Peripheral lymphocyte function in dogs with Brucella canis infection

Peripheral lymphocyte function in dogs with Brucella canis infection was evaluated using in vitro lymphocyte stimulation with the mitogens PHA, Con A and PWM, and killed Brucella canis organisms. Bitches with naturally occurring Brucella canis infection were compared to negative controls. There was no difference in the response to Con A and PWM between these two groups. Lymphocytes from infected dogs were less responsive (p less than .05) to PHA than were lymphocytes from controls. There was a significant (p less than .005) difference in response to Brucella canis antigen between the two groups. Lymphocytes from infected dogs were stimulated by Brucella canis antigen, whereas those from controls did not respond.     

Vacuum phenomenon associated with osteochondrosis of the scapulohumeral joint in dogs: 100 cases (1985-1991).

The vacuum phenomenon was visualized in 20 of 100 scapulohumeral joints with osteochondritic lesions in 65 dogs. The phenomenon was associated with the finding of a cartilage flap, lack of joint effusion, and clinical signs of pain and lameness. The vacuum phenomenon was not observed on radiography of 30 clinically normal contralateral joints, and it could not be induced in 36 clinically normal scapulohumeral joints radiographed under stressed extension.     

Thoracotomy in adult dairy cattle: 14 cases (1979-1991).

Fourteen cows were subjected to thoracotomy as an aid in the treatment of either septic pericarditis (n = 7) or unilateral pleuritis (fibrous or purulent; n = 7). Thoracic lesions were primary in 4 cows, secondary to traumatic reticuloperitonitis in 9 cows, and secondary to extension of a liver abscess in 1 cow. Thoracotomy was performed on 9 cows under local anesthesia. Surgery was performed on 5 cows under general anesthesia; 2 died during anesthesia, and 2 others were euthanatized. Of the 10 cows allowed to recover from surgery, 4 had pericarditis and 6 had pleuritis. Four cows with pleuritis had thoracic abscesses. All but 1 cow with pericarditis died or were euthanatized, and 5 of the 6 cows with pleuritis were discharged from the hospital. A year after surgery, 1 cow was culled because of infertility, and the other 5 cows were returned to production.     

Prevalence of Dirofilaria immitis and Dipetalonema reconditum infection in dogs: 805 cases (1980-1989).

Clinical records of 6,977 dogs examined at the small animal clinic of the University of Tennessee College of Veterinary Medicine from January 1980 through December 1989 were analyzed to determine the prevalence and changing frequency of Dirofilaria immitis and Dipetalonema reconditum infection. Using the Knott's test on these dogs, 805 (11.54%) tested positive for microfilariae, with D immitis in 430 dogs (6.16%), and Dip reconditum in 375 dogs (5.37%). Statistical analysis confirmed that the prevalence of D immitis and that of Dip reconditum were essentially equal in the population of dogs included in this study. There was a slight decrease in the prevalence of D immitis over the 10 years examined, but the prevalence of Dip reconditum remained constant. The results were not affected by year-to-year variability in the number of examinations performed. On the basis of our findings, in eastern Tennessee, those veterinarians who diagnose heartworm infection by the presence of microfilariae without differentiating the species involved, risk misdiagnosing 50% of the cases. If the patterns of prevalence seen in recent years continue, the chances of error may actually increase.     

Enteric Clostridium perfringens infection associated with parvoviral enteritis in dogs: 74 cases (1987-1990).

Parvovirus infection was confirmed by fluorescent antibody staining of or viral isolation from specimens of small intestine in 181 (17%) of 1,110 dogs necropsied between July 1, 1987 and Dec 31, 1990. Clostridium perfringens was isolated from 74 (69%) of 108 dogs with parvovirus infection from which specimens of jejunum also had been obtained for culture of anaerobic bacteria. Gram-positive bacilli in association with focal to diffuse necrosis of the superficial portions of the villi were observed in histologic sections of specimens of small intestine from 56 (98%) of 57 dogs from which parvovirus and C perfringens had been identified. These findings indicate that C perfringens frequently proliferates in dogs with parvovirus infection.     

