Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Clinical Signs
Clinical signs in horses refer to observable physical or behavioral manifestations that may indicate the presence of disease or injury. These signs can include a range of symptoms such as changes in appetite, alterations in gait, abnormal respiratory patterns, or variations in body temperature. Recognizing clinical signs is an integral part of equine veterinary practice, as they provide initial insights into the health status of the animal. Veterinarians rely on these signs to formulate differential diagnoses and guide further diagnostic testing. This page gathers peer-reviewed research studies and scholarly articles that explore the identification, interpretation, and diagnostic value of clinical signs in equine health management.
Back problems. Historical perspective and clinical indications. This article is presented as an introduction to the complex subject of back pain and its management in horses. It considers some of the historical perspectives and deals with some of the limiting factors when attempting to evaluate back pain. The clinical indications of a back problem are considered, as is the important distinction of primary versus secondary back pain. Finally, a list of considerations capable of causing back pain and impaired performance is included.
Investigations on the ability of clenbuterol hydrochloride to reduce clinical signs and inflammation associated with equine influenza A infection. Twenty-four Quarter Horse and Quarter Horse-cross yearlings were experimentally infected with influenza A virus (Influenza A/equine/Saskatoon/90 [H3N8]) by nebulisation. In a double blind controlled trial the horses were randomly assigned to 3 groups of 8 animals. Group 1 received a placebo, (carrier syrup), Group 2 the labelled dose and Group 3 twice the labelled dose of clenbuterol hydrochloride. All treatments were given per os b.i.d. for 10 days and started on the day of infection. The horses were monitored for clinical signs of influenza infection for 14 days. Bronchoalveolar lavages were...
Use of phenytoin to treat digitalis-induced cardiac arrhythmias in a miniature Shetland pony. Two miniature Shetland ponies showing clinical signs of Digitalis purpurea (foxglove) poisoning were examined. One animal died shortly afterwards, but the second was treated successfully with the anti-arrhythmic agent, phenytoin, and was discharged after 16 days.
Comparison of medical and surgical treatment for impaction of the small colon in horses: 84 cases (1986-1996). To characterize clinical findings and compare effects of treatment and outcome for horses treated medically or surgically for impaction of the small colon. Methods: Retrospective study. Methods: 84 horses with impaction of the small colon. Methods: Medical records were reviewed for history, physical examination findings, laboratory values, treatment, response to treatment, complications, out-come, and necropsy findings. Results: 47 horses were treated medically and 37 horses were treated surgically. Significant differences between groups were not identified for duration of clinical signs, phys...
Hepatotoxicity associated with pyrrolizidine alkaloid (Crotalaria spp) ingestion in a horse on Easter Island. Since 1984, a significant number of privately owned and feral horses on Easter Island have died of a syndrome consisting of progressive anorexia, weight loss, obtundation, and other central nervous system abnormalities. A single horse experiencing clinical signs of the reported syndrome was identified, examined and necropsied. Clinical signs included inappetence, emaciation, ataxia and icterus. Gross necropsy findings included hepatic enlargement and mottling, ascites and gastric impaction. Histopathological lesions included hepatic hemorrhage and necrosis, periportal megalocytosis, portal fib...
Infection with equine herpesvirus 1 (EHV-1) strain HVS25A in pregnant mice. The abortigenic effects of equine herpesvirus 1 (EHV-1) strain HVS25A, given intranasally, were assessed in pregnant BALB/c, C57BL/6J and Quakenbush mice at day 16 of pregnancy. All EHV-1-infected BALB/c mice showed clinical signs typical of EHV-1-induced disease, together with evidence of abortion. However, although there were fetal and neonatal deaths in some C57BL/6J and Quakenbush litters, the respiratory and systemic effects of EHV-1 infection in the dams were inconsistent. BALB/c dams were then inoculated at day 15 of pregnancy with either EHV-1 or rabbit kidney (RK) cell lysate (control...
