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.
The acute abdominal patient: postoperative management and complications. The postoperative management of the surgical colic patient varies according to the complications experienced. Many of these complications can be related to the time at which surgery is performed
relative to commencement of the problem, the condition of the patient at the time of surgery, the particular condition, and, last but not
least, the surgeon's performance. Some of the points have been discussed elsewhere in the symposium. The maintenance of asepsis, attention to minimizing trauma to the bowel, and appropriate attention
to visceral and parietal closures are all important principles. ...
Brain abscess in three horses. Three horses with brain abscesses had different clinical manifestations: 1 had a protracted clinical course whereas 2 had a short clinical course. Clinical signs in 2 horses (1 acute case, 1 chronic case) included unilateral loss of vision, head tilt, circling, abnormal mental status, and ataxia. The 3rd horse had bilateral loss of vision, altered mental status, and apparent deafness. Results of cerebrospinal fluid analysis were inconsistent. The horse with the protracted clinical course had paradoxic central vestibular disease.
Acute vitamin D2 (ergocalciferol) toxicosis in horses: case report and experimental studies. Acute accidental vitamin D2 (ergocalciferol) toxicosis was diagnosed in a 6-month-old foal with extensive lesions of soft tissue mineralization. In an experimental study, three 18-month-old horses were given ergocalciferol per os at a rate of 9,300, 22,200, or 47,200 IU/kg of body weight/day for 21 days. Clinical signs or lesions were not seen in horses given the low and intermediate doses, whereas the horse receiving the highest dose developed clinical signs and lesions similar to those noted in the foal. Signs included depression, loss of appetite, weakness, limb stiffness with impaired mobi...
Effect of intra-articular injection of orgotein and saline solution on equine synovia. Orgotein was injected into the right intercarpal joint of each of 8 horses; the corresponding left joint was left alone (not injected) or was given an injection of normal saline solution. Injection with orgotein caused a transient, marked inflammatory response, evidenced by clinical signs and by increased leukocytes and total protein in the synovia (synovial fluid). Leukocyte numbers and total protein concentration were increased (P less than 0.010) in the orgotein-injected joints within 24 hours. However, saline solution alone also elicited a marked inflammatory response, manifested by increa...
Controlled tests of fenbendazole against migrating Strongylus vulgaris in ponies. Sixteen pony foals were reared worm-free and inoculated with Strongylus vulgaris. On day 7 after inoculation, 12 ponies were given a fenbendazole 10% suspension at dose rate of 50 mg/kg of body weight by stomach tube. On day 8 after inoculation, 8 of these ponies were given the 2nd treatment of the anthelmintic and on day 9, 4 of these ponies were given the 3rd treatment. (The other 4 of the 16 ponies were given only tap water, as controls.) The ponies were necropsied at death or on day 28 after inoculation. Fenbendazole was effective in minimizing the appearance of clinical signs associated w...
A mild form of strangles caused by an atypical Streptococcus equi. A mild form of strangles caused by an atypical Streptococcus equi was recognized on a large horse breeding farm. The organism differed from most S equi isolates by disappearance of the mucoid capsule by 24 hours of culture, leaving a matt-type colony. Typically, the clinical signs were a transient (24-48 hour) fever, profuse nasal discharge, and anorexia. In about half the affected animals, there was moderate mandibular lymph node enlargement, and these glands usually ruptured or were drained. The use of a passive hemagglutination antibody test showed that subclinical infection was widespread ...
Acquired inguinal hernia in the horse: a review of 27 cases. Twenty-seven cases of acquired inguinal hernia in the horse were reviewed. The history, clinical signs, treatment, and complications were summarized. Mortality was 25.9%. Only 13 or the 27 cases were diagnosed prior to admission. With early diagnosis and treatment, mortality should approach zero. In 24 of these cases, the hernia was strangulated. In each case, the signs were colic, a firm slightly enlarged testicle in the scrotum, and small intestine displacement through the inguinal ring, as determined via rectal palpation. In was concluded that palpation of the scrotum and inguinal rings sho...
