Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Veterinary Research
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.
Studies on equine recurrent uveitis. II: The role of infection with Leptospira interrogans serovar pomona. An enzyme linked immunosorbent assay was developed for the detection of immunoglobulin class specific antibodies to Leptospira interrogans serovar pomona in the serum and aqueous humor of horses. Serum antibody was also assayed by microscopic agglutination tests. Although higher levels of antibody were found in sera from horses with signs of uveitis, the association was not statistically significant. Antibodies to pomona were detected in the aqueous of 12 eyes from the 101 horses sampled at a slaughterhouse, and in most instances, a comparison of the aqueous/serum antibody level with that of t...
Inhibitory effects of intravenous chloramphenicol sodium succinate on the disposition of phenylbutazone in horses. The effects of i.v. chloramphenicol sodium succinate on the pharmacokinetics of i.v. phenylbutazone in six healthy adult horses were investigated. Administration of chloramphenicol sodium succinate to mares reduced mean (+/- SD) phenylbutazone clearance from 0.600 +/- 0.222 to 0.339 +/- 0.123 ml/min per kg and increased mean (+/- SD) half life from 244 +/- 59.8 to 371 +/- 80.8 min and mean residence time from 333 +/- 86.2 to 533 +/- 124 min. The mean steady-state volume of distribution of phenylbutazone was unchanged, with mean (+/- SD) values of 187 +/- 28.9 ml/kg in control animals and 170 +...
Chemical immobilization and blood analysis of feral horses (Equus caballus). Combinations of etorphine hydrochloride and xylazine hydrochloride in different dosages were tested for their efficacy as immobilizing agents on 16 recently captured feral mares in corrals. The results of these trials led to the utilization of a standard combination of 5.5 mg of etorphine hydrochloride, 150 mg of xylazine hydrochloride, and 3 mg of atropine sulfate in a 7-ml dart syringe for field capture. This combination was used, administered by dart gun from helicopters, to capture 87 free-ranging feral horses from about 80 bands. Five mares died at the time of capture and the remains of t...
Enhanced biliary bilirubin excretion after heparin-induced erythrocyte mass depletion. The effect of large-dose heparin therapy on erythrocyte mass depletion in ponies was investigated to determine whether stimulation of reticuloendothelial cell activity and catabolic function would be evidenced by enhanced catabolism of heme to bilirubin. Ponies with chronic external biliary fistula were used to examine biliary excretion of bilirubin both before and after heparin loading (107 U/kg, IV, plus 320 U/kg, subcutaneously) and at maintenance dosages of 320 U/kg given (subcutaneously) at 12 and 24 hours after initial loading with heparin. Results indicated that by 48 hours after ponies...
Healing of surgically created defects in the equine superficial digital flexor tendon: collagen-type transformation and tissue morphologic reorganization. Full-thickness defects were surgically created in the superficial digital flexor tendons of the front limbs of 20 horses. Tissues formed within the defect were evaluated histologically, and the collagen composition of the tissue was determined by immunofluorescence. Transformation occurred from loose fibrillar areas of types I and III collagen and pericellular types IV and V collagen to dense bundles of type I collagen fibers. Loose fibrillar areas of types I and III collagen were present after 24 weeks. Histologically, in horses killed after 2 weeks, the tissue within the defect was a randoml...
Enzyme-linked immunosorbent assay for diagnosis of Corynebacterium (Rhodococcus) equi infection in foals. An enzyme-linked immunosorbent assay (ELISA) was used to diagnose Corynebacterium (Rhodococcus) equi infection in foals. In tests done with different antigen-extraction procedures (sodium dodecyl sulfate, sodium deoxycholate, polyoxy-ethylene [9] p-tert-octylphenol, polyoxy-ethylene [9-10] p-tert-octylphenol, sonification, homogenization, and heat treatment at 121 C), Tween 20 was a satisfactory reactive antigen. Using hyperimmune rabbit sera or infected foal sera, we investigated the specificity and the sensitivity of the ELISA with the Tween 20 antigen of the different serotypes or of the is...
Anaerobic bacteria in 21 horses with pleuropneumonia. Anaerobic bacteria are important and overlooked bacterial pathogens of the lower respiratory tract in horses. Twenty-one of 46 horses with pleuropneumonia had anaerobic bacteria isolated from pleural fluid or from tracheobronchial aspirate. Bacteroides oralis and B melaninogenicus were the anaerobes most frequently isolated. Survival was significantly less for horses from which anaerobes were isolated than for horses from which anaerobes were not isolated. Putrid odor was associated with the pleural fluid and/or breath in 62% of the horses from which anaerobes were isolated. In these horses, t...
[Periodic uveitis in horses]. The aetiology, clinical symptoms and treatment of equine periodic ophthalmia are discussed. Particular attention is paid to the possible role in aetiology of Onchocerca cervicalis microfilariae. Corticosteroids and atropine are the most important therapeutic drugs.
