Contrast Radiography of the Upper Gastrointestinal Tract in the Dog: A Comparison of Micropulverized Barium Sulfate and U.S.P. Barium Sulfate Suspensions in Clinically Normal Dogs

Abstract— Sixty upper gastrointestinal radiographic examinations were done on five littennate mongrel dogs to compare a commercial micropulverized barium sulfate suspension and a hand-mixed U.S.P. barium sulfate suspension. Two different fasting times and three different dosage rates were used. Small bowel transit times were influenced significantly (p>0. 05) by the type of contrast agent employed, but not by the volume of medium or by the duration of fasting. Mucosal pattern, loop visibility, and continuity of contrast material were superior when the commercial preparation was used. Recommended dosages were 8–12 cc/kg for small and medium-sized dogs and 5–7 cc/kg for large dogs, using the commercial agent, or an equivalent concentration of U.S.P. barium sulfate suspension. Résumé—Soixante examens radiographiques du tractus gastro-intestinal supérieur ont été effectués sur 5 portées de chiens métis dans le but de comparer une suspension commerciale de sulfate de barium à l'état micropulvérist et une suspension de sulfate de barium U.S.P. (pharmcacopée des Etats Unis) mélangée à la main. On a utilisé deux temps de jeûne différents et illisible gammes de dosage. Les temps de transit courts étaient influencés de facon significative (p.o, 5) par le type d'agent contrastant utilisé mais non par le volume de milieu ou par la durée de jeûne. L'image de la mu-queuse, la visibilité des anses intestinales, la continuité du moyen de contraste étaient meilleures aprés utilisation de la préparation commerciale. Les doses recommandées sont 8–12 cc/kg par les animaux de petite et moyenne taille et de 5–7 cc/kg pour les gros chiens, aussi bien avec la préparation commerciale qu'avec une concentration équivalente de suspension de sulfate de bariun U.S.P. Zusammenfassung— Sechzig Röntgenuntersuchungen des oberen Gastrointestinaltrakts wurden an fünf Bastardhunden des gleichen Wurfs durchgeführt, um eine mikropulverisierte Barium-sulfatsuspension des Handels mit einer handpräparierten USP-Bariumsulfatsuspension zu vergleichen Zwei verschiedene Fastenzeiten und drei verschiedene Dosierungen wurden angewendet. Die Durchgangszeiten durch den Dünndarm wirden wesentlich (p<0,05) vom Typ des verwendten Kontrastmittels, aber nicht vom Volumen des Mediums oder der Dauer des Fastens beeinflusst. Das Schleimhautrelief, die Erkennbarkeit der Darmschlingen und die Kontinuierlichkeit des Kontrastmittels waren bei Venvendung des Handelspräparats hervorragend. Die empfohlenen Dosen sind 8–12 ml/kg für kleine und mittelgrosse Hunde und 5–7 ml/kg fur grosse Hunde bei Venvendung des Handelspräparats oder einer äquivalenten Konzentration der USP-Bariumsulfatsuspension.     

Multi‐seasonal field release and spermatization trials of transgenic hypovirulent strains of Cryphonectria parasitica containing cDNA copies of hypovirus CHV1‐EP713

Three indigenous field strains of the chestnut blight fungus, Cryphonectria parasitica collected in 1996 from a test site in the Meshomasic State Forest, Connecticut, USA, were engineered to contain a chromosomally integrated full‐length infectious cDNA copy of the severe, virulence‐attenuating hypovirus CHV1‐EP713. These transgenic hypovirulent strains were introduced into the test site after it had been clear‐cut, as sprayed conidia in multiple applications over 4 years, beginning in 1997. Evidence was obtained for cytoplasmic transmission of cDNA‐derived hypovirus RNA and for recovery of transgenic strains from canker tissue of the spray‐treated trees. However, there was no indication of spread of transgenic strains or cDNA‐derived viral RNA to the control plot or outside the treatment plot. A single transgenic C. parasitica isolate was identified from a total of 156 isolates recovered from 1330 insects representing five insect orders. Only 2.6% of the 1082 C. parasitica bark isolates recovered during the course of this study were vegetatively compatible with the untransformed input strains. Transgenic ascospore progeny were produced by 40% of the perithecia collected in 1999 and by only 7.3% of the perithecia collected in 2000. A concurrent field release study performed in the Monongahela National Forest in West Virginia in 1998 and 1999 with transgenic hypovirulent strains constructed with the same CHV1‐EP713 cDNA‐containing plasmid identified seasonal application dates and delivery methods that resulted in very high levels of transgenic ascospore production. Results of the combined field release studies are discussed in terms of requirements for improved formulations and delivery methods and the importance of balancing ecological fitness and virulence attenuation.     

Two cases of paraprostatic cysts in castrated male dogs

Two castrated male dogs presented for evaluation of tenesmus. Presurgical evaluations included complete physical examinations, serum biochemistry, abdominal ultrasonography, and MRI (case 2 only). Paraprostatic cysts were diagnosed in both cases based on the results of abdominal ultrasonography, MRI, and histopathology of tissue samples obtained during exploratory laparotomy. To the authors' knowledge, the two cases presented herein are the first documented cases of paraprostatic cysts that developed after castration in male dogs. Paraprostatic cysts should be considered in the differential diagnoses for castrated male dogs with prostatic disease.