Cutaneous actinomycosis and nocardiosis in dogs: 48 cases (1980-1990).

Medical records of 48 dogs with cutaneous actinomycosis or nocardiosis were reviewed. Male, large-breed dogs kept outdoors were overrepresented. The mean age at admission was 3.6 years. Cutaneous swelling (68%), abscesses (65%), draining tracts (48%), fever (36%), and signs of pain (13%) were the most common clinical findings. The cervicofacial area was affected in 48% of the dogs. Abdominal and thoracic wall involvement was less common. Leukocytosis, neutrophilia with left shift, monocytosis, and hyperglobulinemia were common. The diagnosis was confirmed by cytologic examination, bacteriologic culture, or histologic examination. Gram-positive filamentous bacteria were seen in 69% of the fine needle aspirates and in 50% of the biopsy specimens. Actinomyces spp were isolated from cutaneous lesions in 27 (60%) dogs. Nocardia asteroides was isolated from 1 dog. Treatment consisted of surgical debridement, drainage, and administration of antibiotics in 29 dogs (group A) and antibiotics alone in 13 dogs (group B). The infection redeveloped in 10 (42%) group-A dogs and 6 (60%) group-B dogs. Of the 10 group-A dogs with recurrent infection, 6 had resolution after a second surgery and 4 were euthanatized. Of the 6 group-B dogs, 1 had resolution after surgery, 4 were euthanatized or died because of persistent disease, and 1 had an unresolved infection. The combination of surgery and antibiotic treatment appeared to be superior to antibiotic treatment alone in resolving cutaneous Actinomyces and Nocardia infections.     

Ocular lesions associated with coccidioidomycosis in dogs: 35 cases (1980-1985)

Thirty-five dogs with ocular lesions associated with coccidioidomycosis were examined. Serologic and/or histologic evaluation confirmed the diagnoses of coccidioidomycosis. The disease most frequently associated with signs referable to the anterior segment of the eye, such as iritis and granulomatous uveitis. Histologic evaluation of the eye revealed a primary posterior segment disease, such as chorioretinitis or retinal separation, with an extension into the anterior segment of the eye.     

Brucella abortus infection in 14 farm dogs

Fourteen dogs were obtained from 10 farms with Brucella-infected cattle and were studied for periods ranging from 2 to 81 days. At necropsy, Brucella abortus biovar 4 was isolated from all 14 dogs. Mandibular, medial retropharyngeal, tracheobronchial, and mesenteric lymph nodes yielded the highest rate of recovery. Urogenital infection with active shedding was seen in a single aged bitch. Fecal samples (291 from 13 dogs) were B abortus culture negative. Ten dogs monitored serologically over time had standard tube agglutination test titers that fluctuated between 1:50 with incomplete reaction and greater than or equal to 1:200 with positive reaction. At necropsy, the magnitude of seroconversion was not directly related to the number of culture-positive tissues. The maximal duration of infection, based on the time interval between the last possible exposure to infected cattle and recovery of the organism at necropsy, was 464 days. If it were assumed that infection occurred at about the same time as seroconversion in the cattle herd of origin, maximal observed duration of infection was 539 days. The actual maximal duration of infection could not be determined from this study, but would have exceeded the values reported here. The data indicate that dogs have the potential to infect cattle and could pose a threat for longer duration of disease transmission than had previously been assumed. Although the risk of transmission appears small, infection of human beings or cattle associated with Brucella-infected dogs would cause unfavorable political and economic consequences, particularly in low-incidence areas. Removal of contact dogs from infected herds should prevent such transmission.     

Enteral feeding of dogs and cats: 51 cases (1989-1991).

