Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Van Beek H, Baars AJ.Metallothioneins (MTs) were separated and quantitated by reversed-phase high-performance liquid chromatography (RP-HPLC), in direct combination with atomic absorption spectrometry (AAS) for quantitation of the metal contents in MTs. MTs were eluted from an RP-8 column with a gradient of Tris buffer pH 7.0 and methanol, and were detected by UV absorbance (220 nm). Commercially available purified MTs from horse kidney and rabbit liver were analyzed for purity and metal composition. One lot of horse kidney yielded only 50% of the estimated value. In some cases, the certified metal content differe...
Pycock JF, Allen WE, Porter DJ, Boyd EH.Two independent assay systems were used to study the effect of three antibacterial preparations on in vitro morphology and chemotaxis of equine neutrophils. Incubation of neutrophils with high (200 micrograms/ml) and medium (20 micrograms/ml) concentrations of neomycin impaired their response to standard chemoattractants. Trimethoprim/sulfadoxine (0.4/2.0 micrograms/ml-40/200 micrograms/ml) and benzylpenicillin (0.25-25 micrograms/ml) had no effect. Neutrophils collected from geldings 2 and 24 h after neomycin (5 mg/kg) administration had impaired responses to standard chemoattractants. Benzyl...
Ihrke PJ, Wong A, Stannard AA, Vivrette SL.The fungal flora of the hair and underlying skin from 2 sites was examined qualitatively in 20 horses free of skin or ocular disease. Fungi were isolated from both the hair and the underlying skin of all 20 horses. Twenty-two genera regarded commonly as saprophytes were identified and an additional 2 fungi resembled the perfect state of the cutaneous pathogenic genera Microsporum and Trichophyton. Cladosporium spp, Penicillium spp, and Rhizopus spp were the most frequently isolated saprophytes. In general, similar fungi were isolated from the hair and underlying skin, and differences were not ...
Williamson CC, Stoltsz WH, Mattheus A, Schiele GJ.The complement fixation test (CFT), indirect fluorescent antibody test (IFAT), card agglutination test for trypanosomiasis (CATT) and enzyme-linked immunosorbent assay (ELISA) were compared in their application to the serological diagnosis of Trypanosoma equiperdum infection in 43 horses. The CFT remains a reliable test for dourine, especially in countries where other members of the subgenus Trypanozoon do not occur. The IFAT is a good 'back-up' test, but, requiring skilled operators it has the disadvantage of making it labour intensive, and interpretation of results subjective. This makes it ...
Folz SD, Pax RA, Klei TR, Thomas EM, Ash KA, Conder GA, Bennett JL.An in vitro assay involving the use of a horse strongyle (Strongylus edentatus) and the micromotility meter has been developed to test for equine anthelmintic activity. Three commercially available equine anthelmintics (dichlorvos, ivermectin, and pyrantel pamoate) and an investigational drug (p-toluoyl chloride phenylhydrazone) were evaluated in this assay at four concentrations. After a 24-h incubation, greater than or equal to 10 micrograms/ml of all four drug treatments significantly (P less than or equal to 0.05) reduced the motility of ensheathed L-3 S. edentatus larvae, thereby indicati...
Lehrman SR, Lahm HW, Miedel MC, Hulmes JD, Li CH.Equine prolactin was determined to be a single chain protein of 199 amino acid containing two tryptophan and six cysteine residues, as found in other mammalian prolactins. The primary sequence of equine prolactin was obtained by automated Edman analyses of S-carboxymethylated protein and proteolytic fragments of modified protein. Of the known prolactin sequences, equine prolactin shows closest homology with porcine (93%) and fin whale (87-91%) prolactins. Genetic mutations have produced changes in 17 of 199 residues of equine prolactin relative to its putative ancestral precursor. Since equine...
Snyder JR, Olander HJ, Pascoe JR, Holland M, Kurpershoek CJ.Morphologic changes that develop sequentially in the large colon during experimentally induced ischemia were documented in 14 halothane-anesthetized horses. Colonic ischemia was induced by 4 types of vascular occlusion, 24 cm proximal and distal to the pelvic flexure. The effect of transmural (colonic wall) vascular compression combined with either venous occlusion (3 horses, group A) or venous and arterial occlusion (3 horses, group B) of the colonic vessels was studied for 1, 2, and 6 hours of occlusion. Also observed was the effect of reperfusion for 0.5 hour after release of the clamps for...