Equine laryngeal hemiplegia. Part III. Treatment by laryngoplasty. During the years 1971-1979, 127 horses with left laryngeal hemiplegia were studied. The physical characteristics and clinical signs observed in this study were recorded in Part I and Part II of ths series of papers. Of these 127 horses, 81 were treated by the laryngoplasty procedure. Complications of surgery are described and the effects of the operation on respiratory noise and performance are evaluated. In 54.8% of horses the chronic respiratory noise observed during exercise was apparently diminished or eliminated post-operatively. The performance of 44% of horses was apparently improved af...
Equine laryngeal hemiplegia part II: Some clinical observations. Some clinical features of laryngeal hemiplegia in 127 horses are described. Possible aetiologic factors were found in only 11% of affected animals. The onset of clinical signs was either sudden or insidious. The majority of cases were presented because of an abnormal respiratory noise made at exercise. Other clinical signs, particularly those usually attributed to laryngopalatal dislocation, were observed in a substantial proportion of affected animals. In all cases surveyed the left arytenoid was affected, although in 3 animals a bilateral laryngeal dysfunction was noted. Thirty of 65 animals...
Chronic respiratory disease in a horse infected with Dictyocaulus arnfieldi. A 6-year-old Thoroughbred gelding was examined because of respiratory disease that developed after it was placed on pasture occupied by a donkey. Clinical signs in the gelding included a harsh, dry paroxysmal cough and increased expiratory effort. Eosinophils were seen in smears of mucus aspirated from the trachea and the bronchi. Immature, 5th-stage Dictyocaulus arnfieldi was identified in the tracheal mucus. The cough and other clinical signs were not diminished by corticosteroid therapy or by the administration of bronchodilators. Treatment with 10-fold therapeutic dosages of thiabendazole ...
Studies of an outbreak of Corynebacterium equi pneumonia in foals. Five out of 6 foals between 2 and 4 months old, on a ranch in northern California, developed pneumonia within a 3 week period in June and July 1978. Corynebacterium equi was recovered from each of the 5 foals by transtracheal aspiration. Clinical signs were variable but included increased respiratory rate, fever, cough, nasal discharge, harsh airway sounds over middle sized airways and wheezing over small airways. Cyanosis was present in the most severely affected foal. Radiographic findings included diffusely increased interstitial and peribronchial densities, areas of consolidation and, in 3...
Prophylactic effects of sodium cromoglycate on chronic obstructive pulmonary disease in the horse. When stabled in a controlled environment, horses effected with chronic obstructive pulmonary disease (COPD) became clinically asymptomatic in 4 to 32 days (mean [+/-sd] 9.1 +/- 4.9 days), the time being influenced most by the severity of the disease judged on maximum intrathoracic pressure change (Max delta Ppl) and the age of the animal. Sodium cromoglycate, a drug widely used for prophylaxis of allergic respiratory disease in man, was administered by inhalation to 56 COPD-affected horses. The results showed that a linear response existed between the number of successive days treatment with t...
Phenylbutazone toxicosis in equidae: a biochemical and pathophysiological study. Toxic effects of phenylbutazone (PBZ) in ponies and horses were studied, using a variety of biochemical, pathophysiologic, and pathologic methods. At dosage levels of 10 to 12 mg/kg of body weight/day for 8 to 10 days, ponies frequently developed clinical signs of toxicosis characterized by hypoproteinemia. Studies using 51CrCl3 demonstrated that PBZ caused a protein-losing gastroenteropathy. The plasma loss was usually associated with gastrointestinal ulceration, but sometimes occurred without obvious lesions in mildly affected animals. Similar studies (8.2 mg/kg/day for 13 days) in Thoroughb...
