"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.
Steffey EP, Zinkl J, Howland D.The potential toxicity to horses of 7.33 +/- 0.87 SD minimal alveolar concentration hours of isoflurane anesthesia was evaluated by sequential determination of blood cell counts, electrolyte concentrations, and certain blood chemical values. Minimal or no serious toxicosis was observed for up to 7 days after anesthesia was terminated.
Torbeck RL, Prieur DJ.Cartilaginous defects were created in the radiocarpal joints of 12 horses. Synovial fluid cytologic features, lysozyme activity, and beta-glucuronidase activity were monitored for 16 days. A comparison was made of plasma lysozyme and beta-glucuronidase activity and of synovial fluid lysozyme, beta-glucuronidase, and leukocyte concentrations. Plasma lysozyme was found to be independent of synovial fluid lysozyme activity. Synovial fluid lysozyme was significantly increased (P less than 0.001) in all joints with surgically induced defects (group I) compared with controls (arthrocentesis done; gr...
Flood PF, Jong A, Betteridge KJ.The oviducts of 24 mares were examined to determine the site of retention of unfertilized eggs. The ampullary-isthmic junction regions of 42 of the 48 oviducts were serially sectioned and examined histologically. The remaining parts of the oviducts were flushed and the flushings searched microscopically. Of 45 eggs located, 40 were in the sectioned segments of 24 oviducts and only 5 were in the flushings. All but one of the sectioned segments contained prominent masses of material obstructing the lumen, but these were apparently not the direct cause of egg retention since eggs were found on bo...
Murphy JR, McPherson EA, Lawson GH.80 mg sodium cromoglycate (SCG) was administered by inhalation to two COPD-affected animals known to have respiratory hypersensitivity to Micropolyspora faeni. SCG treatment 20-30 minutes prior to inhalation challenge with M. faeni prevented exacerbation of respiratory disease, usually seen 4-8 hours after challenge. duration of protection against antigen challenge after a single SCG treatment was 4-5 days. The duration of protection was not prolonged by reducing the frequency of antigen challenge. Multiple antigen challenge, using M. faeni and Aspergillus fumigatus, shortened the protective p...
Kelly DF, Pinsent PJ.A 10-month-old thoroughbred colt developed sudden complete blindness; no other neurological abnormality was detected. At necropsy 3.5 months later lesions were confined to both optic pathways in which there was extensive degeneration of axons and myelin and gliosis. The cause of the optic lesion was not determined but the lesion may be a toxic neuropathy.
Snow DH.In the horse the effect of the adrenergenic agonists adrenaline, phenylephrine and salbutamol on haematocrit, plasma free fatty acid, glycerol and lactate levels were investigated. Effects on heart rate, sweating and muscle tremor were also studied. The effects of administration of the adrenoceptor antagonists propranolol, metoprolol, H35/25 and acepromazine on adrenaline-induced changes were examined. The results obtained with these agonists and antagonists suggest that the lipolysis and hyperglycaemia are mediated via beta-adrenoceptors. It appears that both beta1 and beta2 subtypes are invo...
Froscher BG, Nagode LA.Alkaline phosphatase isoenzymes from small intestine, cecum, large colon, small colon, liver, kidney, leukocytes, and serum from ten clinically normal horses were defined by their sensitivities to L-phenylalanine, L-homoarginine, levamisole and heat, and by polyacrylamide gel disc electrophoresis. Readily identifiable isoenzymes occurred in small intestine, granulocytes, kidney, cecum, and large and small colon. By contrast, alkaline phosphatases from liver, lymphocytes, and serum could not be discriminated by this group of tests.
Kovár J, Dürrová E, Skurský L.The interactions of three groups of probes (berberine alkaloids, tricyclic psychopharmaca and acridine derivatives) with isoenzymes of horse liver alcohol dehydrogenase and with rat liver alcohol dehydrogenase have been examined. These compounds inhibit the activity of the EE isoenzyme of horse liver alcohol dehydrogenase but differ in their behaviour towards the steroid-active enzymes (i.e. the ES isoenzyme of horse liver alcohol dehydrognase and alcohol dehydrogenase from rat liver): psychopharmaca inhibit, acridines activate and berberines do not bind. The ligands differ also in their influ...