Prevalence of Surra among camels and horses in Jordan. The prevalence of Trypanosoma evansi infection among camels and horses in Jordan was studied using thick blood smears and inoculation techniques with mice and rats. A total of 437 camels and 83 horses from four climatic zones were surveyed. In addition, 40 donkeys, 32 cattle and 35 goats in contact with infected camels and horses were also tested in the same way. Clinical disease was evident in 8.2% of the camels (36 out of 437) and in 9.6% of the horses (8 out of 83). Infection was limited only to the Sweama area on the Dead Sea (within the warm desert-climatic zone), with prevalence of 30.5%...
Instability-induced osteoarthritis in the metacarpophalangeal joint of horses. To establish an instability model of osteoarthritis (OA) that mimics the early changes of naturally acquired OA. Methods: 6 mature radiographically normal horses. Procedure-The collateral and lateral collateral sesamoidean ligaments were transected in a metacarpophalangeal (MCP) joint in each horse. Lameness examinations were performed every 7 days after surgery for 8 weeks. Radiographs were taken immediately before and after desmotomy and 8 weeks after surgery. Eight weeks after surgery, bilateral MCP joints were grossly evaluated, specimens of articular cartilage were harvested for histologi...
Musculoskeletal system neoplasia. Tumors of the musculoskeletal system are rare in horses; however, they must be taken seriously. Diagnosis requires observation of clinical signs, radiographic findings, and histological examination. Veterinarians must realize prognosis is not favorable for most tumors; however, some of these tumors can be treated or at least ameliorated. Tumors discussed in this article include: osteoma and osteosarcoma; osteoblastoma; chondrosarcoma; fibroma and fibrosarcoma; plasma cell myeloma; synovioma; rhabdomyosarcoma and tumors metastatic to the musculoskeletal system.
Tumors of the central nervous system. Neoplasia of the central nervous system (CNS) can be divided into two main categories: nonpituitary CNS neoplasia and pituitary adenomas. Nonpituitary CNS neoplasias are generally compressive in nature, although some are also invasive. The majority of reported CNS tumors are secondary with only a few originating from nervous tissue. Pituitary adenomas predominantly occur in the pars intermedia of the older horse. Clinical signs, diagnostic testing, and possible treatments are discussed.
Abdominal neoplasia (excluding urogenital tract). Neoplasia of the equine gastrointestinal tract and abdominal organs occurs predominantly in geriatric horses, although lymphoma and hepatocellular carcinoma and a few other neoplasms can be found in young horses. This article discusses diagnostics that can be used in weight-loss situations, suspicious of neoplasia, as well as tumors themselves including clinical signs, diagnostic tools, histopathologic appearance, and management.
Neoplasia of the respiratory tract. Tumors of the equine respiratory tract occur infrequently. An accurate diagnosis of neoplasia of the respiratory tract is critical because the prognosis is usually grave. The clinical signs and diagnostic procedures are discussed for tumors of the nasal and paranasal sinuses, nasopharynx/larynx, guttural pouch and thorax including lung, pleura, and thymus.
Urinary tract neoplasia. This article is a review of reports on neoplasia of the equine urinary tract. Clinical signs associated with equine patients with urinary tract neoplasia are summarized along with a description of diagnostic methods used in such patients. The prognosis for treatment of urinary tract neoplasia is guarded. A review of the limited treatments that have been reported to date are also provided in this article.
An equine herpesvirus 1 mutant with a lacZ insertion between open reading frames 62 and 63 is replication competent and causes disease in the murine respiratory model. An equine herpesvirus 1 (EHV-1) mutant was constructed by inserting a lacZ expression cassette into the intergenic region upstream of gene 62 (glycoprotein L; gL) and downstream of gene 63 (a homologue of the herpes simplex virus transcriptional activator ICP0). The recombinant lacZ62/63-EHV-1 had similar growth kinetics in cell culture to those of the parental wild type (wt) virus, with indistinguishable cytopathic effects and plaque morphology. Reverse transcriptase PCR confirmed that the lacZ insertion did not interfere with transcription of gL and immunoblot analysis indicated there was no...
Effect of moderate exercise on the severity of clinical signs associated with influenza virus infection in horses. The purpose of this experiment was to determine if exercising horses, infected with influenza virus, exacerbates the severity of clinical disease. Eight horses were trained on a treadmill for 42 days and then challenged with aerosolised influenza A/equine/Kentucky/91 (H3N8). Following challenge, 4 horses (exercise group) continued training for 28 days, while the other 4 horses (nonexercise group) were confined to their stalls. All horses developed clinical signs within 36 h of challenge (fever, coughing, and mucopurulent nasal discharge) and clinical scores were greater in the exercise group. ...
