"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.
Rose RJ, Ilkiw JE, Hodgson D.Thirty-one horses competing in a 100 kilometre endurance ride had electrocardiograms recorded before and after the ride from which the heart score of each horse was calculated. Blood was also taken to determine the packed cell volume (PCV) and total plasma protein (TPP) before the ride, after 60 kilometres (mid ride) and at completion of the ride. Statistical analysis of the heart scores showed that a faster group of horses had significantly higher heart scores than either a slower group or those eliminated due to inadequate recovery of heart rate. No horses developed electrocardiogram abnorma...
Slone DE, Bergfeld WA, Walker TL.A filly with ataxia and splinting and crepitation in the neck was found to have atlantoaxial subluxation. Radiographic diagnosis was based on the same criteria as those used in other species, ie, increased distance between the atlas and spine of the axis and increased distance between the dens and floor of the atlas. Extensive hemilaminectomy was performed to decompress the spinal cord. Stabilization was not attempted. Immediate postoperative response was encouraging, but the untimely death of the filly prevented further evaluation of the procedure.
Barnard BJ.The most obvious symptoms of rabies in farm animals and pets in South Africa and South-West Africa are discussed in the light of information obtained during routine examination of specimens for the 10-year-period 1967--1976. More than 55% of the cases encountered were cattle in which the most obvious symptoms were salivation (92%), bellowing (69%), aggressiveness (47%), paresis or paralysis (30%) and straining (12%). Unlike cattle, the most obvious symptom in goats was aggressiveness (83%). Salivation was observed in ony 29% of goats but, like bellowing in cattle, bleating was very obvious in ...
Fujimiya Y, Perryman LE, Crawford TB.Antibody-dependent cellular cytotoxicity and direct cytotoxicity assays were performed with equine infectious anemia virus-infected target cells, equine leukocytes, and equine anti-equine infectious anemia virus antibody to determine whether these mechanisms play a role in controlling viral replication in equine infectious anemia. Direct cytotoxicity was observed by using peripheral blood mononuclear cells from 7 of 10 infected horses. Antibody-dependent cellular cytotoxicity was not observed. The antibody-dependent cellular cytotoxicity reaction in horses was then studied by using sheep eryth...
Drudge JH, Lyons ET, Tolliver SC, Kubis JE.The efficacy of oxibendazole given at dose level of 10 mg/kg of body weight was determined by 10 critical tests in foals and by 2 clinical trials in 20 foals (16 treated, 4 nontreated), with special interest in the drug activity against Parascaris equorum. The drug was uniformly efficacious (100%) against P equorum in the 10 critical-test foals, each having between 22 and 236 ascarids. Posttreatment reductions of ascarid egg counts in fecal samples were also 100% in suckling foals treated with oxibendazole given as a drench. Ascarid eggs did not reappear in fecal samples until the 8th week aft...
Valdez H, Taylor TS, McLaughlin SA, Martin MT.Removal of abdominal testes was accomplished in 32 horses ranging in age from 6 to 72 months. Twenty were unilateral and 12 were bilateral abdominal cryptorchids. An incision was made over the superficial inguinal ring, and the extension of the gubernaculum testis was identified and grasped with forceps. Traction was applied to this structure until the vaginal process was everted beyond the superficial inguinal ring. The vaginal process was incised and the protruding structure, usually the epididymis, was grasped. The testis was drawn out by gentle traction on the epididymis, and castration wa...
van Nie CJ, van der Kamp JS.A case of tricuspid atresia in a premature foal associated with large atrial septal and ventricular septal defects is reported. This anomaly is compared with other cases in horses as reported in the literature. As tricuspid atresia in horses is usually not diagnosed so that relatively few cases have been reported, a classification similar to that of human anomalies is not possible. It is suggested that the present malformation is due to abnormal development of the atrioventricular canal. The factors involved in the pathogenesis of this abnormal development are obscure.
Liberatori J, Morisio Guidetti L, Conti A.By double diffusion in agarose gel, in well defined experimental conditions, cross reactions were observed between porcine beta-lactoglobulins and anti-bovine beta-lactoglobulin antisera. The immunological reactivity between these beta-lactoglobulins from a monogastric and the ruminant anti beta-lactoglobulin antiserum thus implies a certain degree of similarity between the monomeric beta-lactoglobulins examined and the dimeric of the ruminants. With the same antisera it also proved possible to demonstrate the presence of beta-lactoglobulins in the mammary secretions of another monogastric, na...
