SYMPOSIUM - CURRENT ADVANCES IN AVIAN EMBRYOLOGY AND INCUBATION AVIANMODELS IN DEVELOPMENTAL BIOLOGY

The avian embryo is uniquely amenable to experimental manipulation. Th e most widely used models are chimeras resulting from heterotopic or o rthotopic exchanges of rudiments between chick and quail embryos, acco rding to Le Douarin's technique (1969). Cell migrations and fates are traced in these chimeras either through the identification of quail ce ll nuclei stained for DNA or by means of monoclonal antibodies that re cognize a particular lineage in only one of the two species. The ontog eny of the hemopoietic and endothelial lineages, as enlightened throug h appropriately designed chimeras, is reviewed in the present article. Homologies recently disclosed in mouse and human embryo are emphasize d. Finally, the possibilities afforded by retroviral somatic transgene sis in the avian embryo will be envisaged.