Feeding commercial enteral diets to critically ill dogs and cats via nasogastric tubes was an appropriate means for providing nutritional support and was associated with few complications. Twenty-six cats and 25 dogs in the intensive care unit of our teaching hospital were evaluated for malnutrition and identified as candidates for nutritional support via nasogastric tube. Four commercial liquid formula diets and one protein supplement designed for use in human beings were fed to the dogs and cats. Outcome variables used to assess efficacy and safety of nutritional support were return to voluntary food intake, maintenance of body weight to within 10% of admission weight, and complications associated with feeding liquid diets. Sixty-three percent of animals experienced no complications with enteral feedings; resumption of food intake began for most animals (52%) while they were still in the hospital. Weight was maintained in 61% of the animals (16 of 26 cats and 15 of 25 dogs). Complications that did occur included vomiting, diarrhea, and inadvertent tube removal. Most problems were resolved by changing the diet or adhering to the recommended feeding protocol. Nutritional support as a component of therapy in small animals often is initiated late in the course of the disease when animals have not recovered as quickly as expected. If begun before the animal becomes nutrient depleted, enteral feeding may better support the animal and avoid serious complications.     

Polymyositis associated with Ehrlichia canis infection in two dogs

Clinical, haematological, biochemical, electrophysiological and pathological features of two dogs infected with Ehrlichia canis and with concurrent signs of polymyositis are presented. Both dogs had a history of relatively acute onset, progressive tetraparesis, hyporeflexia and generalised muscle wasting. Skeletal muscles were atrophic and characterised histologically by plasmocytic, lymphocytic and immature lymph-oreticular cellular infiltrates with accompanying areas of necrosis. Histopathological similarities between ehrlichiosis and polymyositis are noted and a probable aetiological relationship is inferred.     

Idiopathic muscular hypertrophy of the equine small intestine: 11 cases (1980-1991).

The medical records of 11 horses with idiopathic muscular hypertrophy (MH) of the small intestine were reviewed to determine the clinical and pathological features of the disease. The median age of affected horses was 10.0 years (range 5-18 years). No breed or sex predisposition was apparent. Ten horses (91%) had chronic (23 days to 2.4 years) signs of mild, intermittent colic, and 1 horse had signs of severe colic of only 3 days' duration. Partial anorexia and chronic weight loss of variable duration (1-6 months) were prominent historical findings in 5 (45%) horses. Diagnostic tests, with the exception of exploratory caeliotomy, were ineffective for definitive diagnosis of intestinal MH as a cause of colic. In 2 horses, however, a thickened, rigid ileum was detected by palpation per rectum, and in 5 horses, multiple loops of distended small intestine were detected by palpation per rectum. Hypertrophy of both the circular and longitudinal layers of muscularis was determined as the cause of intestinal thickening in all horses. Muscular hypertrophy of the ileum was present in 9 (82%) horses. Two horses (18%) had MH of a section of jejunum only, and 4 (36%) horses had MH of the ileum in combination with MH of other sections of small intestine. Two (18%) horses had MH of the entire small intestine. In 9 (82%) horses, intestinal MH resulted in narrowing of the luminal diameter at the site of MH. Small diverticula were present on the mesenteric border of the hypertrophied ileum of 5 (45%) horses. Five linear (up to 150-cm) diverticula were present in the hypertrophied jejunum of 1 (9%) horse. Haemomelasma ilei was present on the antimesenteric serosal surface of affected intestine of 8 (73%) horses. Full-thickness rupture of the ileum with subsequent diffuse, septic peritonitis occurred in 3 (27%) horses.     

Respiratory and cardiopulmonary arrest in dogs and cats: 265 cases (1986-1991).

Outcomes of cardiopulmonary arrest and resuscitation in clinically affected dogs and cats have not been adequately studied. We examined the records from 200 dogs and 65 cats that had received cardiopulmonary resuscitation for respiratory or cardiopulmonary arrest; none of the animals had been anesthetized or intubated at the time of arrest, and all had been hospitalized in a veterinary critical care facility. Cardiopulmonary arrest was found to be more common than respiratory arrest in dogs and cats. Hospital discharge rates for animals with cardiopulmonary arrest ranged from 4.1% for dogs to 9.6% for cats, and were consistent with those reported from studies of human beings with cardiopulmonary arrest. Hospital discharge rates for dogs and cats with respiratory arrest were 28% and 58.3%, respectively.     

Clinical signs associated with brain tumors in dogs: 97 cases (1992-1997).

