and one was chestnut roan. The recombination rate was 0.035 +/- 0.024, indicating fairly close linkage between the roan (Rn) and extension (E) loci.
Pan LG, Forster HV, Bisgard GE, Dorsey SM, Busch MA.We assessed cardiovascular variables and blood O2 contents in order to characterize O2 transport in ponies during treadmill exercise. In normal ponies at 1.8, 3, and 6 mph, respectively, cardiac output (Qc) increased from 12 l/min at rest to maximum levels of 19.7, 28.7, and 39.9 l/min between 30 and 60 s. Qc then decreased to steady-state levels of 18.2, 24.6, and 32.7 l/min by 4 min. Heart rate (HR) showed a similar biphasic response in the 1st min of exercise. Systolic and diastolic arterial blood pressure (BP) decreased at the onset of exercise by 20-25 Torr (P less than 0.05) and then inc...
Vyslouzil L, Seidl K, Svarcová J, Landsmannová V.A case history of mass foal disease which affected ten of the total stock of 50 foals and killed eight is described. The disease was characterized by respiratory disorders and extensive pneumonias with abscess formation, metastatic abscesses in mesenterial lymph nodes and in other organs. As a result of the examination of two dead foals and three nasal smears from diseased animals, gram-positive bacteria were isolated from the lungs, pulmonary and abdominal abscesses and the nasal smears of the affected foals; with their cultivation, morphological and biochemical characteristics these bacteria...
Soma LR, Korber K, Anderson T, Hopkins J.The effects of furosemide (0.55 mg/kg IV) on the plasma and urinary fentanyl (PFE UFE) concentrations were studied during steady-state conditions. The PFE during the steady-state period was 0.31 +/- 0.027 ng/ml, with no significant changes occurring, even though the rate of excretion of fentanyl (EX) increased during the 1st hour from 112.0 +/- 21.6 to 534.5 +/- 82.9 ng/minute. The EX returned to control levels within 3 hours, as did the UFE. The injection of furosemide increased glomerular filtration rate from 1.97 +/- 0.21 to 3.81 +/- 0.75 ml/kg/min. The fractional reabsorption decreased fro...
Musselman EE, LoGuidice RJ.A necropsy diagnosis of hypoplastic left ventricular syndrome was made in a day-old foal. The cardiac abnormalities included mitral and aortic valve atresia, patent ductus arteriosus, and a secundum atrial septal defect. The left ventricle was hypoplastic and nonfunctional. The brief survival of the foal was a consequence of left-to-right shunting through the atrial septal defect and right-to-left shunting through the patent ductus. The information is presented to demonstrate the existence of the syndrome as a congenital defect in the horse and to clarify the necropsy findings for the practiti...
Townsend HG, Leach DH.The anatomical features of 21 equine thoracolumbar spines, obtained from horses with clinically normal backs, were examined and the results compared with recent data on the mobility of the joint complexes of the horse's spine. The thoracolumbar spine can be divided into four regions based upon the morphology of the joint complexes: the first thoracic intervertebral joint (T1-2), the cranial and mid thoracic region (T2-T16), the caudal thoracic and lumbar region (T16-L6) and the lumbosacral joint. The mobility of the intervertebral joints in each of these regions can be related to their morphol...
Vandeplassche M, Simoens P, Bouters R, De Vos N, Verschooten F.In 214 cases of severe dystocia in mares, of which 141 (66 per cent) were Draught horses, deviation of the head and neck, with or without torticollis, malformed head and limbs were found to be the cause of dystocia. No evidence of a genetic lethal factor was found and torticollis was often combined with scoliosis of the head and, frequently, with malformation of one or more limbs. This is considered evidence of a common aetiology and pathogenesis of the syndrome of malformation. The malformations were found to be associated with an increased incidence of caudal and, particularly, transverse pr...
