Worm Breeder's Gazette 5(1): 30
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
In our laboratory C. elegans, Bergerac strain,has been routinely cultivated in xenic conditions on nutrient agar since several years. Different populations were maintained separately. The intestinal tractus of the worm was studied cytologically by the 'frottis' technique followed by Feulgen reaction. We have distinguished two populations categories. Results are homogeneous in each of them what ever the larval and adult stages considered and are similar after 100 generations. - First category (majority of populations) - The intestine nuclei alone are Feulgen positive, intestine lumen is clear. - Second category - Feulgen positive material is found throughout the intestine lumen with the same intensity from the very anterior region to the rectum. This Feulgen positive material when observed under Nomarski differential interference contrast optics in the light microscope appears to be constituted by many thousand particles. Their size is just larger than resolution power allowed by microscope. These Feulgen positive particles are neither revealed in Nematodes cultivated in axenic conditions, nor when the hydrolysis is omitted during Feulgen reaction. All these results allowed us to consider that the positive Feulgen material originates in the staining of bacterial chromosomes. So, one or more bacteria strains would be able to colonize the intestine lumen of this Bergerac sub population and to be tolerated by the worm even in large amounts. This result is interesting in the perspective of better knowledge of Nematode-bacteria relations. Which and how much bacteria species are implicated in the nutritional requirements? Are these bacteria symbiot or not?