Some expressive differences were noted on the distal efferent ducts (DED) morphology in domestic quail of the Italian variety along the year. The birds were maintained on experimental captive breeding along two consecutive years, before the morphologic studies. Morphologic differences on the DED had been more evident in spring and autumn respectively, the active and quiescent phases of the annual testis cycle. Variability more expressive was noted among the principal (P) and ciliated (C) epithelial cells and in tubular diameters of DED, during the two focused seasons. Spring features of DED were marked by relative enlargement of the passageways, with similar results in summer and winter, and characteristic organelle development on the apical cytoplasm of P cells, allowing to conclude presence of active process of endocytosis. Autumn quiescence was marked by an enfolding pattern of all the tubular passageways, lacking of spermatozoa and small amount of heterogeneous material inside their luminal compartments, followed by presence of ultrastructural degenerative features in apical cytoplasm of P cells and C cells in DED passageways. Tubular features verified in DED during winter and summer were minor and similar to those described in spring. Summer and winter were respectively considered the recrudescent and regressive phases of the testis cycle in these species, based on the spermatogenesis cycle analysed in all the seasons of the year as well as on the base the morphologic features here found.
efferent distal ducts; morphology; morphometric data; Italian domestic quail
