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.
Riemersma DJ, De Bruyn P.The cross-sectional area, collagen content, dry weight as a percentage of the wet weight and the tendon fibre percentage of the cross-sectional area of the equine hindlimb were determined in the superficial and deep digital flexor tendons and the suspensory ligament at 10, 12 and six sites between tarsus and insertion respectively. The values of each of the four parameters varied between different sites in the same tendon, between different tendons within a horse and between analogous tendons of different horses. Within a tendon the cross-sectional area was inversely proportional to the collag...
Gerring EE, Hunt JM.An experimental model of postoperative ileus was developed in ponies using trauma to, and exposure of, a length of small intestine which gave rise to a reproducible and reversible set of changes in gut activity. This was assessed by recordings of electrical and mechanical activity and by propulsion of spheres from stomach to anus. Activity was depressed, especially in the stomach and colon, and transit was slowed. All drugs given increased electromechanical activity but propranolol was the least effective and did not alter the delayed transit of spheres. Yohimbine was more effective and the ad...
Roberts MC, Argenzio A.Amitraz, atropine, glycopyrrolate and morphine (but not its derivatives, meperidine [pethidine], oxymorphone and butorphanol) produced similar effects on clinically observed intestinal functions and significantly prolonged intestinal transit, as assessed with polyethylene glycol (PEG). However, their mechanisms of action, particularly on intestinal transport (fluid movement), may differ widely. Loperamide appeared to exert a preferential action on intestinal transport rather than motility, as there was no significant delay in PEG transit. The action of amitraz in perturbing smooth muscle coord...
Weiss M, Horzinek MC.In equine dermis cells infected with Berne virus particles were first detected 10 h after infection. Virions were encountered in all parts of the Golgi system and, infrequently, in the rough endoplasmic reticulum. A unique form of budding of preassembled rigid tubular nucleocapsids was demonstrated. Masses of tubular nucleocapsids of a lesser diameter and electron density were prominent in the cytoplasm and the nucleus of infected cells. Within the Golgi system and cytoplasmic cisternae virions appeared as straight or slightly curved rods. Extremely long, aberrant virions (250 nm) were occasio...
Sellers AF, Lowe JE.The large intestine has distinct motility patterns which include non-rhythmic haustral kneading of ingesta and stronger rhythmic retropulsive and propulsive contractions which move ingesta along the tract. A variable site electrical pacemaker exists at the pelvic flexure where the strong rhythmic contractions begin. The large intestine can contract adequately with only the intrinsic nerve supply intact. Neurotransmitters have profound effects on large intestinal activity.
Puotunen-Reinert A.In a retrospective study, the prognostic value and individual merit of seven variables, used in routine examination of colic cases, were tested. The following variables proved to be significant in discriminating between horses which survived and those which died: heart rate (P less than 0.00005), packed cell volume (P less than 0.00005) and intensity of colic signs (P less than 0.0001).
Manohar M.Right atrial, right ventricular, and pulmonary artery pressures, along with change in pleural pressure, were determined with catheter-tipped micromanometers in two groups of ponies at rest, as well as during moderate (trot; heart rate = 180 beats . min-1) and severe (gallop; heart rate = 220 beats . min-1) exercise performed on a treadmill. Group A (n = 8) ponies served as controls, and group B ponies (n = 6) had laryngeal hemiplegia (LH) induced by sectioning the left recurrent laryngeal nerve 20-29 days before the study. It was observed that LH ponies could not gallop for more than 45-90 s. ...
Ahmed H, Chatterjee BP, Kelm S, Schauer R.A sialic acid-specific lectin, scorpin, has been purified to apparent homogeneity from the Indian scorpion Heterometrus granulomanus by affinity chromatography on equine submandibular gland glycopeptides linked to Sepharose and gel filtration on Sephadex G-200. The lectin has a molecular mass of 500 000 Da and was dissociated into single polypeptide chains of 15 000 Da, as determined by SDS gel electrophoresis in the presence of 2-mercaptoethanol. Scorpin is a glycoprotein containing 2.8% sugars. Its specificity was investigated by the inhibition of hemagglutination with various derivatives of...
Garza F, Thompson DL, St George RL, French DD.In Exp. 1, 16 long-term ovariectomized pony mares were used to determine the effects of treatment with estradiol benzoate (EB) and dihydrotestosterone (DHT) benzoate alone, and in combination, on secretion of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in daily blood samples and after three consecutive injections of gonadotropin releasing hormone (GnRH). Administration of EB alone, or in combination with DHT, every other day for 11 d reduced (P less than .05) concentrations of FSH and increased (P less than .05) concentrations of LH in daily blood samples, and increased (P ...
