Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Disease
The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Abscess on the lateral epicondyle of the humerus as a cause of lameness in a horse. An 18-month-old 450-kg [990-lb] sexually intact male Holsteiner was evaluated for lameness of the left forelimb of 3-months' duration. We were unable to localize the site of lameness, using intra-articular and perineural anesthesia, and radiography of the shoulder and cubital joint (elbow) did not reveal radiographic abnormalities. Nuclear scintigraphy was performed. An increase in radio-isotope uptake was evident at the lateral epicondyle of the left humerus. Radiographs of the region 3 weeks later revealed a 1.5-cm focal lucency surrounded by a 1.0-cm rim of necrotic bone. The lesion was con...
Expression of transforming growth factor-beta 1 in normal and dyschondroplastic articular growth cartilage of the young horse. This study describes the distribution pattern of transforming growth factor-beta 1 (TGF-beta 1) mRNA and protein in normal pre- and post natal growth cartilage and alterations present in lesions of dyschondroplasia (osteochondrosis). TGF-beta 1 expression and immunoreactivity have been investigated by in situ hybridisation and immunolocalisation in the articular/epiphyseal growth cartilage of the lateral trochlear ridge of the distal femur. Cartilage was obtained from 19 normal Thoroughbred horses (5 prenatal and 14 post natal horses) and 15 post natal horses with dyschondroplasia (DCP). TGF-b...
Prospective study of equine colic incidence and mortality. A prospective study of one year was conducted on 31 horse farms to obtain population based estimates of incidence, morbidity and mortality rates of equine colic. Farms with greater than 20 horses were enrolled by randomly selecting horse owners from 2 adjacent counties of Virginia and Maryland. Descriptive information for 1427 horses was collected at the initiation of the study and updated at 3 month intervals. Time on the farm during the study was tabulated for each horse. When colic was reported by the owner, investigators visited the farm to obtain information about the colic. The crude inc...
Clinical trial of moxidectin oral gel in horses. A clinical trial carried out over 98 days was done to evaluate treatment of horses with moxidectin gel for efficacy as measured by (1) reduction in the production of parasite ova post treatment, (2) a comparison of the posttreatment parasite egg count suppression of moxidectin to ivermectin, and (3) assessment of the field safety, animal acceptance of the moxidectin formulation, and the utility of the moxidectin delivery device. One hundred and fifty Standardbred horses with naturally acquired parasite infections were used in the study. Moxidectin had more prolonged and greater suppressive inf...
Infection of bone marrow macrophages by equine infectious anemia virus. To characterize infection of bone marrow-derived macrophages (BMDM) with equine infectious anemia virus (EIAV) by determining virus production, effects on viability, and induction of cytokines. Methods: BMDM obtained from bone marrow of 6 clinically normal adult horses. Methods: BMDM were infected with EIAV at a multiplicity of infection of 8. Cell viability, percentage of cells with detectable viral protein, reverse transcriptase activity, and concentrations of infective virus (focus-forming units/ml), interleukin 6, and tumor necrosis factor-alpha were measured in culture supernatant samples...
Antibodies against equine herpesviruses in free-ranging mountain zebras from Namibia. Twenty-one blood samples of free-ranging mountain zebras (Equus zebra) from Namibia were tested for equine herpesvirus (EHV-1, -2, -3, -4) specific antibodies by immunofluorescence assay (IFA) and neutralization test (NT). Additionally, type-specific nested polymerase chain reactions (nested PCR) were employed for detection of EHV-1, -2 and -4 DNA. Equine herpesvirus-1 antibodies were detected by IFA in all zebras, while only seven serum samples contained EHV-4 IFA antibodies. Sera with high IFA antibodies also were found to neutralize EHV-1 and -4. Furthermore, 20 zebras were EHV-2 seropositi...
