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.
Gay CC, Lording PM.Actinobacillus equuli was the cause of peritonitis in 5 horses. In 3 the onset was sudden with intestinal stasis and acute abdominal pain as predominant findings. Two others presented with chronic disease and weight loss. Characteristically the peritoneal fluid had a high nucleated cell count with non-degenerate neutrophils as the predominant cell type. Four horses were treated and recovered.
Perryman LE, Torbeck RL.A 3-year prospective breeding trial was designed to verify the mode of inheritance of combined immunodeficiency (CID) in Arabian horses. Twenty-six mares that had previously produced foals with CID were mated to a stallion that had sired foals with CID. Of 53 foals obtained, 15 (28.3%) had CID. The ratio of female to male foals was 28:25, and the ratio of female CID to male CID foals was 8:7. The results of this trial confirmed a suggestion that CID in Arabian horses is inherited as an autosomal recessive trait.
Merritt AM, Smith DA.The concentrations of acetate (C2), propionate (C3), isobutyrate (iC4), butyrate (nC4), isovalerate (iC5), and valerate (nC5) were measured in the feces of 16 clinically normal horses and 44 horses with chronic diarrhea of at least 1-month's duration. The diarrheal horses were categorized diagnostically as: (1) no discernible clinical abnormalities other than diarrhea and in some cases, weight loss (open); (2) clinical evidence of strongyle larval migrans; and (3) Salmonella organisms recovered from the feces. Osmolarity of the feces of 14 of the normal and 15 of the sick horses also was measu...
Steffey EP, Farver T, Zinkl J, Wheat JD, Meagher DM, Brown MP.Quantitative changes in hematologic and serum biochemical values associated with prolonged general anesthesia produced by known alveolar doses of halothane in oxygen were determined in six young, healthy horses under laboratory conditions. In addition, 25 young equine patients anesthetized for shorter periods under clinical conditions were similarly (except hematologic values) prospectively evaluated. In normal horses, muscle- and hepatic-derived serum biochemical values were mildly increased immediately after anesthesia. Values after anesthesia remained at greater than base-line values for up...
Plopper CG, Mariassy AT, Hill LH.Two morphologic characteristics have been used to define the nonciliated bronchiolar epithelial cell: abundant agranular endoplasmic reticulum (AER) and membrane-bound avoid granules. To assess the ultrastructural homogeneity of this cell type in the lungs of large domestic mammals used as experimental models in pulmonary research, we evaluated lungs of horse, steer, sheep, dog, and cat. Bronchioles of known anatomic location were examined by electron microscopy following fixation by airway infusion at standard pressure and processing by selective embedding techniques. Nonciliated bronchiolar ...
Tinling SP, Cardinet GH, Blythe LL, Cohen M, Vonderfecht SL.The structure of sarcocysts in a horse is presented. Light microscopic examination revealed that the maximum cyst dimensions were 136 X 990 micrometers and the cyst walls were striated and 1 to 3 micrometers thick. Electron microscopic examination revealed that the "cyst wall" was formed by villuslike protrusions of the parasitophorous vacuole's primary wall. A unique feature was the presence and arrangement of microtubules within the parasitophorous vacuole. Thirty-four to 55 microtubules extended from the apical tips and sides of each villus and passed through the ground matrix to form junct...
McGowan JJ, Allen GP, Barnett JM, Gentry GA.Infection of horse KyED cells with equine herpesvirus type 3 (EHV-3) resulted in a sevenfold increase in cytosol deoxythymidine kinase (dTK) activity. The EHV-3 dTK was purified from KyED cytosol dTK by affinity chromatography on deoxythymidine-Sepharose and characterized with respect to its electrophoretic mobility, molecular weight, substrate specificity, phosphate donor specificity, and immunological specificity. The purified EHV-3 dTK migrated in polyacrylamide gels with an Rf of 0.30 and sedimented in glycerol gradients with an S value of 5.13, corresponding to a molecular weight of 83,00...
Benson GJ, Hartsfield SM, Manning JP, Thurmon JC.Succinylcholine chloride administered to horses anesthetized with halothane in oxygen and mechanically ventilated, caused slight but statistically insignificant (P less than 0.01) increases in creatine phosphokinase, lactic dehydrogenase, and aspartate aminotransferase activity. The increases in these enzymes have been explained on the basis of muscle damage resulting from succinylcholine chloride induced muscle fasciculations and by hypoperfusion of tissues due to depression of the cardiovascular system caused by general anesthesia. These changes were not clinically apparent based upon the ab...