Kotzé SH.The muscle layers of the ileocaecal junctions of horses (n = 18), plains zebras (Equus burchelli antiquorum) (n = 3), mountain zebras (Equus zebra zebra) (n = 2), and a donkey were examined macroscopically and microscopically. The muscular tunic of the ileocaecal papilla was made up of 3 layers: an innermost circular layer which was a continuation of the circular muscle of the ileum, a central longitudinal layer which was a continuation of one part of the longitudinal layer of the ileum and an outermost layer, composed of two collateral semicircular lips, formed by the circular layer of the ca...
Traub-Dargatz JL, Gay CC, Evermann JF, Ward AC, Zeglen ME, Gallina AM, Salman MD.Epidemiologic and etiologic data about diarrhea in foals were collected under a planned prospective recording and monitoring study. The survey and monitoring procedures included a survey to obtain an overview of current horse management practices on participating farms, a daily health record survey to obtain information on mares and their foals, and collection of feces from 19 of 144 diarrheic foals and 10 age-matched nondiarrheic foals for electron microscopy, ELISA for rotavirus, and bacteriologic culture. Coronavirus was detected in the feces of diarrheic as well as clinically normal foals....
Qureshi GA, Eriksson A.A method for the routine determination of the beta-adrenergic drugs clenbuterol and mabuterol in equine plasma has been developed. The drugs were isolated from alkalinized plasma by liquid-liquid extraction. The organic phase was evaporated to dryness and the residue was dissolved in the mobile phase prior to injection. The recoveries were 98% and 95% for clenbuterol and mabuterol, respectively. The drugs were separated by reversed-phase high-performance liquid chromatography and quantitated by a use of a coulometric detector set at +0.75 V vs. the internal reference electrode. The influence o...
Johansson M, Anlér EL.A quantitative method for the analysis of flunixin, 2-(2-methyl-3-trifluoromethylanilino) nicotinic acid, in equine urine by gas chromatography with nitrogen-phosphorus detection has been developed. Flunixin and the internal standard, mefenamic acid, N-(2,3-xylyl) anthranilic acid, were analysed after extractive methylation of the carboxylic acid group using methyl iodide. The extraction and alkylation conditions of flunixin and mefenamic acid have been studied. The detection limit of the method was 0.25 mumol/l flunixin in urine (74 ng/ml). Flunixin was found to be conjugated to 96.5% in equi...
West HJ.Single intravenous injections of bromosulphthalein (BSP) were given to horses and the change in plasma concentration of BSP with time was analysed by computer to obtain the proportionality transfer constants 'a', 'h' and 'b'. No age, weight or sex differences in BSP clearance were found in normal horses. The technique was non-invasive, repeatable and suitable for conscious animals. The measurement of the transfer constants 'a', 'h' and 'b', helped to provide an accurate guide to diagnosis and prognosis of liver disease.
Moorman GH, van Noort JH, Németh F, Breukink HJ, Gootjes P, Verzijlenberg F.A method for detection of neurectomy by electrical stimulation of the skin, distal to the neurectomy site, was tested for accuracy and feasibility. An electrical stimulation device was designed and tested to find the minimum peak voltage that would elicit a response in normal horses. Twenty seven horses were then tested at regular intervals following neurectomy and their responses recorded. Immediately following neurectomy there was an area of insensitivity with sharply defined borders extending in an arc from the back of the pastern down towards the bulbs of the heels. In the months following...
Stokes A, Wardley RC.Immunity to equine herpesvirus type 1 (EHV-1) was evaluated using sera collected from yearling horses involved in a trial of a commercial vaccine. Measurement of the ability of these sera to mediate antibody-dependent cellular cytotoxicity and complement-dependent lysis revealed that these mechanisms, although potentially important in recovery from EHV-1 infection, do not play a role in protection following vaccination.
Watney GC, Hall LW, Jordan C, Nolan AM.The effects of xylazine (an alpha 2-adrenoceptor agonist) and acepromazine (an alpha-adrenoceptor antagonist) on bronchomotor tone were investigated in seven anaesthetised, apnoeic ponies using a computer aided forced oscillation technique, which separates changes in bronchial calibre from changes in lung volume. Both agents produced bronchodilatation and a decrease in lung volume.