Evaluation of a test for identification of Arabian horses heterozygous for the severe combined immunodeficiency trait. To determine whether a recently developed test would correctly identify horses heterozygous for the severe combined immunodeficiency (SCID) trait. Methods: Case series. Methods: 17 healthy Arabian horses that had previously produced foals with SCID, 1 healthy Arabian foal whose dam and sire had produced foals with SCID, 4 foals with SCID, and 1 healthy non-Arabian foal. Methods: DNA was extracted from leukocytes or fibroblasts, amplified by means of polymerase chain reaction, and hybridized with probes specific for the normal and mutant alleles of the catalytic subunit of DNA-dependent protein...
Novel and dynamic evolution of equine infectious anemia virus genomic quasispecies associated with sequential disease cycles in an experimentally infected pony. We have investigated the genetic evolution of three functionally distinct regions of the equine infectious anemia virus (EIAV) genome (env, rev, and long terminal repeat) during recurring febrile episodes in a pony experimentally infected with a well-characterized reference biological clone designated EIAV(PV). Viral populations present in the plasma of an EIAV(PV)-infected pony during sequential febrile episodes (18, 34, 80, 106, and 337 days postinfection) were amplified from viral RNA, analyzed, and compared to the inoculated strain. The comparison of the viral quasispecies showed that the ...
Field examination of the equine patient with nasal discharge. This article describes the field investigation of horses with nasal discharge (serous, purulent, blood and feed). Flow charts on how to evaluate affected horses, and photographs of the examination procedures and of horses affected with nasal discharge are included.
Evaluation of the equine respiratory system using physical examination and endoscopy. Defining respiratory disease is not always easy in the horse because auscultation with accurate interpretation of lung sounds can be difficult. However, performing a thorough physical examination, including rebreathing auscultation and percussion of the thorax and sinuses, is very useful in elucidating the problem. Endoscopic examination of the upper respiratory system is also critical for definitively diagnosing certain conditions.
Cytology of the respiratory tract. Cytology can be a rewarding diagnostic technique in equine practice. The respiratory tract readily lends itself to sampling for cytologic evaluation from the upper to lower regions of the system. This article discusses preservation and staining techniques that will allow the practitioner to present satisfactory samples to the laboratory. General considerations for cytologic analysis are discussed as well as the specific findings for individual disorders of the respiratory tract. The proper use of cytologic findings in conjunction with other diagnostic techniques for the respiratory tract are a...
Poor performance and field evaluation of the respiratory system. A thorough examination of the respiratory system is an important part of the work-up for poor performance in horses. This article provides a systematic approach to field evaluation of horses with poor performance due to respiratory system dysfunction. The information is organized to help the reader evaluate pertinent historical and physical examination findings so that a list of differential diagnoses can be generated. Also, pertinent ancillary diagnostic modalities that can help further characterize and localize causes for respiratory dysfunction in horses presented for poor performance are d...
Use of full cortical allograft to repair a metatarsal fracture in a foal. A 4-month-old Quarter Horse colt was admitted for repair of an open, comminuted fracture of the proximal portions of the diaphyses of the left second, third, and fourth metatarsal bones. Initial repair included internal fixation and cancellous bone graft. However, the third metatarsal bone became infected and failed to heal. After removal of infected portions of the bone, a 5-cm, fullthickness cortical allograft was placed in the defect. Rigid internal fixation provided stability for the allograft and remaining fracture fragments so that the horse was able to bear weight on the second and four...
Comparative studies of ivermectin and moxidectin in the control of naturally acquired cyathostome infections in horses. The control of naturally acquired cyathostome infections in horses by treatments with ivermectin and moxidectin was evaluated in three field studies. In a first study the efficacy of both drugs was assessed in a faecal egg count reduction test. Both ivermectin and moxidectin demonstrated efficacies greater than 99 per cent for up to 60 days after treatment. In a second study, the period required for strongyle eggs to reappear was estimated in horses treated either with ivermectin or moxidectin. For the horses treated with ivermectin the period varied between 10 and approximately 13 weeks, and ...