Houghton E, Dumasia MC.1. After intramuscular administration of [4-14C]testosterone to two cross-bred gelded horses, 45% of the radioactivity was excreted in urine in 96 h. Small amounts of urinary activity could still be detected at 200 h. 2. Neutral metabolites obtained after both enzyme and acid hydrolysis of urine samples have been investigated by g.l.c.-mass spectrometry. 3. 5 alpha-Androstane-3 beta, 17 alpha-diol was found only in the enzyme-hydrolysable extract and testosterone only in the acid-hydrolysable extract. 5 alpha-Androstane-3 beta, 17 beta-diol and 3 beta-hydroxy-5 alpha-androstan-17-one were foun...
Eiler H, Goble D, Oliver J.The plasma concentration of hydrocortisone was determined in mares given either cosyntropin (100 IU, given IV) or corticotropin (200 IU, given IM). Plasma hydrocortisone concentrations of the mares treated with cosyntropin increased by 46%, 57% and 80% at 30, 60, and 120 minutes, respectively, when compared with base-line values; these values returned to base line at 240 minutes. In mares treated with corticotropin, mean plasma hydrocortisone concentrations increased by 42%, 143%, 101% and 155% at 30, 60, 120, and 240 minutes, respectively, when compared with base-line values. Differences in t...
Grenager NS, Durham MG.This report describes the use of ultrasound to diagnose right dorsal displacement of the large colon (RDDLC) in 13 horses prior to surgery. Horses had ultrasonographic examinations performed of the right lateroventral aspect of the abdomen upon admission to the hospital with a 2-5 MHz broadband curvilinear sector scanning transducer after alcohol was used to wet the hair. First, the caecal vessels were identified in the right flank and followed medially and cranially. Next, each intercostal space, from caudal to cranial, was scanned from dorsal to ventral evaluating for abnormally-located mese...
Houle JJ, Hoffmann EM.A passive hemolysis assay system was developed which permitted comparisons of the hemolytic activities of complement (C) from six species. This system employs a single antigen and an antiserum raised in one species. Thus, variations resulting from different target antigens and those inherent in using antibodies (of different affinities and isotypes) raised in a variety of species were minimized. Of the erythrocytes (E) examined, those from horses and guinea pigs were most susceptible to lysis, and either would be suitable, as a tentative choice, for measuring C activity of a previously unstudi...
Fenton JI, Orth MW, Chlebek-Brown KA, Nielsen BD, Corn CD, Waite KS, Caron JP.The effect of longeing and glucosamine supplementation on known biological markers of joint disease was studied in yearling quarter horses. Twenty-one yearling quarter horses were randomly assigned to one of 4 treatments: 1) longeing (longeing 20 min daily) supplement control (LN); 2) longeing/glucosamine (LG); 3) walking (mechanical walker for 120 min daily (WN)); and 4) walking/glucosamine (WG). Oral glucosamine was administered at 5.5 g b.i.d. weeks 1-4, 3.5 g b.i.d. during weeks 5-6, and 2.0 g b.i.d. during weeks 7-8. Serum was obtained weekly for 8 wk and analyzed for keratan sulfate and ...
Geburek F, Deegen E, Hewicker-Trautwein M, Ohnesorge B.Verrucous pastern dermatitis is a chronic hyperplastic dermatopathy of the feet of horses which is characterized by a greasy, odorous coating of the skin and, in advanced stages, by clearly demarcated calluses and wart-like proliferations. The disease occurs almost exclusively in cold-blooded and other heavy horses, with certain breeds affected most frequently. It is considered a distinct disease entity within the framework of pastern dermatitis syndrome. There is no consensus in the literature about relationship of the disease to the sex and age of the horse. Horses with a high cannon circumf...
Moore JN, Garner HE, Shapland JE, Roberts MC.The infusion (IV) of prostacyclin (PGI2) into conscious ponies resulted in systemic arterial hypotension and tachycardia. Mean systemic arterial pressure decreased from 103.3 mm of Hg to 88.5 mm of Hg when 125 ng of PGI2/kg/minute was infused, and heart rate increased from 55.0 to 102.0 beats/minute. When 208 ng of PGI2/kg/minute was infused, mean systemic arterial pressure decreased from 103.3 to 78.0 mm of Hg and heart rate increased from 55.0 to 109.3 beats/minute. There were no significant alterations in pulmonary arterial pressure, lactate, PCV, total WBC count, platelet count, serum lact...
