Anatomical and histopathological researches in experimental infection with Prototheca algae in mice.

Abstract

In order to realize this study, three BALB mice gr oups were used: one inoculated with P. zopfii , one with P. wickerhamii suspension and one control group. Each infected gr oup was constituted of twelve animals, 2 months old, with a n approximate body mass of 20 g. Both Prototheca species: one referent strain Prototheca wickerhamii (RE-4608014 ATCC 16529) and one Prototheca zopfii isolate (from cow mastitic milk sample), were cult ured in glucose broth medium, 48 hours, at 37oC. Except control group, each animal was i.p. inoculat ed with 0,1 ml of live alga suspension (approximately 10 7 CFU/ml). Two control mice were i.p. inoculated with 0,1 ml of sterile broth media. Although any clinical disease sign was not observed in 10, 15 and 20 days post - infestation, for both inoculated groups, four mice were slaughte d. Macroscopic lesions caused by Prototheca algae were represented by granuloma and piogranuloma found in different internals as confirmed by identification of organism by staining with periodi c acid-Schiff (PAS) and culture. So appreciated illness severity we utilized a score system in orde r to obtained a lesional systemic score for each animal. We appreciated: limph nodes reaction, the p resence or absence of granuloma in skin, liver, pancreas, diaphragm, kidney, spleen and intestine. The data were statistically process using t test. In group inoculated with P. zopfii the lesions were more severs than those evidenciat ed in P. wickerhamii infected group.