Clinical toxicosis and erythrocyte cholinesterase inhibition of trichlorfon combined with mebendazole in horses. Thirty adult horses were used to compare the toxicity and cholinesterase (ChE) inhibition of various dosages of a combination anthelmintic, trichlorfon + mebendazole. Single oral doses of up to 5 times the effective dosage (39.7 mg of trichlorfon and 8.8 mg of mebendazole/kg of body weight) did not result in deaths. Horses given a placebo and horses treated at the recommended dosage rate showed few or no side effects, whereas horses given higher dosages showed dosage-related increases in the severity of clinical signs of organophosphate toxicosis. Dosage-related inhibition of erythrocyte ChE a...
Pathologic features of horses given avirulent equine arteritis virus intramuscularly. Twenty horses that were seronegative for equine arteritis virus antibodies were inoculated IM with live equine arteritis virus vaccine. The inoculation did not cause clinical signs of disease. A mild, transient febrile reaction developed in 6 horses, 3 of which were in poor condition before inoculation. Six horses, 2 of which were in poor condition before inoculation, experienced mild lymphopenia. Necropsy revealed mild lesions in the lymph nodes of 6 horses (3 of which were in poor condition before inoculation). Maximum concentrations of virus were detected in the lymph nodes and were consist...
A comparative study of the toxicity of Fusarium verticillioides (= F. moniliforme) to horses, primates, pigs, sheep and rats. An isolate of Fusarium verticillioides (MRC826) that induced experimental leukoencephalomalacia, also caused acute toxicity when fed to pigs and administered per rumen fistula to sheep. Pigs developed severe pulmonary oedema while sheep manifested severe nephrosis and hepatosis. A less toxic isolate (F. verticillioides MRC602), fed to baboons, resulted in acute congestive heart failure or hepatic cirrhosis, depending on the dose. Both isolates were toxic to rats and caused similar lesions, namely, hepatic cirrhosis and intraventricular cardiac thrombosis.
Equine colitis “X”, still an enigma? Colitis "X" is a sporadic diarrheal disease of horses with clinical signs of dehydration, electrolyte imbalances and "shock"-like features. Macroscopic and microscopic findings include signs of disseminated intravascular coagulation, necrosis of colonic mucosa and presence of large numbers of bacteria in the devitalized parts of the intestine. Recently published work suggests that the causative agent may be Clostridium perfringens, Type A, but the bacteria are recoverable only in the preliminary stages of the disease. Excess protein and lack of cellulose content in the diet is thought to be th...
Equine protozoal myeloencephalitis: a report of two cases from Western Canada. Two cases of nonsuppurative myeloencephalitis are reported which clinically and pathologically resemble equine protozoal myeloencephalitis. Lesions in both horses were associated with Toxoplasma-like organisms visible in microscopic sections. Clinical signs and lesions in one case primarily involved the brain and in the other case principally involved the spinal cord and associated meninges. Positive identification of the organisms was not achieved; however, the etiological agent is unlikely to be a species of Toxoplasma. Recently published studies suggest a species of Sarcocystis is involved....
Osteochondrosis of the shoulder joint of the horse. Osteochondrosis of the shoulder joint in the horse was diagnosed radiographically in 54 shoulders of 38 horses. Clinical signs were those of an intermittent lameness characterized as a swinging leg shoulder lameness with pain elicited by extension, flexion or abduction of the limb. Diagnosis of shoulder lameness was supported by blocking the shoulder joint with local anesthetics. Radiographic changes consisted of: (1) alteration in the contour of the humeral head and glenoid cavity, (2) periarticular osteophyte formation, (3) sclerosis of the subchondral bone, and (4) bone cyst formation. The ...
Field outbreaks of leukoencephalomalacia in horses consuming maize infected by Fusarium verticillioides (= F. moniliforme) in South Africa. Four outbreaks of leukoencephalomalacia in horses in widely separated areas in South Africa are reported. The clinical signs and pathological lesions observed in each outbreak are briefly described. Mouldy home-grown maize from which Fusarium verticillioides (Sacc.) Nirenberg (= F. moniliforme Sheldon) was isolated in every instance, was involved in the outbreaks. Clinical signs and pathological lesions were identical to those seen in experimentally produced cases of F. verticillioides poisoning in horses.