Histiocytic ulcerative colitis in a French Bulldog

A case of histiocytic ulcerative colitis (granulomatous colitis) in a one–year–old female French Bulldog is described. Until now this disease has been described only in the Boxer breed.
The dog had an increased frequency of defaecation and the faeces contained blood and mucus. Colonoscopy showed some irregularities and a few haemorrhages in the mucosa of the caudal part of the colon. At a distance of approximately 25 cm from the anus there was a stricture caused by rigidity of the colon wall. Radiographic examination revealed marked shortening of the colon. There was also narrowing of the midpoint of the descending colon in some radiographs, but the colon appeared to be fully distensible when filled with barium. Histologically, periodic acid–Schiff (PAS)–positive staining histiocytes were found in biopsy and autopsy specimens from the colon.     

Eosinophilic gastroenteritis complicated by partial ruptures and a perforation of the small intestine in a dog

A 2-year-old male Bouvier de Flandres was admitted because of muco-haemorrhagic diarrhoea of three weeks duration. Radiographic examination revealed signs of gastrointestinal perforation with peritonitis and ileus. Laparotomy revealed a severely changed intestine with longitudinal ruptures of the external part of the wall, and jejunal perforation causing an acute peritonitis. The mesenteric lymph nodes were enlarged. A diffuse eosinophilic gastroenteritis and lymphadenitis were found at autopsy with granulomatous lesions in the oesophagus, stomach and intestines.     

Pyloric stenosis caused by hypertrophic gastritis in three dogs

Hypertrophic gastritis of the pyloric antrum is described in an 11-year-old female poodle, a 14-year-old male Maltese terrier and a 13-year-old male mongrel. The dogs suffered from chronic vomiting. Gastroscopic examination revealed mucosal proliferations in dogs 1 and 3. Radiographic examination showed signs of pyloric obstruction in all three dogs. Contrast studies demonstrated thickenings in the region of the pylorus in dogs 1 and 2. Laparotomy was done in all three dogs: in dog 1 a gastro-duodenostomy was performed and in dogs 2 and 3 the circularly thickened mucosa was resected. The mucosa of all three dogs showed hypertrophic gastritis, chiefly due to foveolar hyperplasia, and round cell infiltration, especially in the superficial layers. Herniation of mucosal glands through the muscularis mucosae was found in dog 1. Dogs 1 and 2 recovered well and vomiting ceased. Dog 3 continued to vomit because of a pyloric stenosis, mainly due to muscular hypertrophy.     

Homothallism in Peronospora viciae f.sp. pisi and the effect of temperature on oospore production

Monoconidial cultures derived from seven P. viciae f.sp. pisi isolates, obtained from different countries, were able lo produce oospores, Apparently, these isolates were homothallic. Oospore production of one isolate was studied at 5, 10, 15 and 20°C in systematically colonized shoots, and in local lesions on leaflets, stem parts and pods of the pisum sativum cv. Kelvedon Wonder. The number of oospores produced per gram systemically colonized tissue increased with temperature. In lesions of leaflets and of stem parts, including tendrils, petioles and main stem, most oospores were produced at 20°C. At 10°C, a few oospores were found in stem parts but none in leaflet lesions. At 5° C, no oospores were formed at all. In pods, moe oospores were produced at 15 and 20°C than at 10°C, but the numbers of oospores was smaller than in the other plant parts. Oospores formed at lower temperatures were larger than those formed at higher temperatures. At 20°C, similar oospore densities were found in leaflet lesions of three cultivars widely differing in resistance to downy mildew.     

Extraction of oospores of Peronospora viciae from soil

A method for the extraction of oospores of Peronospora viciae from soil is described. Approximately 75% of the oospores added to silty clay loam and loamy sand soil samples were recovered. Percentage recovery was independent of oospore density. This extraction method did not affect viability as determined by the tetrazolium bromide test and a germination assay and may therefore be used to study survival of oospores. Numbers of oospores extracted from soil samples taken from seven fields naturally infested with oospores of P. viciae f.sp. pisi ranged from 2 to 21 oospores per g soil. Oospore density was not significantly correlated with disease incidence as determined by a bioassay.