Houghton E, Dumasia MC.1. The metabolism of 19-nor[4-14C]testosterone in a thoroughbred horse has been studied and neutral urinary metabolites obtained after enzyme hydrolysis have been investigated by g.l.c.-mass spectrometry. 2. 3-Hydroxyestran-17-one, 17 alpha- and 17 beta-nortestosterone, estrane-3,17-diol (two isomers), 3,16-dihydroxyestran-17-one (two isomers), 3,17-dihydroxyestran-16-one (two isomers) and estrane-3,16,17-triol were identified in the neutral urinary extracts.
Roberts MC, Kelly WR.Granulomatous enteritis was diagnosed in a 4-year-old Standarbred mare suffering from chronic weight loss, depression, dependent oedema but not diarrhoea. There was hypoproteinaemia (hypoalbuminaemia), lymphocytopaenia and neglibible carbohydrate absorption from the small intestine. Pathological changes in almost the entire small intestine included proprial infiltration resulting in partial villous atrophy, and granuloma formation beneath the muscularis which was most severe in the ileum. Slight infiltration occurred in the stomach and the colon. The cells were predominantly lymphocytes and hi...
Williams IF, Heaton A, McCullagh KG.The histological appearance of cells and tissues in the reparative scar tissue which forms in the equine superficial flexor tendon following partial rupture was compared to that of normal tendon. The repair fibroblasts were found to be larger and more basophilic than the tenocytes of normal tendon, to have large vesicular nuclei and to resemble the 'myofibroblasts' described in scar tissue elsewhere. The cell to matrix ratio in scarred zones of tendon was found to be increased and the concentration of collagen in these areas was less than in normal tendon. However, the scar tissue collagen was...
Gabel AA.Since horses ridden at a gallop have a high incidence of bone spavin, and harness horses (Standardbred pacers and trotters) have a different
syndrome, they will be discussed separately. Osteoarthritis (bone spavin) apparently is caused by impact and compression on the distal tarsal
bones, which occurs most forcefully at the gallop (canter). Shear stresses, which occur in the joint between these bones, are most severe at the trot
or pace, and probably cause the usual cunean-tarsitis problem in
Standardbreds. Obviously some of each force occurs at each gait.
Waugh SL, Campbell KB, Klavano PA, Grant BD.A surgical thoracotomy and implantation of an electromagnetic flow probe around the ascending aorta and catheters in the left ventricular (LV) apex of the horse were evaluated. Sixteen operations were done: 4 horses were used for acute experiments, 4 horses died from surgical manipulation, and 8 horses were studied chronically for 18 to 57 days. The electromagnetic flow probe allowed continuous measurement of stroke volume and heart rate. The LV apical catheters, in conjunction with thermal dilution techniques and pressure-sensitive devices, allowed measurement and calculation of mean arterial...
Nitschelm D, van der Horst CJ.The effect of orally administered chlormadinone acetate (CAP), 10 mg daily for a period of 16 days, was investigated in the case of four mares with an irregular oestrous pattern accompanied by low ovarian activity (group 1), four mares which did not show oestrous symptoms at all and which had also low ovarian activity (group 2), and two ovariectomized and two ovario-hysterectomized mares (group 3). In all mares of group 1 and in the two ovariectomized mares of group 3 oestrus symptoms became apparent during treatment. Two mares of group 2 came into heat 8 and 11 days after the cessation of tre...
Kendall A, Mayhew IG, Petrovski K.Treatment of subclinical carriers of Streptococcus equi subsp. equi with a gelatine-penicillin formulation deposited in the guttural pouch has been empirically proposed, but data on local tissue penicillin concentrations after treatment are lacking. Methods: We analysed tissue levels of penicillin after administration into the guttural pouches of four healthy horses. Two horses received local treatment with gelatine-penicillin and two horses received local treatment with an intramammary formulation of penicillin. Tissues were harvested for analysis either 12 or 24 h later. Conclusions: Resul...
Roach J, Arango Sabogal JC, Smith K, Foote A, Verheyen K, de Mestre AM.Risk factors associated with equine reproductive efficiency have been identified along with those associated specifically with early pregnancy loss (EPL). In contrast, no studies have reported risk factors associated with abortion (loss between day 70 and 300 post-cover). Given the causes of abortion differ to those of EPL, likely too will the risk factors. A retrospective cohort study was carried out to identify risk factors associated with abortion in UK and Irish based Thoroughbreds, collecting data on 20 exposure variables over a five-year period. A generalized linear mixed model was utili...
