A genetic polymorphism study was performed in coccidia from the rabbit. A comparative analysis of the RAPD (random amplified polymorphic DNA)-generated fingerprints, using 11 arbitrary primers, was carried out (1) in nine Eimeria species (E. intestinalis, E. magna, E. piriformis, E. flavescens, E. vejdovskyi, E. coecicola, E. perforans, E. exigua, and E. media) and (2) in two strains of E. intestinalis and four strains of E. media originating from different geographic areas. For each of these four strains of E. media, three lines deriving from the multiplication of a single oocyst were compared. All the primers tested yielded about ten amplified fragments. The profiles obtained differed considerably according to the species; thus, it was not possible to establish a phylogeny. On the other hand, species-specific fingerprints were observed, showing that RAPD assays might be useful for diagnosis. In E. media, analysis of the RAPD products showed weak differences between each of the four strains but nevertheless allowed differentiation of the lines deriving from the multiplication of one oocyst. Similar results were obtained with three methods of analysis: correspondence analysis, the hierarchical unweighted pair-group method with arithmetic averages (UP-GMA), and parsimony analysis. RAPD proved to be a useful technique for these intraspecific studies.

No abstract

Summary :Although vertical transmission of Pneumocystis in human or animal hosts has often been suspected, no evidence demonstrating this infection route has been furnished until now. This widespread parasite is constantly found in the lungs of rabbits, which spontaneously develop a benign pneumocystosis at weaning.However, the infection source, the method of entry of Pneumocystis organisms into the rabbit and when this mammal is infected, remain to be known. As a few parasites have been

No abstract

Airborne transmission of Pneumocystis carinii has been established, but the infective form and the sources of infection remain unknown. Animal models for studies of P. carinii have previously been limited to immunosuppressed rodents; however, this study was performed with nonimmunodepressed P. carinii-free rabbits. This study was aimed at determining (i) the delay between inoculation of animals (day zero [D0]) and the onset of contagiousness and (ii) the end of contagiousness of these animals (donors). Five-week-old rabbits were used as contact animals and were housed with the donors. The cohabitation periods were for 4 or 5 days from D0 to D4, D4 to D8, D8 to D13, D13 to D18, and D18 to D22. The highest parasite burdens were observed in contact animals housed with donors from D8 to D13 or D13 to D18. This period (8th to 18th day following the day of inoculation of donors) might correspond to the highest phase of contagiousness of donors.

No abstract

No abstract

Cultivation of Pneumocystis carinii from rabbit onto cell monolayers was intended. Three cell types were used: rat lung derived cell line L2 and canine kidney derived cell line MDCK, and primary epithelial rabbit lung cells derived from 20 days old foetuses. These primary cells were also immortalized by transfection of the coding sequences for the large and small T antigens of the SV40 virus. P. carinii were extracted from lungs of corticoid treated young rabbits and were purified on Ficoll. In vitro development of P. carinii was assessed by counting the number of attached parasites on cells after staining. No development was observed on L2 nd MDCK cell lines. On the contrary, a development was observed on rabbit derived cells with a threefold increase of attached parasites on the third day of culture. Immortalized cells allowed also multiplication of attached P. carinii. These results are similar to those obtained with culture of rodent P. carinii onto cell monolayers.