Cook RF, Sinclair R, Mumford JA.An antigen capture indirect enzyme linked immunosorbent assay (ELISA) was developed to detect influenza nucleoprotein antigen in nasal secretions from horses infected with A/equine/H3N8 viruses. Results from this assay were compared with conventional virus isolation in embryonated hens eggs.
Bertone JJ.Six standing awake adult horses were instrumented for measurement of mean arterial, central venous, and pulmonary arterial blood pressures (mm of Hg), thermodilution cardiac output (ml/kg/min), and pulmonary arterial blood temperature (C). Total peripheral resistance was calculated from these values. Base-line data were accumulated, and a single dose of hydralazine HCl (0.5 mg/kg) was administered IV. Horses were monitored for 420 minutes after hydralazine administration. Mean arterial and central venous blood pressures did not change from the base-line values. Cardiac output and heart rate we...
Tai CL, Wang C, Weckman TJ, Popot MA, Woods WE, Yang JM, Blake J, Tai HH, Tobin T.To improve the sensitivity and specificity of screening for etorphine in horses, an 125I-labeled etorphine analog was synthesized and an antibody to etorphine was raised in rabbits. A radioimmunoassay (RIA) for etorphine was developed, using these reagents. Bound and free 125I-labeled etorphine was separated by a double-antibody method that reduced interference from materials associated with equine urine. The 125I-labeled etorphine binding was rarely greater than 250 pg of background etorphine equivalents/ml in raw urine and was 100 pg/ml in hydrolyzed urine. The 125I-RIA was capable of detect...
Watson ED, Stokes CR, Bourne FJ.Prostaglandins (PGs) F and E2 were measured in lavage fluid from the uterus of ovariectomised mares after experimental induction of uterine inflammation. Treatment with progesterone alone, or progesterone followed by oestradiol, significantly increased the concentrations of these PGs in the lavage compared with mares treated with oestradiol or control mares. Ovarian steroids, therefore, influenced uterine PG synthesis in response to an inflammatory stimulus. To determine whether the uterine lavage procedure might contribute to the concentrations of prostaglandins in the lavage, the procedure w...
Enders AC, Lantz KC, Liu IK, Schlafke S.Twelve blastocysts, collected 7-12 days after ovulation (Day 0), were examined by light and electron microscopy to investigate the nature of the relationship of the polar trophoblast (Rauber's layer) to the inner cell mass. On Day 7, the polar trophoblast was intact and formed a flattened layer overlying the epiblast cells of the inner cell mass. As blastocysts enlarged to greater than 1 mm in diameter, small discontinuities appeared in the polar trophoblast, where epiblast cells intruded onto the surface. At this time, trophoblast cells adhered closely to adjacent and underlying epiblast cell...
Lloyd KC, Stover SM, Pascoe JR, Baggot JD, Kurpershoek C, Hietala S.The concentration of gentamicin in plasma and synovial fluid of normal adult horses was measured periodically for 24 hours after IV (2.2 mg/kg of body weight), intra-articular (IA; 150 mg), and simultaneous IV and IA administrations. Gentamicin also was buffered with sodium bicarbonate (3 mEq) and then was administered IA and simultaneously IV and IA. Synovial fluid specimens were obtained via an indwelling catheter placed into the antebrachiocarpal joint. The peak mean plasma gentamicin concentration (8.30 micrograms/ml) after IV administration was significantly (P less than 0.05) greater tha...
van Weeren PR, van den Bogert AJ, Barneveld A.A technique enabling simultaneous visualisation of skin and underlying bony structures in the walking horse was used to quantify skin displacements on the lateral surface of carpal, tarsal and fetlock joints. The technique employed implanted light-emitting-diodes (LEDs) for marking the bone, and self adhesive spot labels for marking the overlying skin. Photographic recordings were made. Skin displacement was measured in six Dutch Warmblood horses. Mean total displacements and mean displacement per degree of change of joint angle were calculated. Displacements at the level of the fetlock joints...