Genetic analysis of equine methicillin-resistant Staphylococcus aureus by pulsed-field gel electrophoresis. Pulsed-field gel electrophoresis (PFGE) was used to determine genetic relationships among 15 methicillin-resistant Staphylococcus aureus (MRSA) isolates from mares with metritis and from a stallion with dermatitis in Hokkaido. All the 15 isolates showed phage pattern 6/47/54/75, coagulase type IV, and enterotoxin type A. The restriction endonuclease SmaI cut their genomic DNAs into 15 or 16 fragments ranging in size from 8 to 630 kb. Fourteen of the 15 isolates showed the same PFGE pattern, whereas the remaining one appeared to be closely related. The 9 human MRSA isolates showing the same phe...
Hemagglutination with equine arteritis virus. Equine arteritis virus (EAV) grown on RK13 cell cultures was tested for hemagglutination (HA) with erythrocytes from a variety of species at 4 degrees C, room temperature and 37 degrees C. HA was observed at all temperatures with erythrocytes from mouse and chicken but not with those of cattle, horse, rabbit, guinea pig, mongolian gerbil, goose or chick embryo. Chickens showed an individual variation in agglutinability of their erythrocytes, requiring selection of birds to obtain erythrocytes for HA. The HA activity was enhanced by treatment of virus materials with Tween 80 followed by treatme...
Effects of various feeding regimens on the energy balance of equine neonates. To determine the effect of diet on energy intake, loss, and metabolism in foals 2 to 7 days old. Methods: 14 pony foals. Methods: Group-A foals suckled their dams, group-B foals were fed milk replacer, and group-C foals were fed by total parenteral nutrition (TPN). Energy balance studies were performed over 8-hour periods on postpartum days 2, 4, and 7. Results: Mean gross energy (GE) intake of group-A foals increased between days 2 and 7. Approximately 3% of GE was excreted in urine and feces, and energy expenditure remained constant. These foals were in positive energy balance, and mean body...
Hypereosinophilia in a horse with intestinal lymphosarcoma. Paraneoplastic eosinophilia is reported in dogs, cats, and humans. Hypereosinophilia (an eosinophil count greater than 1.5 x 10(9) L) is often associated with metastasis and a poor prognosis. This report describes a case of paraneoplastic hypereosinophilia in a pony. Neoplasia should be included in the differential diagnoses in a horse with eosinophilia.
The equine immune response to endometrial cups. Out of all the areas of comparative immunological study in the horse, the field of reproductive immunology has proven to be one of the most fertile and exciting. Maternal immunological interactions with the fetus involve a set of events which prevent maternal rejection of trophoblastic tissue invading the uterus, and at the same time control this invasion to regulate growth and prevent damage to maternal tissues. Unique features of equine placentation make it exceptionally well-suited to studying these immunological interactions.
Multiple vertebral osteochondrosis in a foal. No abstract available
Failure of lipopolysaccharides to directly trigger the chemiluminescence response of isolated equine polymorphonuclear leukocytes. Divergent results have been reported on the effects of lipopolysaccharides (LPS) on the activation of equine polymorphonuclear leukocytes (PMN). We therefore attempted to determine whether LPS alone can stimulate equine PMN or whether plasma factors are necessary. PMN were isolated from citrated blood on a discontinuous density gradient of Percoll. The luminol (10(-3) mol/L)-enhanced chemiluminescence (CL) of 1.25 x 10(6) cells was measured after addition of Escherichia coli LPS (0.001-10 micrograms/ml) alone or after incubation in autologous plasma (1 h, 37 degrees C). After direct stimulatio...
Flow cytometric method for detecting thiazole orange-positive (reticulated) platelets in thrombocytopenic horses. To evaluate a method for detecting thiazole orange-positive (TO+, reticulated) platelets in equine blood, using flow cytometry. Methods: 16 healthy, equine infectious anemia virus (EIAV)-negative horses and ponies; 9 thrombocytopenic, EIAV-positive horses and ponies; and 2 thrombocytopenic, EIAV-negative horses. Methods: Blood from healthy and thrombocytopenic horses was collected by jugular venipuncture. Appropriate sample requirement and incubation time for the assay were evaluated, using blood anticoagulated with EDTA or sodium citrate, or platelet-rich plasma in sodium citrate. The sample ...
