Desarrollo embrionario y postnatal de los sistemas visual yesquelético en aves precociales y altricialesestudio comparado

Abstract

Most of the studies in developmental biology using birds have been carried out in precocial species which, at hatching, show an advanced grade of maturity of the systems. This implies that after hatching, the nervous and the musculoskeletal systems are fully developed, and this allow them to interact with their environment in an appropriate way. On the other hand, altricial species born naked, blind and without locomotor competence, depending on parental care completely. In the present thesis it has been determined the differentiating pattern of the visual and skeletal systems of an altricial species, the zebra finch (Taeniopygia guttata) and it has been compared with those of two of the most frequently precocial species used in developmental biology, the quail (Coturnix coturnix) and the chick (Gallus gallus). It has been used histological and histochemical techniques. These techniques allow us to determine the onset of cell differentiation in the retina of these species, the emergence of the different layers and the maturity process of each cell type in this region. Moreover, it has been stablished the onset of the osteogenic processes and its progression along the embryonic development and postnatal stages.