Lloyd KC, Stover SM, Pascoe JR, Pool RR, Kurpershoek C.The effect of gentamicin sulfate, unbuffered and buffered with sodium bicarbonate, on synovial fluid and membrane of clinically normal equine joints was evaluated. Thirty-six adult horses with clinically normal antebrachiocarpal joints were allotted to 6 treatment groups of 6 horses each. One antebrachiocarpal joint in each horse was chosen for treatment. Group-1 horses were given gentamicin (3 ml; 50 mg/ml); group-2 horses were given sodium bicarbonate (3 ml; 1 mEq/ml); group-3 horses were given gentamicin (3 ml; 50 mg/ml) and sodium bicarbonate (3 ml; 1 mEq/ml); group-4 horses were not treat...
Araújo-Viel MS, Juliano MA, Oliveira L, Prado ES.The effect of secondary-subsite interactions on the catalytic efficiency of horse urinary kallikrein was studied using as substrates oligopeptides and peptidyl-4-nitroanilides with L-Arg at P1. The known secondary specificity of tissue kallikreins for hydrophobic residues at P2 was also demonstrated for horse urinary kallikrein and a higher preference of this enzyme for L-Phe over L-Leu at P2 was evident. Interaction of subsites S3 with D-Pro and D-Phe enhanced the catalytic efficiency but tripeptidyl-4-nitroanilides with acetyl-D-Pro, L-Pro and acetyl-L-Pro at P3 were no better substrates tha...
Clay CM, Squires EL, Amann RP, Nett TM.Influence of day length on seasonal endocrine responses were studied using stallions (seven per group). Treatments included 1) control, with natural day length; 2) 8 h light and 16 h dark (8:16) for 20 wk beginning July 16, 1982 then 16:8 from December 2, 1982 until March 5, 1984 (S-L); or 3) 8:16 from July 16, 1982 until March 5, 1984 (S-S). Blood was sampled hourly for 5 h every 4 wk; sera were pooled within horse, and luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone were quantified. Blood was collected every 20 min for 24 h every 8 wk and 2 wk before and after t...
Gentry PA, Woodbury FR, Black WD.The clotting times obtained with different assay procedures for routine coagulation tests were examined for horse and pony samples. The whole blood clotting time test and the activated coagulation test seemed to give similar results when both tests were done at 22 C. The results obtained for the activated partial thromboplastin time assay varied, depending on the commercial reagent used for the test. Consistent results were obtained for the one-stage prothrombin time assay with each reagent used.
Anderson D, Kollias-Baker C, Colahan P, Keene RO, Lynn RC, Hepler DI.The liposomal cream formulation of diclofenac, an NSAID, is an effective, safe, and convenient way to treat localized areas of inflammation in horses. The results of this study reveal urinary and serum concentrations of diclofenac following topical administration of 1% liposomal diclofenac cream for 10 days at the labeled dose and at 2X and 4X the labeled dose. These results demonstrate the slow absorption and elimination of 1% liposomal diclofenac cream and may be useful when estimating the withdrawal time needed before a competition in order to prevent an inadvertent positive drug test.
Tranquille CA, Dyson SJ, Blunden AS, Collins SN, Parkin TD, Goodship AE, Murray RC.To determine whether histopathologic characteristics of the osteochondral units of equine distal tarsal joints were associated with exercise history in horses without lameness. Methods: 30 cadaver tarsi from horses without lameness and with known exercise history were separated into 3 groups: nonridden, pasture exercise (group P); low-intensity, ridden exercise (group L); and high-intensity, elite competition exercise (group E). Methods: Standardized sites from the centrodistal and tarsometatarsal joints under went histologic preparation. A grading system was adapted to describe location, dept...
Guan F, You Y, Fay S, Adreance MA, McGoldrick LK, Robinson MA.Doping control is essential for sports, and untargeted detection of doping agents (UDDA) is the holy grail for anti-doping strategies. The present study examined major factors impacting UDDA with metabolomic data processing, including the use of blank samples, signal-to-noise ratio thresholds, and the minimum chromatographic peak intensity. Contrary to data processing in metabolomics studies, both blank sample use (either blank solvent or plasma) and marking of background compounds were found to be unnecessary for UDDA in biological samples, the first such report to the authors' knowledge. The...