Effect of upper airway CO2 on breathing in awake ponies. We determined whether the [CO2] in the upper airways (UA) can influence breathing in ponies and whether UA [CO2] contributes to the attenuation of a thermal tachypnea during periods of elevated inspired CO2. Six ponies were studied 1 mo after chronic tracheostomies were created. For one protocol the ponies were breathing room air through a cuffed endotracheal tube. Another smaller tube was placed in the tracheostomy and directed up the airway. By use of this tube, a pump, and prepared gas mixtures, UA [CO2] was altered without affecting alveolar or arterial PCO2. When the ponies were at a neut...
Pharmacokinetics and bioavailability of cephalothin in horse mares. The pharmacokinetics and bioavailability of cephalothin given to 6 horse mares at a dosage level of 11 mg/kg of body weight IV or IM were investigated. The disposition of cephalothin given IV was characterized by a rapid disposition phase with a mean half-life of 2.89 minutes and a subsequent slower elimination phase with a mean half-life of only 14.7 minutes. The mean residence time of cephalothin was 10.6 +/- 2.11 minutes. The total plasma clearance of cephalothin averaged 13.6 ml/min/kg and was caused by metabolism and renal elimination. Renal clearance of cephalothin averaged 1.32 ml/min/k...
Effect of intrauterine infusion of Escherichia coli endotoxin in postpartum pony mares. Fifteen pony mares were assigned to 1 of 3 treatment groups after foaling: Group 1, 35 ml of sterile saline solution was infused into the uterine lumen within 24 hours after parturition (6 mares); group 2, 300 mg of Escherichia coli endotoxin was infused into the uterine lumen within 24 hours after parturition (6 mares); and group 3, 300 mg of E coli endotoxin was infused into the uterine lumen between 72 and 96 hours after parturition (3 mares). Rectal temperatures were taken at -1, -0.5, 0, 0.5, 1, 1.5, 2, 3, 4, and 5 hours after treatment. Venous blood samples were also taken at these times...
Isolation of non-O1 Vibrio cholerae associated with enteric disease of herbivores in western Colorado. Non-O1 Vibrio cholerae was isolated from a horse (Equus caballus), a lamb (genus Ovis), and two American buffalo (Bison bison) suffering from enteric disease in the western part of Colorado. In 1981, a foal died of apparent respiratory failure. Necropsy findings included heart failure and gastroenteritis. V. cholerae serovar 347 (Smith) was isolated from the colon of this animal. V. cholerae serovar 27 (Smith) was isolated in 1983 from the intestine of a feedlot lamb suffering from pneumonia and severe watery diarrhea. In 1984, an enteric disease occurred in a herd of American bison. The sick ...
Horse kidney neutral alpha-D-glucosidase: purification of the detergent-solubilized enzyme; comparison with the proteinase-solubilized forms. Neutral alpha-D-glucosidase (alpha-D-glucoside glucohydrolase, EC 3.2.1.20) from horse kidney brush-border membranes was solubilized using Emulphogene BC 720 and purified by an affinity chromatography technique. The enzyme preparation (390-fold purified), which was free of other known microvillus hydrolases, exhibited one precipitate line in crossed immunoelectrophoresis and migrated as a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Several criteria (charge-shift crossed immunoelectrophoresis and hydrophobic chromatography) revealed the purified detergent form of t...
Cell synchronization and dynamic G-banding of equine chromosomes by bromodeoxyuridine. Both dynamic G-banding and cell synchronization produced by bromodeoxyuridine (BrdU), were applied to equine chromosomes. BrdU incorporated during the first half of the S-phase is taken up into the R-bands that are early replicating. These bands, which have incorporated BrdU, cannot contract as usual and remain elongated; only the other regions of the chromosome, i.e., the G-bands, contract normally and are sharply defined. BrdU also can be used for cell synchronization. The addition of BrdU in a high concentration, 15 hours before harvest, and its removal 11 hours later, has two effects: init...
Hormonal response to thyrotropin-releasing hormone in healthy horses and in horses with pituitary adenoma. Cortisol, triiodothyronine (T3), thyroxine (T4), insulin, and glucose responses to thyrotropin-releasing hormone (TRH) were evaluated in 12 healthy, mature horses and in 7 horses and 4 ponies with clinical signs of pituitary adenoma (PA). Within 1 hour after TRH administration, the increase in T3 and T4 was similar in healthy horses and animals with PA. Plasma cortisol in the group with PA increased (P less than 0.05) within 0.25 hours after TRH administration, and remained increased for 1.5 hours. In the control group, a significant increase in plasma cortisol concentrations did not develop a...