OBJECTIVE: To determine the prevalence of various clinical signs in dogs with brain tumors. DESIGN: Retrospective study. ANIMALS: 97 dogs with brain tumors. PROCEDURE: Medical records were reviewed for signalment, tumor type and location, and clinical signs. RESULTS: 33 breeds were represented; Golden Retrievers were most commonly affected. Most dogs were older (median age, 9 years); 95% of dogs were > or = 5 years old. Seventy-six percent of dogs had tumors in the supratentorial region. Seizures were the most common clinical sign at initial examination, with lower prevalence for circling, ataxia, and head tilt. Meningioma was the most common tumor. CONCLUSIONS AND CLINICAL RELEVANCE: Brain tumors develop most often in dogs > or = 5 years old and are uncommon in dogs < 5 years old. Seizures are a common clinical sign, and a brain tumor should be considered in dogs that have their first seizure after they are 4 years old.     

Gram-negative bacterial infection in neonatal New World camelids: six cases (1985-1991).

Gram-negative bacterial infections were documented in 6 neonatal New World camelids (5 Ilamas and 1 alpaca). The organisms isolated from blood before death or from multiple organs after death were Escherichia coli (n = 3), Actinobacillus sp (n = 1), and Klebsiella pneumoniae (n = 1). Only 2 crias survived, and 1 became blind secondary to retinal detachment and ocular inflammation, which developed after treatment for bacterial infection. Abnormal events during the perinatal period (prematurity, dystocia, cesarean section, weak at birth) were reported in all 6 crias. Signs of depression, convulsions, and/or coma were observed in all animals. Diarrhea and respiratory distress were also noticed in the 3 crias that died shortly after admission. Serum immunoglobulins were assessed, but without the benefit of a stall-side test specific for Ilama immunoglobulins. All crias were suspected to have poor transfer of maternal immunoglobulins. Hemograms and serum biochemical values prior to the initiation of treatment were obtained on 5 of the 6 crias. Total nucleated cells ranged from 1,400 to 23,100 cells/microliter. Four of the 5 crias has a left shift, and 2 crias had toxic neutrophils. Serum glucose concentrations, measured in 5 of 6 crias, ranged from 83 to 293 mg/dl. Serum creatinine values were high in 2 of 5 crias, 1 of which had acute tubular necrosis. Three crias with high serum electrolyte (sodium, chloride, or potassium) values subsequently died. Arterial blood gas values were assessed in 3 crias, 1 of which had respiratory alkalosis and mild hypoxemia.     

Treatment of chronic pleural effusion with pleuroperitoneal shunts in dogs: 14 cases (1985-1999).

OBJECTIVE: To describe complications and outcome associated with chronic nonseptic pleural effusion treated with pleuroperitoneal shunts in dogs. DESIGN: Retrospective study. ANIMALS: 14 dogs. PROCEDURE: Medical records at 4 veterinary schools were examined to identify dogs with chronic nonseptic pleural effusion that were treated by use of a pleuroperitoneal shunt between 1985 and 1999. Signalment, history, physical examination and laboratory findings, cause and type of pleural effusion, medical and surgical treatments, complications, and outcome were reviewed. RESULTS: 10 of 14 dogs had idiopathic chylothorax, and 4 had an identified disease. All but 1 dog with idiopathic chylothorax and 1 dog with chylothorax from a heart base tumor had unsuccessful thoracic duct ligation prior to pump placement. No intraoperative complications developed during shunt placement. Short-term complications developed in 7 of 13 dogs, necessitating shunt removal in 2 dogs and euthanasia in 1. Eight of 11 dogs with long-term follow-up developed complications; the overall mean survival time and the interval in which dogs remained free of clinical signs of pleural effusion were 27 months (range, 1 to 108 months) and 20 months (range, 0.5 to 108 months), respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Pleuroperitoneal shunts can effectively palliate clinical signs associated with intractable pleural effusion in dogs. Numerous short- and long-term complications related to the shunt should be expected. Most complications can be successfully managed, but even when shunts are functional some treatments fail because of severe abdominal distension or massive pleural fluid production that overwhelms the functional capacity of the shunt.