Wakuri H, Sakuma Y, Mutoh K, Watanabe S.In 6 equine specimens of both sexes, the morphological features of the cleavage lines of the skin over the entire body were examined using a metal probe with a sharp conical point. Wounds were produced on the skin with the probe and painted with Chinese white or Indian ink. The direction of running of the cleavage lines was determined from their relationship to the long axis of each region or area of the physical structure. The cleavage lines of the head and face revealed a fixed pattern in all specimens. They were similar to those of equine fetuses of 6 to 7 months of age. A transverse patter...
Weiser MG.Using a single channel electronic cell counter and attached particle size analyzer, leukocyte size distribution histograms were determined on canine, feline, bovine, and equine blood diluted with chloride-based diluent and treated with a conventional stromatolysin. Histograms were usually unimodal, but a few were bimodal. Mean values for mean lysed leukocyte particle volume were 49.2, 51.1, 55.4, and 65.0 fl for canine, feline, equine, and bovine blood, respectively. From inspection of histograms, a lower threshold of 30 fl referenced to latex spheres was interpreted to be appropriate for coun...
Zuffa T, Bennet ED, Parkin TDH.Endurance riding is a popular equestrian sport organised at the international level by the Fédération Équestre Internationale (FEI). The sport involves prolonged exercise at speed over significant distances, which puts a substantial load on equine athletes' musculoskeletal systems and metabolism and contributes to the risk of injuries and other veterinary problems. The FEI employs a system of in-ride veterinary inspections aimed at early detection of such problems and elimination of horses unfit to continue in the ride. To date, risk factors for elimination due to irregular gait or metaboli...
Budras KD, Schiel C, Mülling CK, Patan B.The preparation of hard tissues such as the equine hoof horn for electron microscopic examination is very difficult. In particular the penetration of fixatives and chemicals used during fixation and embedding is a problem. The objective of this study was to find and implement an alternative method enabling the preparation of high-quality thin sections of hoof horn and other hard tissue, which maintains the hard tissue ultrastructure and can be used for immuno-labeling. Compared to commonly used fixation and embedding techniques, the preparation of thin sections from untreated material method s...
Drudge JH, Lyons ET, Tolliver SC.Controlled tests of the efficacy of bot-active compounds, dichlorvos, trichlorfon, trichlorfon butonate, and carbon disulfide on the larvae of Gasterophilus intestinalis and Gasterophilus nasalis during their migratory period in the tissue of the mouth of horses and ponies were completed on experimentally induced and naturally acquired infections. Against the experimental parasitisms in pony foals, the resin-pellet formulation of dichlorvos given on the feed at the dose level of 37 mg/kg, 2 formulations of trichlorfon given by stomach tube at the dose level of 40 mg/kg, another of trichlorfon ...
Charnock LN, Davidson MG, Keys DA, Gilger BC, McMullen RJ.To evaluate the normal refractive state in horses in NCSU and ECMR and determine the prevalence of naturally occurring refractive errors and their association with breed, age, coat color, iris color, sex, and geographic location. Methods: Horses from NCSU (January 2009-November 2012) and ECMR (January 2013-September 2016) underwent ophthalmic examination and streak retinoscopy. Location, color, breed, sex, and iris color were recorded. Gross and net refractive values for each meridian (horizontal and vertical), spherical refraction, astigmatism for both eyes, and anisometry were recorded, and ...
Lyons ET, Tolliver SC, Drudge JH, Swerczek TW, Crowe MW.A total of 89 Thoroughbreds, 14 to 333 days old (born in 1982), were examined at necropsy for certain internal parasites during a 1-year-period, Mar 1, 1982, to Feb 28, 1983. The eyes of 73 of the horses and the cranial mesenteric arteries of 71 were examined. Specific interest was on prevalence of parasites according to month of the year and age of the horses at necropsy. Parasites recovered (first month-last month infected horse found) were as follows: Thelazia lacrymalis (eyes) immature and mature (June - February); Habronema/Draschia (lungs) immature (May - September); Habronema muscae (st...
Fielding CL, Magdesian KG.To evaluate changes in electrolyte concentrations and hydration status that take place in endurance horses prior to the start of a competition and determine whether these changes would be associated with elimination. Methods: 19 horses entered in the 2016 Tevis Cup 100-Miles (160 km) One-Day Western States Trail Ride. Methods: Heparinized blood samples were collected at 5 time points: prior to transport to the ride (T0), during check-in the day before the ride (T1), 1 to 2 hours before the start of the ride (T2), at the 15-km mark (T3), and at the 55-km mark (T4). Packed cell volume and plasma...