Brown JE, Corstvet RE, Stratton LG.Two experiments incorporating 13 mares were conducted for the purpose of producing and monitoring intrauterine infection with Klebsiella pneumoniae. In the pilot study, the infection was produced with strains of K pneumoniae type 68 and type 10 isolated from the genital tract of stallions with a history of breeding problems. In the principal study, K pneumoniae type 68 was used to produce the infection. Tampons and guarded culture swabs were used to obtain uterine samples in the pilot study. In comparing the efficacies of isolation of K pneumoniae with the tampons and isolation with standard g...
Hjortkjaer RK, Svendsen CK.Experimental closed loop small intestinal volvulus was studied in the anesthetized horse. Volvulus was simulated by ligation of the mesenterial veins to a segment of small intestine. Physical signs and hemodynamic, hematologic, clinical chemical, bacteriologic and peritoneal fluid values were examined. Compared to conscious horses anesthesia highly delayed and modified the clinical signs of shock (changes in mucosal colour, dehydration, decreased skin temperature, elevated pulse rate, low blood pressures) and of small intestinal volvulus (altered peristalsis, gastric dilation). Plasma glucose ...
Speirs VC, Hilbert BJ, Blood DC.This paper describes the clinical signs and surgical treatment of 2 cases of dorsal displacement of the left ventral and dorsal colon. The condition, in which the colon becomes enclosed in the space bounded by the base of the spleen, the dorsal aspect of the suspensory ligament of the spleen (phrenicosplenic ligament), the left kidney and the adjacent body wall, is characterised by moderate to severe pain, minimal signs of shock, no response to medical therapy and a tendency for a ventral midline abdominal paracentesis to enter the spleen. Both horses recovered after surgical replacement of th...
Clayton HM, Duncan JL, Gilbert GA.Over a period of several years the use of pyrantel embonate in the control of helminth infections on three equine establishments was monitored by the examination of faecal samples collected immediately before each anthelmintic treatment. With a monthly interval between treatments for three years the faecal egg output of the horses remained at a very low level. One one establishment this was maintained when the treatment interval was extended to one-and-a-half months after treating monthly for two years. If a treatment interval of one-and-a-half months was used continuously for a number of year...
Allen WE, Kessy BM, Noakes DE.Two experimental procedures were investigated in order to assess their usefulness in diagnosing occlusion of the equine uterine tube. The starch grain test, which involves the injection of a starch suspension onto the ovary and the subsequent recovery of starch from the cervix, proved to be safe and reliable. Each tube could be investigated separately. It was found that when starch was injected onto the ovulating ovary on the day of ovulation, there was a delay of four to seven days before starch was recovered from the cervix. The phenolsulphonphthalein (PSP) test, which involves the depositio...
van der Linde-Sipman JS, Goedegebuure SA, Kroneman J.In this article a description is given of the clinical and postmortem findings of a persistent right aortic arch in association with a persistent left ductus arteriosus and a ventricular septal defect in a horse.
Prescott JF, Markham RJ, Johnson JA.Transformation of peripheral blood lymphocytes from pony foals vaccinated and subsequently infected with Corynebacterium equi was studied. Three foals were vaccinated on two occasions using a formalinized C. equi vaccine with aluminum hydroxide as an adjuvant. Three nonvaccinated foals served as controls. Foals were challenged intratracheally with 9 x 10(9) C. equi six weeks after the initial vaccination. Foals survived this infection for one to two weeks. Significant lymphocyte transformation in response to C. equi antigens was detected in two vaccinated foals at the third week after initial ...
Colton SW, Downing DT.The relative efficiency of acetate and glucose as substrates for the biosynthesis of lipids in the skin of the rat and horse was examined using in vivo pulse labelling of skin with [1-14C]acetate and [U-14C]glucose by intradermal injections. The resulting radiolabelled lipids were recovered in the rat by punch biopsy as well as by daily, long-term skin surface lipid collections and in the horse by punch biopsy of the injection sites. The lipids were examined by liquid scintillation and by a combination of thin-layer chromatography and autoradiography. In both species the recovery of radiolabel...