Held JP, Blackford JT.Three cases of vaginal perforation after coitus are discussed. The most consistent clinical sign is a small amount of blood escaping from the vulvar lips immediately after breeding. Secondary infection and posttraumatic swelling may cause abdominal pain due to rectal impaction. Treatment with high levels of an appropriate antibiotic is important to reduce the risk of a severe infectious peritonitis. The use of artificial insemination or a breeding roll to prevent full intromission is recommended.
McCoy DJ, Shires PK, Beadle R.Atlantoaxial subluxation secondary to odontoid fracture in a 30-day-old foal was corrected by alignment of the atlantoaxial joint and stabilization with 2 ventrally placed dynamic compression plates. At 90 days after surgery, healing of the fracture, with adequate alignment of the atlantoaxial joint, was confirmed radiographically. The foal was only slightly tetraparetic at that time. At 1 year after surgery, the gait was normal. It was concluded that the technique has advantages over the use of Steinmann's pins or external coaptation for stabilization. The ventral approach allows decompressio...
Powers JD, Powers TE, Varma KJ, Gabel AA, Spurlock SL.Quantification of the clinical manifestations of a disease has been a serious problem particularly as related to clinical trials or drug efficacy studies. Historically, this quantification has been limited to categorizing each patient into one of three or four groups, e.g. worse, no improvement, improved. This problem becomes serious when an investigation utilizes an experimentally induced animal disease model. A health index, which quantifies the clinical state of horses which have an experimentally induced beta-hemolytic streptococcal infection, is described. Aspects of experimental design a...
Goetz TE, Coffman JR.Ulcerative colitis, protein losing enteropathy and intestinal histoplasmosis-salmonellosis were diagnosed in a six-year-old Quarterhorse stallion. For six months before examination, the horse experienced a slow continual loss of weight. During the 17 day period of hospitalisation the horse developed progressive generalised oedema. On the 12th day of hospitalisation a severe profuse watery diarrhoea began; the horse was killed five days later.
Thurman JD, Johnson BJ, Lichtenfels JR.Arteriosclerosis caused by Dirofilaria immitis adult parasites was diagnosed in a 20-month-old Quarter horse stallion that died from cantharidin toxicosis. Microscopically, the pulmonary vascular changes were typical of those described as "proliferative endarteritis" in D immitis-infected dogs.
Corda M, Pellegrini M, Rinaldi A.Diamine oxidase was prepared from horse kidney by a procedure involving heat denaturation at 50 degrees C, ammonium sulfate fractionation, chromatography on hydroxyapatite and on G-200 Sephadex columns. This procedure gave about 1000 fold purification over the crude kidney cortex homogenate. The enzyme preparations thus obtained are stable only at high ionic strength. The effect on enzyme activity of salt concentration and various stabilizing agents have been investigated. The horse kidney diamine oxidase is irreversibly inhibited by carbonyl reagents and shows substrate specificity quite simi...
Ramey DW, Reinertson EL.A diagnosis of sand enteropathy was made in a 3 1/2-month-old Quarter Horse filly. Clinical signs included diarrhea and weight loss of 2 1/2 months' duration. Abdominal radiographs were useful in diagnosis of the condition and in evaluating response to therapy. The filly responded to treatment with psyllium hydrophilic mucilloid although full recovery took 2 months. Diagnosis and treatment of sand enteropathy is discussed.
van Amstel SR, Reyers F, Colly PA.Variable results were obtained when the starch digestion test was carried out on a suspected case of malassimilation in a horse. In order to re-evaluate this test, 15 starch digestion tests were carried out using 4 horses. Results showed a marked variation in the increase in plasma glucose levels between individual horses and especially between poor and good condition horses when the dose of starch was based on body mass. Results also suggest that a fixed dose of starch may give more consistent results.
Miller PJ, Holmes JR.The anatomy of the equine mitral valve and certain variations observed in 60 adult horses are described. The functional role of this valve, sited between the left atrium and the high pressure-generating left ventricle, is discussed in relation to its anatomical structure. A method of examining the left side of the heart post mortem is described.