Denkhaus M, Van Amstel S.Non-commercial, endotoxin positive, intravenous fluids as well as a commercially available intravenous fluid were given to clinically normal horses. Endotoxin-positive fluids caused clinical signs attributable to endotoxaemia. Leukopenia, preceded by a fluctuating white cell count, was observed in horses showing clinical signs. The commercial intravenous fluid had no effect on the white cell count or on the clinical state. Precautions to be taken and recommendations are made with regard to the monitoring of horses in which one might be forced to use non-commercial intravenous fluids.
Calisher CH, Mahmud MI, el-Kafrawi AO, Emerson JK, Muth DJ.Paired sera from 28 nonvaccinated horses with serologically confirmed western equine encephalitis (WEE) virus infections were evaluated for immunoglobulin (Ig)M and IgG directed against WEE virus, by use of enzyme immunoassay. Twenty-one of the horses developed greater than or equal to 4-fold increases or decreases in serum IgM titers in paired serum samples, confirming the diagnosis of WEE in these horses. Of the remaining 7 horses, 1 had stable IgM titers, 1 had a 2-fold increase in IgM titer between paired sera, 2 had 2-fold decreases in IgM titer, and for 3 horses adequate volumes were not...
Winder NC, von Fellenberg R.Pulmonary parenchymal tissues from 6 healthy horses and from 9 horses with chronic bronchiolitis were evaluated by use of an indirect immunofluorescent technique. In horses of both groups, the diffuse interstitial immunofluorescence was most intense for immunoglobulin (Ig)G, moderate for IgA, and minimal for IgM. Intensity of fluorescence was increased markedly in diseased lungs exposed to anti-IgA and anti-IgG. Around small bronchi and large bronchioles of healthy horses, IgA-containing cells generally were more numerous than were IgG-Fc fragment (Fc)-containing cells; in small bronchioles, h...
Bell LG, Lowe JE.A questionnaire was designed to determine the incidence of major injuries, severe colic, and acute laminitis in horses at American Horse Shows Association (AHSA) A- and B-rated shows, ie, those shows requiring a veterinarian in attendance. The questionnaire was sent to the show stewards and filled out by the attending veterinarians of the AHSA A- and B-rated shows held from January 1982 to October 1984. Of 2,952 questionnaires sent out, 799 (27%) were completed and returned by veterinarians; 99 of them were discarded because of incomplete or misleading information. The study revealed a low inc...
Smith JE, DeBowes RM, Cipriano JE.Corticosteroid preparation was administered to 7 Shetland Ponies and 10 Quarter Horses. Serum iron concentration increased dramatically for 48 to 72 hours after the steroid treatment, whereas serum iron-binding capacity and serum ferritin concentration did not. An increase in available iron may allow bacteria to proliferate when ponies or horses are stressed or treated inappropriately with corticosteroids.
Pearson EG, Hedstrom OR, Sonn R, Wedam J.A 4-day-old foal died with bloody diarrhea. Using a mouse neutralization test, Clostridium perfringens type C was isolated from intestinal contents, and alpha and beta toxins were identified. About 4 m of the jejunum had severe necrohemorrhagic enteritis. Microscopically, large, rod-shaped, gram-positive bacteria were seen on necrotic intestinal villi by use of Brown and Hopp's stains.
Manohar M.Regional distribution of brain blood flow (radionuclide labelled 15 microns diameter microspheres) and O2 supply were studied in 11 healthy adult grade ponies at rest and during severe exercise (SE) performed on a treadmill (heart rate = 220 +/- 4 beats X min-1; VO2 = 126 +/- 9 ml X min-1 X kg-1). During SE, the mean aortic pressure increased to 169 +/- 4 mm Hg and the pHa, PaCO2 and PaO2 were 7.213 +/- 0.010, 30 +/- 1 mm Hg and 85 +/- 4 mm Hg, respectively. The hemoglobin concentration increased by 59.6% with SE. Whereas blood flow increased in the cerebellar gray matter (96%), pons (39.5%) a...