O'Brien T, Hunt RJ.In all surgeries with the patient standing under chemical and physical restraint, patient compliance is of the utmost importance. All fractures of the third metacarpal or metatarsal condyles and sagittal fracture of the first phalanx are not amenable to internal fixation with the horse standing, and young unhandled horses may not have a suitable disposition for standing surgical treatment of septic pedal osteitis, or implantation and removal of transphyseal screws. Previous operator experience in performing the procedure or technique under general anesthesia is beneficial. Appreciation of appr...
Kwok KY, Chan GHM, Kwok WH, Wong JKY, Wan TSM.Selective estrogen receptor modulators (SERMs) are chemicals that possess the anti-oestrogenic activities that are banned 'in' and 'out' of competition by the World Anti-Doping Agency (WADA) in human sports, and by the International Federation of Horseracing Authorities (IFHA) in horseracing. SERMs can be used as performance-enhancing drugs to boost the level of androgens or to compensate for the adverse effects as a result of extensive use of androgenic anabolic steroids (AASs). SERMs have indeed been abused in human sports; hence, a similar threat can be envisaged in horseracing. Numerous an...
Hameury L, Delavous P, Leroy C.Hippotherapy uses relationships with horses as a mediation method. The care treatment aims to act on the psychological functioning of children affected by relational disorders, especially in order to help the development of communication and emotions. A partnership has been established between the paedopsychiatric university centre at the CHRU in Tours (37) and a horse-riding centre.
Moore BR, Reed SM, Kowalski JJ, Bertone JJ.A National Show Horse with a mediastinal granuloma was presented with clinical signs which included fever, nasal discharge and cough. The mediastinal mass was identified radiographically and ultrasonographically. A presumptive diagnosis of aspergillosis was made following isolation of Aspergillus spp. from both transtracheal aspirate and bronchoalveolar lavage fluid samples and agar gel immunodiffusion (AGID) identification of serum antibody to Aspergillus spp. The diagnosis was confirmed by histopathologic examination of the mediastinal mass obtained at necropsy examination.
Hadlow WJ, Ward JK, Krinsky WL.Acute neurologic disease associated with intracranial migration of a first instar larva of a warble fly, Hypoderma bovis (Linnaeus), was observed in a 14-year-old Quarter Horse gelding in western Montana. The disease was characterized by incoordination of gait, circling to the left, head tilt to the right, partial paralysis of the right side of the face, and impaired vision in the right eye. Two and one-half hours after it was first noticed sick, the horse collapsed and was euthanized. Massive hemorrhage unaccompanied by necrosis or significant cellular response was present in the right side o...
Motton DD, Roser JF.Recent evidence in our laboratory suggests that the cause of idiopathic subfertility/infertility in breeding stallions may originate in the testes at the luteinizing hormone (LH) receptor or postreceptor level. The objective of this research was to determine if LH receptor binding activity is altered in subfertile and infertile stallions. Six fertile, three subfertile, and three infertile stallions, ages 11-23 years, were classified according to normal semen parameters and pregnancy rates and then castrated in the breeding season. Blood was collected prior to castration, and plasma was stored ...
Hurtgen JP, Ganjam VK.Endometrial biopsy or endometrial biopsy and uterine culture taken on Day 4 after oestrus induced lysis of the corpus luteum (CL), resulting in a sharp decline in serum progesterone concentration and shortened the interoestrous interval in 8/12 and 32/33 oestrous cycles, respectively, during 2 experiments. Cervical dilatation 4 days after oestrus shortened the interoestrus interval in 5/10 and 0/5 oestrous cycles. Endometrial biopsy and culture on Days 1 and 3 after oestrus also induced CL lysis during 4 of 7 cycles. Total oestrogen (oestrone plus oestradiol) concentrations increased at the on...