Colbern GT, Moore JN.A patellar fracture was identified radiographically in the right stifle of a mature Tennessee Walking Horse stallion. The horse was markedly lame (grade IV/V) on the right hindlimb. Due to the articular nature and small size of the fragment, surgical removal via arthrotomy was selected. A dorsomedial approach to the femoropatellar joint was used. The horse recovered well and has returned to training as a show horse by 8 months following surgery.
Douglas RH, Ginther OJ.Nine groups of pony mares (3/group) were used in a 3 times 3 factorial experiment. The factors were dose of PGF-2 alpha (0, 0.25 of 1.25 mg and route of administration (im, iu or il). Mares were laparotomized and treated on day 7 postovulation. Jugular blood was collected for progesterone RIA at 0 (pretreatment) and 1,6,12,24,48, and 72 hr posttreatment. In mares given either 0.25 mg or 1.25 mg PGF-2alpha, progesterone concentrations were not significantly different among the three routes at any of the posttreatment times studied except at 6 hr posttreatment. In mares given 0.25 mg, progestero...
Odenkirchen S, Huskamp B.Casuistics of 200 patients with acute diarrhea (72 horses with salmonellosis, 55 horses with typhlocolitis, 73 horses with unspecific diarrhea) have been analyzed. It was shown, that horses with salmonellosis have been fallen ill with a primary disease for a longer period of time before the beginning of diarrhea than those with typhlocolitis and that in cases of salmonellosis antibiotics very often were used during the preliminary treatment. Frequently a primary illness of the colon was seen with typhlocolitis. Besides the frequent use of butylscopolamin during the pretreatment was noticed. Th...
Kofler J, Kübber-Heiss A, Schilcher F.Clinical, ultrasonographic and pathological findings of a cutaneous, multilocular T-cell lymphosarcoma (malignant lymphoma) in a 13-year-old, brown Austrian warmblood mare are reported. The horse was under clinical observation, and the tumours were sonographically monitored over an 8 month period, revealing worsening of body condition, weight loss, lameness of the left hindlimb and a slight increase in the tumours size. Most of the tumours were covered by normal skin, one showed ulceration. Ultrasonography of the tumours allowed accurate anatomical localization in relation to the adjoining tis...
May-Davis S, Vermeulen Z, Hunter R, Brown W.For over 200 years, equine anatomic literature has chiefly portrayed the attachment points of the nuchal ligament lamellae (NLL) from the second to the seventh cervical vertebrae (C2-C7). However, recent studies have shown that the modern domestic horse, Equus caballus, primarily exhibits the attachments points from C2-C5. Here we present the rare finding of a complete NLL attached from C2-C7 in one Australian Stock Horse (ASH) and discuss the potential implications of these findings. Previously, this trait has only been confirmed among close descendants of Equus ferus ferus; namely the primi...
Gehlen H, Bubeck K, Rohn K, Stadler P.The aim of this study was to investigate the potential haemodynamic effects of valvular insufficiency and recurrent airway obstruction (RAO) in horses with atrial fibrillation (AF). Therefore in ten healthy horses (group 1) and 40 horses with AF a clinical examination, a lung examination, echocardiography and right heart catheterization for measurement of intracardic and pulmonary pressures were performed. According to the clinical findings the horses with AF were subdivided into 4 groups (group 2: AF; group 3: AF/valvular insufficiency; group 4: AF/RAO; group 5: AF/valvular insufficiency/RAO)...
Rinnovati R, Xenos S, Beltrame A, Marigo A, Forni G, Morini M.A neurofibroma was excised from the subcutis on the medial side of the left thigh of a 15-year-old Warmblood gelding, which had shown lameness of the left hind limb. No other source of lameness was found. Two weeks after surgery, the horse was sound at a lameness examination.
Lloyd KC, Wheat JD, Ryan AM, Matthews M.Sudden onset of hematuria was associated with mucosal ulceration of the proximal portion of the urethra in 1 stallion and 3 geldings. Hematuria was observed characteristically and consistently at the end of urination. Mucosal ulceration was identified endoscopically in the proximal portion of the urethra at the level of the ischial arch. Biopsy of an ulcerated area of the proximal urethra in one gelding revealed transitional cell carcinoma. Treatment regimens varied from systemic antimicrobial and/or vasoactive therapy to diversion of urinary flow via a temporary perineal urethrostomy. Hematur...
