Hemostatic defects associated with two infusion rates of dextran 70 in dogs.

We investigated changes in hemostatic function after infusion of 6% dextran 70 (high molecular weight dextran) at 2 rates. Six healthy dogs underwent 3 regimens: 20 ml of dextran/kg of body weight administered in 1 hour (trial A), 20 ml of dextran/kg administered in 30 minutes (trial B), and 0.9% sodium chloride solution as a control administered over 1 hour to achieve hemodilution equivalent to that for 20 ml of dextran/kg (trial C). Before and at 2, 4, 8, and 24 hours after the start of trials A and B, we measured PCV, total solids (TS) concentration, amount of von Willebrand factor antigen (vWf:Ag), factor VIII coagulant activity (VIII:C), prothrombin time, activated partial thromboplastin time (APTT), platelet retention in a glass bead column, and buccal mucosa bleeding time (BMBT). Values were not obtained at 8 and 24 hours for trial C. Saline-induced changes in hemostasis were significant (P less than 0.05) from baseline throughout the sample collection period. Significant differences (P less than 0.05) between trial A and control were observed for vWf:Ag, VIII:C, BMBT, APTT, TS, and PCV values at 2 hours, and for VIII:C at 4 hours. Significant differences (P less than 0.05) between trial B and control were observed for APTT, TS, and PCV values at 2 hours, and for vWf:Ag, VIII:C, BMBT, APTT, TS, and PCV values at 4 hours. During trials A and B, mean values of analytes infrequently deviated from reference intervals, and clinical signs of bleeding were not observed in any dog.(ABSTRACT TRUNCATED AT 250 WORDS)     

USE OF 123IODINE METAIODOBENZYLGUANIDINE SCINTIGRAPHY FOR THE DIAGNOSIS OF A PHEOCHROMOCYTOMA IN A DOG

A 13-year-old neutered female Yorkshire terrier presented with a history of progressive episodic weakness and disorientation of 4 months duration. Physical and neurologic examinations were normal at presentation. Abdominal ultrasound revealed a mass involving the right adrenal gland. Standard planar scintigraphy was performed at 4, 18, and 24 hours after intravenous injection 185 MBq (5mCi) of ¹²³I-labeled metaiodobenzylguanidine (¹²³I-MIBG). An area of focal intense uptake was identified in the area of the right adrenal gland. A pheochromocytoma was confirmed histologically after surgical excision.     

An enzyme immunoassay to measure canine circulating fibronectin

A competitive enzyme immunoassay has been used to detect and quantitate fibronectin in canine plasma. In this test, purified fibronectin, bound to microtiter plates, competes with plasma fibronectin for the conjugated antibody, rabbit-anticanine, fibronectin-horseradish peroxidase. The assay could detect fibronectin in purified standards from 58 ng/ml to 580 microgram/ml. The range of 1-100 microgram/ml was linear for plasma samples diluted 1:10, allowing samples with fibronectin concentrations from 10-1000 microgram/ml to be easily measured by this method. The mean normal fibronectin concentration of 132 dogs, by this method, was determined to be 320 +/- 74 microgram/ml.     

Insulin-secreting islet cell tumors: establishing a diagnosis and the clinical course for 25 dogs

Twenty-five dogs with insulin-secreting neoplasms of the pancreas were studied. The diagnosis in each case was determined by histologic evaluation of pancreatic tissue obtained at surgery. The breed distribution revealed that German Shepherd Dogs, Irish Setters, and Collies were most commonly represented. Physical examination, complete blood counts, serum biochemical analysis, and urinalysis were of little diagnostic value, aside from the finding of hypoglycemia in 21 of 25 dogs. Radiographs of the thorax and abdomen were noncontributory to the ultimate diagnosis. Prior to surgery, fasting immunoreactive insulin concentrations and blood glucose concentrations were studied. Insulin:glucose ratios, glucose:insulin ratios, and amended insulin:glucose ratios were determined from the insulin and glucose concentrations in a single blood sample in each of 28 trials. In addition, glucagon tolerance tests were performed on 12 dogs. The amended insulin:glucose ratios proved to be the most reliable for diagnosis. Pancreatic masses were evident at surgery in 23 of 25 dogs; the remaining 2 dogs had microscopic evidence of an islet cell tumor. Nineteen of the islet cell tumors were carcinomas and 6 were simply described as "islet cell tumors." The mean life expectancy after surgery was 12.3 months. Treatment for malignant islet cell tumours included frequent feeding glucocorticoids, and diazoxide.     

Experimental Neospora Caninum Infection in Pregnant Dairy Heifers Raises Concentrations of Pregnancy‐Associated Glycoproteins 1 and 2 in Foetal Fluids

Plasma concentrations of PAG‐1 are used for pregnancy diagnosis and as a marker of placental/foetal well‐being, while those of PAG‐2 may be an indicator of abortion risk in Neospora caninum‐infected cows. Studies have shown that N. caninum infection modifies PAG‐1 and PAG‐2 patterns in maternal blood plasma. However, no prior work has examined the effects of N. caninum infection on concentrations of PAGs in foetal fluids. In this study, PAG‐1, PAG‐2 and pH levels were determined in the amniotic and allantoic fluids of foetuses collected at 152 days of gestation from control uninfected dams and from dams experimentally infected with N. caninum on Day 110 of gestation. Foetal fluids from infected foetuses had significantly higher PAG‐2 concentrations (p = 0.026) and pH values (p = 0.02) than fluids from non‐infected foetuses. In infected foetuses, significantly higher concentrations of PAG‐1 (p < 0.001) and PAG‐2 (p < 0.001) were detected in fluid samples showing antibodies against N. caninum than those without antibodies. Moreover, pH values were significantly higher (p = 0.011) in foetal fluid samples with antibodies than in samples from non‐infected foetuses. In conclusion, this is the first report on the effect of N. caninum infection on PAG levels in foetal fluids. Our results indicate that following the experimental infection of dams with N. caninum on Day 110 of gestation, foetal fluids collected from the infected foetuses of these dams featured higher PAG‐1 and PAG‐2 levels and pH values than fluids from non‐infected controls, provided that the samples tested showed the presence of antibodies. The clinical implications of these findings are that following infection with N. caninum, most cows will experience some level of placental damage and that this injury correlates with foetal fluid PAG levels and pH.     

Reproductive biology of pond reared Nile tilapia, Oreochromis niloticus L.

The reproductive performance of female Nile tilapia, Oreochromis niloticus L., reared in ponds under tropical conditions was studied. The experiments used stock matured to the age of 2–4 months and a size of 30–50 g. Oocyte development proved a better indicator for the determination of the size at first maturation than the development of the gonado-somatic index. The Nile tilapia became ‘stunted' in the sense that early breeding took place, but the somatic growth of the stock still continued. This result indicates that the earlier breeding of Nile tilapia is not a real bottleneck for the expansion of this production sector. No relationship was found between the condition factor and the size at first maturation or the relative fecundity. This led to the conclusion that aggravation of the living conditions is not a major cause of earlier breeding of pond-reared O. niloticus.