Poxvirus and multiple tumors in an eastern gray squirrel

A moribund juvenile gray squirrel (Sciurus carolinensis) with numerous skin fibromas was submitted to the Northeastern Research Center for Wildlife Diseases. Necropsy revealed multiple firm white nodules in the lungs. On histologic examination, in addition to the skin lesions, fibromatous proliferations were seen in the wall of the alimentary tract, in 1 mesenteric lymph node, and in the myocardium. Tubular adenomas were seen in the renal cortex, and the lung nodules were bronchoalveolar adenomas. Eosinophilic intracytoplasmic poxvirus inclusion bodies were seen in both the mesenchymal and epithelial tumors.     

Physiologic and acid-base measures of gopher snakes during ketamine or halothane-nitrous oxide anesthesia

Arterial acid-base and selected physiologic measures of gopher snakes (Pituophis melanoleucus catenifer) during ketamine or halothane-nitrous oxide anesthesia were compared with base-line values. During ketamine anesthesia, significant decreases in pH and HCO-3 concentrations indicated acid-base states of uncompensated metabolic acidosis. In contrast, halothane-nitrous oxide anesthesia induced acidosis of respiratory origin, through a significant depression in respiratory rate. In addition to the conventional measures, the OH-/H+ ratios and the alpha-imidazole (alpha IM) values were calculated to assess acid-base status during anesthesia. Values for both factors decreased significantly during both ketamine and halothane-nitrous oxide anesthesia. Where H+ concentrations nearly doubled, the decline in the OH-/H+ ratio exceeded 70% and the alpha IM decreased less than 20%. It was concluded that these 2 factors may be helpful in evaluation of the acid-base status of ectothermic animals when normal values for the conventional measures of pH and pCO2 are not available for comparison.     

Depressed immunoconglutinin responses in calves experimentally infected with Trypanosoma congolense

Contrary to expectation, immunoconglutinin levels failed to rise significantly in calves infected with Trypanosoma congolense. In addition, it was shown that trypanosome infection appeared to inhibit the immunoconglutinin response to Brucella abortus strain 19. The possible reasons for these findings are discussed.     

Ontogeny of a specific high-affinity binding site for ovine placental lactogen in fetal and postnatal liver

Ovine placental lactogen (oPL) exerts actions in sheep and rodent fetal tissues that growth hormone (GH) does not. However, in postnatal tissues, both oPL and GH possess these activities. Although a high-affinity binding site for oPL in ovine fetal liver has been reported, some investigators believe this to be the GH receptor. It was our objective to discriminate between oPL and GH binding to fetal liver microsomes using competitive saturation analyses. Microsomal membranes from fetal liver (Days 60, 90, 105, 120, and 135 of gestation) and postnatal liver (1 wk of age) were incubated with increasing amounts of [¹²⁵I]oPL in the absence or presence of a 100-fold molar excess of unlabeled oPL. Saturable binding of [¹²⁵I]oPL was observed with fetal liver and postnatal liver microsomes. The K_d of the oPL-binding site in fetal liver was 122.1 ± 8.2 pM (mean ± standard error), and receptor concentrations remained relatively constant (9.8 ± 1.1 fmol/mg of membrane protein) across gestation. The highest concentration of oPL binding was detected in 1-wk postnatal liver microsomes (53.0 fmol/mg of membrane protein). Saturation analyses using [¹²⁵I]GH and [¹²⁵I] prolactin (PRL) were also conducted with fetal liver membrane preparations. Although specific binding for these two radiolabeled ligands was observed in control tissues, no specific binding was observed in fetal liver. These data are in agreement with earlier reports that a high-affinity binding site for oPL exists in fetal tissues. The fact that saturable binding could not be demonstrated for either GH or PRL with fetal liver microsomes contradicts recent suggestions that oPL is binding the GH receptor.     

The prevalence and epidemiology ofAnoplocephala perfoliata infection in Norway

The caecum and the adjacent 30 cm lengths of ileum and large colon of 201 horses from two different regions of Norway (Østlandet and Trøndelag) were examined for the presence ofAnoplocephala perfoliata. In all, 20% of the horses were infested with the cestode (27% in Østlandet and 7% in Trøndelag). The mean number of worms in infected horses from the two regions was 18 and 6, respectively.Information was obtained on the age, sex, breed, type of pasture and anthelmintic treatment after the grazing season for 183 of the 20 horses. The degree of infestation withA. perfoliata was not influenced by age, breed or sex. The odds ratio (confidence limits) for using permanent pastures that had been grazed by horses for at least the 5 last years in succession was 8.8 (3.2–24.4). There was a significantly higher prevalence ofA. perfoliata infestation in Østlandet (odds ratio 3.1 (1.1–9.1). The relatively low prevalence ofA. perfoliata infestation in Norwegian horses compared to the reported prevalences in other countries and the differences in the prevalence between Østlandet and Trøndelag are discussed. Gross pathological examination identified lesions such as mucosal thickening, hyperaemia and/or erosions. These lesions were found in all of the infected horses, compared with only 5% of the non-infected horses.Examination of faecal samples from 26 of the infected horses detected cestode eggs in only three cases. It was concluded that faecal examination is an inadequate method for the diagnosis ofA. perfoliata infestation.     