Normal variation in, and effect of 2% pilocarpine on, intraocular pressure and pupil size in female horses. To determine normal variation in, and effect of 2% pilocarpine hydrochloride on, intraocular pressure (IOP) and pupil size in female horses during a specified period. Methods: 10 female horses with normotensive eyes. Methods: IOP and horizontal and vertical pupil size were measured on a single day between 8 AM and 8 PM at hours 0, 0.5, 1, 2, 4, 6, 8, 10, and 12. Measurements were repeated after single- dose application of 2% pilocarpine to both eyes. IOP and pupil size were measured at 8 AM and noon in a 5-day experiment of twice-daily application of 2% pilocarpine. Results: Variation in IOP a...
Persistent right aortic arch in a yearling horse. A 14-month-old filly with chronic pharyngitis was diagnosed with incomplete esophageal constriction and megaesophagus due to a persistent right aortic arch. This report is unusual because clinical signs of respiratory dysfunction secondary to chronic regurgitation occurred prior to the recognition of dysphagia.
Osteochondritis dessicans and subchondral cystic lesions in draft horses: a retrospective study. The clinical features, radiographic findings, treatment, and outcome in 51 draft horses with osteochondritis dessicans (OCD) or subchondral cystic lesions (SC) are reported. Clydesdale and Percheron were the most commonly affected breeds, and affected animals represented only 5% of the hospital population of draft horses. Horses were most frequently affected in the tibiotarsal joints and 73% (24 of 33 cases) of the horses with tibiotarsal effusion were affected bilaterally. Osteochondritis dessicans of the distal intermediate ridge was the most common lesion found in the tibiotarsal joint. The...
Laparoscopic diagnosis of subcapsular splenic hematoma in a horse. A 5-year-old Quarter Horse was examined after it developed signs of abdominal discomfort as a result of a training accident. Oral mucous membranes were pale, and capillary refill time was > 3 seconds. Hematologically, the PCV was low, and abdominocentesis yielded a serosanguineous fluid. Abdominal ultrasonography was performed and revealed a large hypoechoic mass associated with the cranial margin of the spleen. Because differentiation between subcapsular hematoma and extracapsular hematoma could not be made with certainty, further evaluation of the spleen was indicated. Abdominal laparosco...
Occult osseous metastasis of a colonic adenocarcinoma visualized with technetium tc 99m hydroxymethylene diphosphate scintigraphy in a horse. A 5-year-old Arabian horse was admitted with a 5-day history of undulant pyrexia of unknown origin, inappetence, obtundation, and acute collapse. Physical examination results were unremarkable except for a grade II/VI left-sided systolic cardiac murmur and abdominal splinting. Mild chronic inflammatory changes were evident on clinicopathologic evaluation. Echocardiography revealed moderate aortic insufficiency. A solitary soft tissue opacity was found on thoracic radiography but not on ultrasonography. Palliative treatment was ineffective. Nuclear scintigraphy with WBC labeled with technetium ...
Clinical, serologic, and histopathologic characterization of experimental Borna disease in ponies. Borna disease was originally described as an equine neurologic syndrome over 200 years ago, although the infectious etiology of the disorder was unproven until the early 20th century. Borna disease virus (BDV) was finally isolated from horses dying of the disorder, and that virus has been used to experimentally reproduce Borna disease in several species of laboratory animals. However, BDV has never been inoculated back into horses to experimentally and etiologically confirm the classic clinical, pathologic, and serologic characteristics of the disease in that species. Three ponies were intrace...
Changes in plasma protein concentrations in ponies with experimentally induced alimentary laminitis. To determine whether plasma protein concentrations were altered in ponies with alimentary laminitis. Methods: 12 adult ponies. Methods: Acute laminitis was induced in 6 ponies by oral administration of carbohydrate (85% corn starch, 15% wood flour); the other 6 ponies were used as controls. A physical examination was performed and blood samples were collected immediately before and 4, 8, 12, 24, and 28 hours after administration of carbohydrate. Plasma protein concentrations were determined by means of sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Results: 19 plasma proteins rang...