Lyons ET, Drudge JH, Tolliver SC.The efficacy of 2 injectable formulations of ivermectin, administered intraorally at the dosage of 200 micrograms/kg of body weight, was evaluated against naturally occurring infections by abomasal nematodes in lambs in 2 controlled tests. One test (A) included 17 lambs treated with the equine formulation and 16 nontreated lambs. For the other test (B), 14 lambs were treated with the bovine formulation, and 12 were nontreated. In controlled test A, only mature nematodes were recovered, and removals were 98% to 100% for Haemonchus contortus, Ostertagia circumcincta male, O trifurcata male, Oste...
Gabal MA, Awad YL, Morcos MB, Barakat AM, Malik G.Mycotoxicoses involving horses, rabbits and cattle have been studied. Fusarium tricinctum and T-2 toxin were isolated from all incriminated feedstuffs. Other isolated trichothecenes from the feed included HT-2, verrucarins and roridin. The toxins were separated, identified and quantitated using thin-layer chromatography, gas-liquid chromatography and mass spectrometry. T-2 toxin was detected in amounts varying from 0.5-204 ppm. The contaminated feedstuffs in connection with the affected horses and rabbits, included cereal grains (corn, cornstalks, bran and barley), whereas fescue hay was assoc...
Adeyefa CA.The clinicopathological features and treatment of cases of dermatomycotic infections in horses are reported. Organisms isolated from these cases include Trichophyton mentagrophyte, T. equinum and Micosporum equinum. The Veterinary, medical and economic importance of the disease is discussed.
Weers JG, Maki AH.Triplet-singlet energy transfer has been studied in the complex formed between auramine O (AO) and horse liver alcohol dehydrogenase with optically detected magnetic resonance (ODMR) spectroscopy. The results show that Trp-15 and Tyr residues transfer triplet energy mainly by a trivial process, whereas Trp-314 transfers triplet energy by a Förster process with two observed lifetimes at 77 K of 170 and 50 ms. The different Förster energy-transfer lifetimes are ascribed either to quenching of the two Trp-314 residues of the dimer by a single asymmetrically bound AO or to two distinct conformat...
Stecco R, Paccamonti D, Gutjahr S, Pinto CR, Eilts B.Oxytocin is released in response to teasing during both estrus and diestrus in mares, and at least during estrus, teasing results in an increase in electromyographic activity in the uterus. Exogenous oxytocin causes an increase in intrauterine pressure and prior studies have shown that this response is correlated to the day of the estrous cycle. To determine if teasing causes an increase in intrauterine pressure and if this response varies by day of the cycle, intrauterine pressure was measured while mares were teased with a stallion 2 days before ovulation, on the day ovulation was detected a...
Clark AR.Current economic trends in equine practice are trends of weakness. Most practices, after a decade of double-digit growth, have migrated to survival mode within a few months. Understanding that all regions and disciplines are affected differently, using the Porter five forces model, we can identify changes that must be made in our business models first to survive and then to position ourselves to prosper when the recession ends. If we are to avoid long-term damage to our practices, we must use cost control and work efficiency in addition to price concessions.
Tanaka K, Hiraga A, Takahashi T, Kuwano A, Morrison SE.We applied aluminum hinged shoes (AHSs) to the club foot-associated contracted feet of 11 Thoroughbred yearlings to examine the effects of the shoes on the shape of the hoof and third phalanx (P III). After 3 months of AHS use, the size of the affected hooves increased significantly, reaching the approximate size of the healthy contralateral hooves with respect to the maximum lateral width of the foot, the mean ratio of the bearing border width to the coronary band width, and the mean ratio of the solar surface width to the articular surface width. These results suggest that the AHSs corrected...
Mariën T, Adriaenssen A, Segers L.A modified colon tray to perform large colon evacuations in horses was designed. A funnel-shaped accessory was constructed to create a mechanical separation between the sterile and nonsterile part of the tray. Sterile hooks were used to make a temporary and stabile colostomy. Thirty horses with surgical correction of nonstrangulating large colon obstruction underwent a large colon evacuation with this modified tray. The surgical procedure was uncomplicated and resulted in a positive outcome in 29 horses. This less labour-intensive way to evacuate the large colon results in minor contamination ...
Scholtz M, Guthrie AJ, Fosgate GT, Schulman ML.Population demographics and reproductive performance of Thoroughbred populations have been described, but the most recent assessment of the South African Thoroughbred population was reported two decades ago. Objectives of this study were to report demographic data for selected Thoroughbred breeding populations and to analyse selected mare-level variables in association with foaling outcomes, as predictors of reproductive performance. The National Horseracing Authority of Southern Africa's stud health scheme requires annual screening of Thoroughbred stallions, maiden and barren mares for venere...