Role of hilar nerve afferents in hyperpnea of exercise. The objective of this study was to determine the role of hilar nerve (lung vagal) afferents in the hyperpnea of exercise. Ten ponies were studied before and 2-4 wk and 3-12 mo after sectioning only the hilar branches of the vagus nerves (HND). After HND, lung volume feedback to the medullary centers was attenuated as indicated in the anesthetized state by 1) attenuation or absence of the Hering-Breuer inflation reflex (P less than 0.01) and 2) attenuation of the lengthened inspiratory time (TI) when the airway was occluded at end expiration (P less than 0.01). Moreover, after HND in the awake ...
Cardiovascular and respiratory effects of acetylpromazine and xylazine on halothane-anesthetized horses. Circulatory and respiratory effects of intravenously administered acetylpromazine (0.033 and 0.067 mg/kg) and xylazine (0.5 and 1.0 mg/kg) were studied in drug cross-over fashion in eight laterally recumbent horses anesthetized only with halothane (1.06%, end-tidal) in O2. Both doses of acetylpromazine caused a significant and sustained elevation in cardiac output via a rise in stroke volume. Xylazine produced an initial significant fall in cardiac output followed by a return to control levels. Halothane anesthesia did not prevent xylazine-related atrioventricular conduction block. All treatme...
Experimental reactivation of equid herpesvirus 1 (EHV 1) following the administration of corticosteroids. Eight ponies were experimentally infected with equid herpesvirus 1 (EHV 1) (subtype 1). All animals showed clinical and serological evidence of infection and virus was isolated from nasal swabs and leucocytes. These ponies were kept in isolation for a further three months during which time complement fixing antibody decreased at least four-fold. Following immunosuppression with dexamethasone and prednisolone subtype 1 virus was recovered from six of the eight animals within 14 days. Five of these six ponies were viraemic and three of them shed virus in nasal secretions; only four displayed sig...
Isolation of equine coital exanthema virus (equine herpesvirus 3) from the nostril of a foal. The virus causing equine coital exanthema (equine herpesvirus 3) was isolated from a lesion on the nostril of a 2-month-old foal. One week after the mare had returned from a stallion station, vesicular lesions developed on her vulva. They were diagnosed clinically as coital exanthema, and 5 days later a lesion developed on the nostril of her foal. This case is an example of horse-to-horse transmission of coital exanthema virus without coitus. A laboratory diagnosis is necessary to differentiate viruses that cause vesicular lesions about the oral and nasal cavities of horses.
Combined pharmacokinetics of gentamicin in pony mares after a single intravenous and intramuscular administration. Healthy mature pony mares (n = 6) were given a single dose of gentamicin (5 mg/kg of body weight) IV or IM 8 days apart. Venous blood samples were collected at 0, 5, 10, 20, 30, and 45 minutes and at 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12, 18, 24, 30, 36, 40, and 48 hours after IV injection of gentamicin, and at 10, 20, 30, and 45 minutes and at 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12, 18, 24, and 30 hours after IM injection of gentamicin. Gentamicin serum concentration was determined by a liquid-phase radioimmunoassay. The combined data of IV and IM treatments were analyzed by a nonlinear least-square...
Incorporation of L-75Se-cystine in tissue fragments from the matrix of the hoof and the claw–a tool for studying the pathogenesis of laminitis? An in vitro method has been designed and used to study the incorporation of 75Se-cystine into matrix fragments from hooves and claws of healthy horses and cattle. Tissue fragments from the zone of keratinisation were incubated with L-75Se-cystine in a tissue culture medium for 4 to 6 h, during which time there was continuous incorporation of the labelled selenocystine. The incorporation was greatly decreased by adding L-cystine to the incubation mixture. It is concluded that the incorporation of 75Se-cystine depends on the presence of a specific receptor for cystine in the tissue fragments stu...
Inherited nuclear cataracts in the Morgan horse. Congenital cataracts affecting the fetal and embryonal lens nucleus were found in 12 Morgan horses. Ten of the 12 affected animals were sired by the same stallion and the condition also affected his female half sibling. Although females were almost three times more likely to be affected than males (9 vs 3), the difference was not significant. The ratio of 11 normal to 10 affected offspring by the affected stallion is compatible with an autosomal dominant mode of inheritance.
Equine blood serum calcium and phosphorus concentrations in progressive nutritional hyperparathyroidism. Weekly blood serum samples from 20 yearling horses, divided into equal groups, receiving diets with total calcium to inorganic phosphorus ratios of 1,5/1 and 0,2/1, were analysed for calcium and phosphorus concentrations. This was done over a continuous 23 week period, divided into 2 sub-periods of 16 and 7 weeks each. During the first period complete diets were provided ad lib but were restricted during the second period to accentuate any effects of calcium deficiency and phosphorus excess. Falling calcium levels and rising phosphorus levels during period 1 and a reverse trend during period 2...