Pathophysiology of acquired dental diseases of the horse. Periodontitis, infundibular necrosis, and periapical infection are dental diseases commonly affecting adult horses. Routine dental examinations and care may help to prevent these diseases. Further investigation of the treatment of horses with these diseases using local antimicrobial therapy, restorative dentistry, and endodontic therapy is needed. An understanding of the pathogenesis of these diseases aids in diagnosis and treatment. Gingival hyperplasia and odontogenic tumors are uncommon but should remain in a list of differential diagnoses when examining a horse with pertinent clinical sign...
Dental surgery in horses. Dental surgery is most often directed at removal of diseased or injured teeth by the least invasive method possible. Some procedures available can preserve traumatized or infected teeth. Complications of dental surgery are well documented and often encountered by veterinary surgeons. Principles of debridement, curettage, lavage and ventral drainage combined with appropriate medicinal management can reduce complications and lead to successful outcome after dental surgery.
Dental corrective procedures. This article explains what is needed for successful extraction of diseased cheek teeth and how to realign the occlusal surface. Incisor teeth procedures and correcting abnormalities of cheek tooth crown wear are also discussed along with wolf and floating teeth.
Experimental infection of the human granulocytic ehrlichiosis agent in horses. Human blood collected from two patients from Westchester County, New York with human granulocytic ehrlichia (HGE) infection was inoculated into two ponies. Inoculated ponies developed clinical signs similar to a previous report (Madigan et al., 1995). Histopathological changes involved follicular hyperplasia of lymphoid tissues. HGE DNA was detected by PCR in muscle, fascia, peritoneum, and adrenal gland after the ponies produced a high level of antibodies to HGE. We suggest that HGE may reside in poorly vascularized connective tissues, where the antibodies may have some difficulties to penetr...
Pulmonary function in horses with recurrent airway obstruction after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. To determine changes in clinical signs of disease and response to pulmonary function testing in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively. Methods: 6 horses with inducible and reversible heaves. Methods: Episodes of heaves were induced by exposure (challenge) to moldy hay and straw for 7 days. Horses were assigned to treatment groups (aerosolized beclomethasone dipropionate, parenterally administered dexamethasone, aerosolized propellant [control]), and respiratory frequency and s...
Serum gentamicin concentrations in compromised neonatal foals. Twenty-one compromised neonatal foals hospitalised at the Rural Veterinary Centre (RVC) during 1993 were studied to determine i) serum gentamicin concentrations obtained when gentamicin was administered at 3.3 mg/kg bwt twice daily i.m.; ii) factors which contributed to inter-foal variation in serum gentamicin concentrations achieved and iii) clinical efficacy of gentamicin therapy in foals with confirmed septicaemia. Septicaemia was confirmed in 7 foals with positive blood cultures and suspected in 8 foals with a sepsis score > 11. Peak serum concentrations (Ps) were > 6 microg/ml in al...
Monitoring and detection of acute viral respiratory tract disease in horses. To develop a system to monitor and detect acute infections of the upper respiratory tract (i.e., nares, nasopharynx, and pharynx) in horses and to assess the association among specific viral infections, risk factors, and clinical signs of disease. Methods: Prospective study. Methods: 151 horses with clinical signs of acute infectious upper respiratory tract disease (IURD) from 56 premises in Colorado. Methods: Health management data, blood samples, and nasal or nasopharyngeal swab samples were obtained for 151 horses with clinical signs of acute IURD. Of these horses, 112 had an additional blo...
Local and systemic isotype-specific antibody responses to equine influenza virus infection versus conventional vaccination. Inactivated alum-adjuvanted conventional equine influenza virus vaccines are of poor efficacy and offer limited short-term protection against infection. In sharp contrast, natural infection with equine influenza virus confers long-term protective immunity. In order to identify the protective immune responses to equine influenza virus, the influenza virus-specific IgA, IgGa, IgGb, IgGc and IgG(T) antibody responses in nasal secretions and serum induced by natural infection and a commercial vaccine were studied by ELISA. Two groups of four influenza-naive ponies were established. In the natural ...