Bugno-Poniewierska M, Dardzińska A, Pawlina K, Słota E.A normal course of meiosis and the associated course of spermatogenesis in males are very significant from the viewpoint of animal breeding, in particular animal reproduction. This takes on special significance when studying late-maturing animals such as horses. The aim of the study was to analyse meiotic cells, with particular consideration of synaptonemal complexes obtained from the testes of young stallions and cryptorchids, based on observations of the X-Y bivalent. The analysis was performed in successive stages of meiotic division using the FISH technique. The greatest diversity and most...
Shams Eldin HE, Kirchhoff H.Tracheal swabs were taken from 25 horses with respiratory diseases and investigated for mycoplasmas using three different media. Mycoplasmas could be isolated from 5 horses. The isolates were characterized by serological and biochemical methods. Four isolates could be identified as Mycoplasma equirhinis. The fifth isolate could not be typed. It did not react with antisera against mycoplasmas found in the respiratory tract of horses and its biochemical characteristics were different from the mycoplasmas described so far. It may represent a new species.
Turk MA, Thomas DE.To study the role of cytochrome P-450-dependent mixed function oxidase reactions in equine 3-methylindole (3MI) toxicosis, ponies were given 20 mg of phenobarbital/kg of body weight at 72, 60, 48, 36, and 24 hours before 100 mg of oral 3MI/kg to induce cytochrome P-450 or no treatment (controls). Maximal 3MI plasma concentration was decreased and clearance was faster in phenobarbital-treated ponies. Plasma 3MI was still detectable 12 and 36 hours after dosing in phenobarbital-treated and control ponies, respectively. Phenobarbital treatment induced a distribution phase with transition from a 1...
Starick E.A reverse transcription-polymerase chain reaction (RT-PCR) assay using four different primer pairs for the detection of equine arteritis virus (EAV) RNA in semen and tissue samples was evaluated. A fragment encoding the leader sequence of the EAV genome was most successfully amplified. The specificity and sensitivity of RT-PCR was assessed by virus isolation in cell culture, restriction analysis, dot blot hybridisation and nested PCR. To this end, 23 semen samples from seropositive stallions and 11 tissue samples from 4 aborted foals were tested. Compared to the virus isolation test in cell cu...
Pintore MD, Cantile C.A full-term male foal born in a farm holidays in Maremma (Tuscany, Italy) was euthanized shortly after birth due to the presence of several malformations. The rostral maxilla and the nasal septum were deviated to the right (wry nose), and a severe cervico-thoracic scoliosis and anus atresia were evident. Necropsy revealed ileum atresia and agenesis of the right kidney. The brain showed an incomplete separation of the hemispheres of the rostral third of the forebrain and the olfactory bulbs and tracts were absent (olfactory aplasia). A diagnosis of semilobar holoprosencephaly (HPE) was achieved...
Robertson SA.Three different anaesthetic techniques were studied in normal, healthy Thoroughbred or Thoroughbred type horses. These were (a) acepromazine, thiopentone and suxamethonium; (b) acepromazine, glyceryl guaiacolate and a 'half-dose' of thiopentone; and (c) xylazine and ketamine. Anaesthesia was maintained with halothane vaporized in oxygen and nitrous oxide. All horses underwent either laryngeal or body surface surgery. Heart rate, packed cell volume, blood glucose and lactate, plasma non-esterified fatty acids, insulin and cortisol were measured before, during and after surgery. The greatest met...
van Leeuwen W, Noden PA, Dieleman SJ.Three experiments were conducted to test the abortifacient effects of PGF2 alpha analogues on mares during midgestation (average gestation length 141.5 days). The progesterone concentration was measured by radioimmunoassay. In experiment 1. five mares received an injection of PGF2 alpha analogue (fluprostenol: 500 micrograms intramuscularly) and a second injection either at 24, 48, of 72 h. Although the progesterone concentration decreased (P less than 0.05) an average of 44 per cent in 24 h, none of the pregnancies were terminated. In experiment 2, beginning at least 10 days after experiment ...