López ML, Fuentes P, Retamal C, De Souza W.The occurrence, localization and ultrastructural characteristics of a blood-tissue barrier throughout the stallion proximal seminal excurrent duct system were studied by the exclusion of electron-dense tracers and freeze-fracture techniques. Striking differences were observed in the distribution of lanthanum tracer and in the geometrical organization of the zonulae occludentes along the ductus efferentes, epididymides and vas deferens. The zonulae occludentes domain, the principal structural component of the blood-epididymis barrier, differed in permeability, width and strand numbers along the...
Spier SJ, Meagher DM.Rational perioperative management improves the success rate of abdominal surgery. Important aspects of management are discussed, including principles of fluid therapy, nutrition, intravenous catheterization, antimicrobial prophylaxis, and the use of nonsteroidal anti-inflammatory medication. Current advances in the area of immunotherapy are mentioned.
Wintzer HJ.A long-term treatment with biotin (vitamin H) in 5 warm-blooded horses and 10 trotter horses is reported. The dose of 0.031-0.037 mg/kg body weight was well tolerated, and with a therapy period up to 10 months an improvement of the horn quality of the growing hoof could be attained as it had not been possible before with other measures. Biotin (Gabiotan) is recommendable as a therapeutic in all cases of hoof problems which are based on disturbed horn elasticity.
Vallance SA, Lumsden JM, Begg AP, O'Sullivan CB.To review eight horses diagnosed with idiopathic haemarthrosis and to describe the intra-articular use of yttrium-90 ((90) Y) and methylprednisolone acetate (MPA) in recurrent haemarthrosis cases. Methods: Retrospective case series. Methods: The medical records, diagnostic images, histopathology and outcome of all horses diagnosed with idiopathic haemarthrosis between 1998 and 2010 were reviewed. Results: Four Thoroughbred racehorses with haemarthrosis of the antebrachiocarpal joint had severe acute lameness (median, grade 4) and marked joint effusion after high-speed exercise. Another four ho...
Acutt EV, Zhou T, Mama K, Nelson BB, Selberg KT, Barrett MF.Delivery of mesenchymal stem cells (MSC) via intravascular techniques to treat diffuse and/or inaccessible soft tissue injuries has grown in popularity. The purpose of the current prospective, analytical pilot study was to utilize CT to validate this novel technique and provide additional evidence to support its use for injectate delivery to specific soft tissue structures. Of particular interest was the proximal suspensory ligament, which presents a challenging injection target. Six adult horses without lameness underwent CT of the distal hindlimbs. Scans were obtained prior to ultrasound-gui...
Schumacher J, Cole RC, DeGraves FJ, Cofield LG.To compare the speed of onset and analgesic effect of mepivacaine deposited within or immediately outside the neurovascular bundle at the base of the proximal sesamoid bones in horses. Methods: 6 horses with naturally occurring forefoot-related lameness. Methods: In a crossover study design, horses were randomly assigned to receive 1 of 2 treatments first, with the second treatment administered 3 to 7 days later. Trotting gait was analyzed with an inertial sensor-based motion analysis system immediately before treatment to determine degree of lameness. Afterward, ultrasound guidance was used t...
Grauerholz H, Jaeschke G.After the onset of training ("breaking") in young standardbred horses within continuing investigations changes of vectors in the QRS-complex were considered. These changes accomplished in two stages. Mainly within the first three months of training the vector R (VR) in limb leads changed to the left and to caudal and dorsal. In a second interval between five and seven months after breaking the vector S (VS) changed to cranial. As main cause the different character of training in both phases is discussed. Additional indicators of age- or development-related causes were not found.
Liu IK.Uterine defense against infection in the mare has been actively investigated over the past decade. Mechanisms of defense, including the role of immunoglobulins, polymorphonuclear neutrophils, and the physical ability of mares to eliminate bacteria from the uterus, are discussed.