Gastric emptying of nondigestible radiopaque markers after circumcostal gastropexy in clinically normal dogs and dogs with gastric dilatation-volvulus.

Using radiopaque particles mixed with food, gastric emptying was assessed in healthy dogs not subjected to surgery, in healthy dogs 9 to 35 days after circumcostal gastropexy, and, in dogs 1 to 54 months after surgical treatment and recovery from gastric dilatation-volvulus (GDV). Circumcostal gastropexy surgery did not alter the 90% gastric emptying time for radiopaque particles in healthy dogs. However, 90% gastric emptying time was significantly (P less than 0.05) increased after circumcostal gastropexy in dogs with GDV, compared with healthy dogs after the same surgical procedure and recovery period. These results imply that dogs with GDV have delayed gastric emptying of solid particles. Whether delayed gastric emptying of markers detected in affected dogs after surgical treatment and recovery was the result or the cause of GDV was not determined. Results indicate that circumcostal gastropexy could be recommended as a prophylactic procedure for GDV in large breeds with deep thorax, because delayed gastric emptying of markers secondary to the surgical procedure is unlikely.

Pulmonary particle deposition and airway mucociliary clearance in cold-exposed calves.

Effect of cold-induced changes in respiratory pattern on pulmonary particle deposition was investigated in 10 male Holstein calves between the ages of 1 and 3 months. Deposition of intranasally instilled fluorescence-enhanced Pasteurella haemolytica was significantly higher (P less than 0.05) for cold-exposed calves and appears to be caused by the cold-induced respiratory pattern change. Deposition was greater in apical and mediastinal lung lobes, but the reason for this preferential deposition is uncertain. Nasal mucus velocity was measured in 4 nonanesthetized calves at ambient temperature of 2 to 4 C and 16 to 18 C, using tantalum-paraffin oil droplets and serial radiography. Nasal mucus velocity was 24% lower during cold exposure. In addition, the effect of mucosal temperature on tracheal mucus velocity was determined in excised tracheas from 7 calves. A direct relationship existed between mucosal temperature and tracheal mucus velocity within the mucosal temperature range studied (35.0 to 39.5 C). Tracheal air temperature measurements in calves at ambient temperatures of -10.4 C (n = 4) and 18.5 C (n = 5) indicated that conditioning of inspired air is not complete at the tracheal level during extreme cold exposure. Therefore, cold air may directly influence tracheal mucociliary clearance. It is speculated that cold exposure increases pulmonary deposition of pathogens, while simultaneously decreasing mucociliary clearance of the upper airways, thus predisposing cold-exposed calves to respiratory tract infection.

Ultrasonographic features of splenic lymphosarcoma in dogs: 12 cases (1980-1986).

The ultrasonographic appearance of the spleen and adjacent organs in 12 dogs with splenic lymphosarcoma was reviewed. Poorly marginated hypoechoic to anechoic nodules (4 mm to 3 cm in diameter) were found in all dogs. The anechoic nodules did not result in reflective shadowing or acoustic enhancement of the underlying tissues. The remainder of the splenic parenchyma appeared relatively hypoechoic when compared with the liver or renal cortices in 9 dogs. Recognition of this ultrasonographic pattern appears to be a useful diagnostic tool. Needle aspiration guided ultrasonographically will then enable histologic confirmation of lymphosarcoma.

Ultrasonographic features of splenic hemangiosarcoma in dogs: 18 cases (1980-1986).

The medical records of 18 dogs in which ultrasonography was useful in making a diagnosis of splenic hemangiosarcoma were reviewed. Splenic ultrasonography revealed masses with echo patterns that ranged from anechoic fluid to hyperechoic tissue. In 7 dogs, metastasis was detected ultrasonographically as anechoic to hypoechoic lesions in the liver.

Ultrasonographic diagnosis of portacaval shunts in young dogs.

Ultrasonography was performed on 21 young dogs with portacaval shunts. Initial ultrasonography revealed a small hypovascular liver in all dogs. Eight portacaval shunts (4 intrahepatic, 4 extrahepatic) were detected. Supplementary ultrasonography of dogs under general anesthesia and subjected to positive-pressure ventilation identified 6 additional intrahepatic portacaval shunts.

Comparison of various treatments for experimentally induced equine infectious arthritis.