Losonsky JM, Kneller SK.Bilateral metacarpophalangeal radiographs of 100 Standardbreds were examined for visualization and location of nutrient foramina of the proximal phalanx. Foramina were located in the dorsal or palmar cortex or were not visible radiographically. Of 100 horses, 45 had bilaterally symmetrical foramina. Left and right proximal phalangeal foramina were asymmetrical in the remaining 55 horses. Of 200 proximal phalangeal foramina (in 100 horses), 78 were in the dorsal cortex, 61 were in the palmar cortex, and 61 were not visible radiographically. A significant (P = 0.05) effect of age or sex could no...
Palmer AC, Leadon DP, Rossdale PD, Jeffcott LB.A neuropathological examination was carried out on the brains of 58 foals. Forty-two were pony foals induced at various periods of gestation from 200 days onwards. Two were pre-viable pony foals delivered by caesarean section and 14 were Thoroughbred foals (one set of twins, two stillborn, five premature, two dysmature, two convulsive and one induced). The only significant pathological change involved intracranial haemorrhage. Subarachnoid haemorrhage occurred in all of 10 pony foals induced before 301 days of gestation and in two pony foals born by caesarean section at 270 and 280 days gestat...
Van Niekerk CH, Morgenthal JC, Starke CJ.Two thoroughbred mares bearing twins as diagnosed by rectal palpation, were subjected to nutritional stress by drastically reducing the daily ration. This resulted in a marked reduction in plasma progestagen levels and the death of either one or both of the twin embryos.
Lyons ET, Drudge JH, Tolliver SC.Thirteen critical tests (n = 11 horses and 2 ponies) and 4 controlled tests (n = 4 donkeys and 6 horses) were performed to evaluate the activity of the experimental macrocyclic lactone compound F28249-alpha against internal parasites of equids. In the critical tests, activity was determined mainly against the large parasites, but 1 critical test also included benzimidazole-resistant small strongyles. In the controlled tests, evaluation of drug activity included large parasites and stomach worms in all 4 tests, and lungworms in 2 tests. The period between treatment and euthanasia was 6 to 9 day...
Mir IA, Kumar B, Taku A, Bhardwaj RK, Bhat MA, Badroo GA.The present study was conducted to determine the prevalence of Rhodococcus equi infection in equines of Jammu and Kashmir, India, and evaluate the zoonotic threat posed by this organism to equine owners and tourists. One hundred and forty-one samples (98 samples from adult animals ≥5 years old and 43 samples from foals less than 6 months old) were collected in duplicate from nasopharyngeal tract of equines for isolation and direct PCR. A total of 12 isolates of R. equi were recovered, of which 9 were from foals and 3 from adult animals. Therefore, the present study recorded prevalence rates ...
Sirois J, Betteridge KJ.To recover intact Day-10.5 to Day-16.5 equine conceptuses (Day 0 = ovulation), a rigid catheter was used for 131 collections from donor mares diagnosed pregnant by ultrasonography. A total of 139 conceptuses were recovered, comprising 124 singletons, six pairs of twins and one set of triplets. Of these, 120 (86%) were intact after the collection, 14 (10%) had collapsed, and in five cases (4%), collapsed trophoblastic membranes were surrounded by an intact capsule. The recovery rate of intact conceptuses ranged from 99% on Days 10.5 to 12.5 to 40% on Day 16.5. More uterine flushes per recovery ...
Marr CM.Echocardiography is an extremely versatile tool for both the equine clinician and physiologist. There are three useful forms of echocardiography, B mode, M mode and Doppler. Together they provide complementary information on cardiac disease and haemodynamic status. B mode is used to image the cardiac chambers, valves, myocardium and pericardium. M mode allows determination of motion of cardiac structures; it is superior to B mode for timing of events and it is used to make precise measurements of the heart. Doppler echocardiography can assess intracardiac blood flow and its velocity. Echocardi...
Aleman M, Lecouteur RA, Nieto JE, Williams DC, Stanke NJ, Shelton GD.Sarcoplasmic masses in humans have been associated with various myopathies, although the significance remains elusive. Similar structures have also been observed in equine muscle. The aim of this study was to determine the frequency of such structures in normal and abnormal equine muscle, and to characterize these structures using histological, histochemical, immunohistochemical, ultrastructural, and morphometric analyses. The histological and histochemical appearance was similar to that of human sarcoplasmic masses with a central or subsarcolemmal distribution. Of interest was a predilection ...