Innovative Animal Model of DSS-Induced Ulcerative Colitis in Pseudo Germ-Free Mice.

The aim of this study was to investigate the use of a standardized animal model subjected to antibiotic treatment, and the effects of this treatment on the course of dextran sodium sulphate (DSS)-induced colitis in mice. By decontamination with selective antibiotics and observation of pathogenesis of ulcerative colitis (UC) induced chemically by exposure of mice to various concentrations of DSS, we obtained an optimum animal PGF model of acute UC manifested by mucin depletion, epithelial degeneration and necrosis, leading to the disappearance of epithelial cells, infiltration of lamina propria and submucosa with neutrophils, cryptitis, and accompanied by decreased viability of intestinal microbiota, loss of body weight, dehydration, moderate rectal bleeding, and a decrease in the selected markers of cellular proliferation and apoptosis. The obtained PGF model did not exhibit changes that could contribute to inflammation by means of alteration of the metabolic status and the induced dysbiosis did not serve as a bearer of pathogenic microorganisms participating in development of ulcerative colitis. The inflammatory process was induced particularly by exposure to DSS and its toxic action on compactness and integrity of mucosal barrier in the large intestine. This offers new possibilities of the use of this animal model in studies with or without participation of pathogenic microbiota in IBD pathogenesis.

Enteric protozoa of cats and their zoonotic potential-a field study from Austria.

Domestic cats can be infected with a variety of enteric protozoa. Genotyping of protozoan species, especially Giardia as the most common, can improve assessment of their relevance as zoonotic agents. For an overview on the occurrence of feline enteric protozoa, 298 faecal samples of cats from private households, catteries and animal shelters in Austria were collected. All samples were examined by flotation and using a rapid test for Giardia (FASTest). For the detection of Tritrichomonas blagburni, freshly voided faeces (n = 40) were processed using a commercial culturing system (InPouch TF-Feline). Genotyping was done at the ß-giardin gene loci (each sample) and triosephosphate isomerase gene loci (positive samples) for Giardia and at the 18S rRNA gene (positive samples) for Cryptosporidium. Thirty-seven samples (12.4%) were positive for Giardia by flotation and/or using a rapid test. Cryptosporidium was present in 1.7%, Cystoisospora in 4.0%, Sarcocystis in 0.3% and T. blagburni in 2.5% of the samples. Genotyping revealed Giardia cati, the potentially zoonotic Giardia duodenalis and Cryptosporidium felis. Most of the infected cats had no diarrhoea. Cats from shelters were significantly more often infected than owned cats (p = 0.01). When comparing Giardia detection methods, the rapid test had a higher sensitivity than flotation. Polymerase chain reaction (PCR) results were mostly independent from the other two tests.