To evaluate the effects of 5 treatments on clinical responses, synovial fluid analysis, radiographic changes, bacteriologic culture results of the synovial fluid and synovial membrane, microscopic characteristics of the synovial membrane, and articular cartilage histochemistry, Staphylococcus aureus organisms (1.6 X 10(6) colony-forming units) were inoculated into the tarsocrural joints of 12 horses (n = 24 joints; 2 joints/horse). Each horse was given phenylbutazone (2 g) orally, every 24 hours, beginning 24 hours after inoculation. Two horses (ie, 4 joints) were not given other treatment (controls; group 1). All other horses (ie, 20 joints) were given a trimethoprim-sulfadiazine combination orally, once daily (30 mg/kg; 8 joints) or twice daily (30 mg/kg q 12 hr; 12 joints). Each of these 20 joints were assigned to 1 of 5 treatment groups (4 joints/group) in a balanced incomplete block design. Group 2 (4 joints) was given only the antibiotics once daily. Twelve joints were treated by through-and-through joint lavage on day 1 (group 3), days 1 and 3 (group 4), or days 1, 3, and 6 (group 5). Joints in group 6 had an arthrotomy performed on day 1, with subsequent lavage via an indwelling drain every 12 hours for 4 days. In groups 3 through 6, 1 joint in each group was treated with antibiotics once daily, and 3 joints were treated with antibiotics twice daily. All horses were clinically assessed each day. Complete blood count was performed on days 3, 6, 10, and 21. Before inoculation and on days 0, 1, 3, 6, 10, and 21, synovial fluid specimens were collected and analyzed for color, clarity, total protein concentration, WBC count, differential count, and mucin clot-forming ability. Synovial fluid specimens were cultured bacteriologically before inoculation and on days 0 and 21. Horses in group 1 (controls) were euthanatized before day 6. All other horses were euthanatized on day 21. Tarsocrural joints were opened and examined. Synovial membrane specimens were bacteriologically cultured. Synovial membrane specimens were examined histologically (hemotoxylin and eosin stain) and articular cartilage specimens were (safranin O fast green stain) evaluated histochemically. Synovial membrane specimens were histologically graded into 5 categories. Intensity of articular cartilage intercellular staining with safranin 0 was graded for superficial, outer intermediate, inner intermediate, and deep zones. Two-way analysis of variance was performed to evaluate differences among groups and across time for the determinants evaluated.(ABSTRACT TRUNCATED AT 400 WORDS)

Comparison of radiography and ultrasonography in the evaluation of renal lesions in the dog.

Survey abdominal radiographs, excretory urograms, and nephrosonograms were obtained from 14 dogs with renal lesions. Renal enlargement was suspected on survey radiographs and confirmed by excretory urography in 13 dogs. Radiographic differentiation between a solid and cystic renal lesion was not possible in 9 dogs. Ultrasonography determined the presence of solid masses in 12 dogs, established the presence of a renal cyst in the opposite kidney in 1 dog, and revealed hydronephrosis in 2 dogs. Ultrasonography appeared to be more sensitive than radiography in differentiating the internal characteristics of renal lesions.

Plutonium-induced wounds in beagles.

Beagle dogs were given subcutaneous implants of plutonium in their forepaws to mimic hand wounds received by workers accidentally contaminated with plutonium. Ten dogs received 9.46 +/- 0.43 mu Ci of plutonium oxide, and eight dogs received 1.25 +/- 0.60 mu Ci of plutonium nitrate. Surviving dogs were sacrificed at 8 and 5 yr, respectively, after exposure, and radionanalyses were performed on the injection site, regional lymph nodes, liver, spleen and bone. Histopathologic and autoradiographic examinations were performed on injection sites, regional lymph nodes, livers, spleens, kidneys and grossly observed lesions. The injected paws sequestered 21 and 16%, respectively, of the injected activity from plutonium oxide and plutonium nitrate in hypocellular scar tissue. The highest concentrations of translocated radionuclides were found in the regional lymph nodes. Histopathologic and autoradiographic examinations of regional lymph nodes showed that the alpha activity was largely sequestered by scar tissue that replaced lymphoid parenchyma in the plutonium-oxide-injected dogs. In the plutonium-nitrate-injected dogs, activity was widely distributed in relatively intact regional lymph nodes. The liver had the next highest concentration for both radionuclides; activity was present as alpha stars. The spleen had the next highest concentration for plutonium-oxide-injected dogs, although concentrations in the spleen were lower than the skeleton in the plutonium-nitrate-injected dogs. Osteosarcomas and hepatomas were present in one dog injected with plutonium oxide. There does not appear to be any unique risk for dogs related to the subcutaneous route of exposure to plutonium.

Tuberculosis in greater kudu.

Four greater kudu (Tragelaphus strepsiceros) died while maintained in captivity at a zoo. Necropsy revealed tuberculous lesions in the lungs, spleen, and thoracic lymph nodes. Histopathologic findings included granulomas with Langhans' giant cells, necrosis, and mineralization. Acid-fast organisms isolated from tissues of each kudu were identified as Mycobacterium bovis.