Systemic necrotizing vasculitis and glomerulonephritis in grower pigs in southwestern Quebec.

This purpose of this study was to describe the clinical features and the pathological findings of an unusual condition observed in pigs of a fattening unit in southwestern Quebec. Two of these pigs were submitted for complete postmortem examination. The disease was characterized by a systemic necrotizing vasculitis and an exudative and proliferative glomerulonephritis. In the skin, the vascular lesions produced a conspicuous papular dermatopathy with a characteristic distribution. Bacteriological and virological results were inconclusive. In the glomeruli, there were extensive granular complement deposits with scattered immunoglobulin M. Transmission electron microscopy did not reveal any dense deposits in glomerular basement membrane. The cause of this newly recognized and potentially lethal condition remains unknown, although histological and immunopathological observations suggest an immune-mediated process.     

Evaluation of the long-acting somatostatin analogue Octreotide in the management of insulinoma in three dogs

The response of dogs with insulinoma to surgical and medical management is variable, with the majority developing intractable hypoglycaemia. A long-acting somatostatin analogue, Octreotide (SMS 201–995; Sandostatin) has been useful in the management of hypoglycaemia in humans with insulinoma, and preliminary reports suggest a beneficial clinical response in dogs with insulinoma. The present study objectively evaluated Octreotide in the management of three dogs with immunohistochemically confirmed insulinoma. Octreotide had no benefit over placebo, and little effect on circulating glucose and insulin concentrations despite clearly detectable plasma concentrations of Octreotide. No clinical improvement was apparent in two dogs given Octreotide over a period of two and three weeks. These results contrast with the positive clinical responses noted previously and indicate that further placebo controlled, objective studies are necessary before clear statements on the treatment of insulinoma with Octreotide are made.     

ULTRASONOGRAPHIC FINDINGS IN CHOLECYSTOKININ-INDUCED PANCREATITIS IN DOGS

Pancreatitis can be induced in dogs by intravenous infusion of supraphysiologic doses of synthetic cholecystokinin octapeptide (CCK-8). Eight anesthetized female beagles were given either CCK-8 or saline in a randomized, blinded fashion and had abdominal ultrasonography to study the development of pancreatic lesions. Pancreatic lesions were apparent 2 hours after the start of CCK-8 infusion and included swelling, interlobular and subcapsular fluid accumulation and patchy hypoechogenicity of the gland parenchyma. CCK-8 had a variable effect on gallbladder emptying. No signs of biliary obstruction or duodenal lesions were identified. Dogs given CCK-8 had severe edematous pancreatitis at necropsy six hours after the start of the infusion. Compared to the oleic acid model of pancreatitis, CCK-8 infusion induces a rapid onset of pancreatitis and an ultrasonographic appearance that reflects diffuse edema of the gland. The short time-scale of the experiment may account for the relative absence of secondary lesions affecting the biliary tract or duodenum compared to the naturally-occurring disease.     

RADIOGRAPHIC IMAGING OF THE CANINE INTERCONDYLAR FOSSA

The intercondylar fossa is believed to play an important role in the pathology of cranial cruciate ligament rupture and therefore has received considerable attention in the last decade. Accurate radiographic imaging of the intercondylar fossa requires that the central x-ray beam pass through the center of the intercondylar "tunnel". The anatomy of the canine intercondylar fossa is similar to humans, however, the orientations of the intercondylar fossa's differ. Consequently, the positioning techniques described for humans are not appropriate for the dog. To pass through the center of the dog, intercondylar fossa, the central x-ray beam should be 12° (S.D. 1.7°) caudal from the femoral diaphysis in the sagittal plane and obliqued caudolateral to craniomedial 7° (S.D. 0.60°) (caudo78°proximo7° lateralcraniodistomedial oblique). Cross table positioning was used with the hip flexed and the radiograph cassette placed on the cranial surface of the stifle. However, superimposition of the tuber ischii and soft tissues caudal to the femur made 15° to 20° the best angle obtainable. There was not a significant difference (p = 0.17) in the notch width index between a 12° versus 20° angle of the central x-ray beam caudal to the femoral diaphysis, both with 7° of external rotation of the stifle. The notch width index of 0.252 obtained from radiographic measurements was not significantly different from measurements obtained grossly of 0.254 (n = 26; p = 0.69). Failure to oblique the central x-ray beam caused a significant (p = 0.0008) decrease in the apparent fossa width radiographically.