O ducto epididimário (DE) de codorna doméstica mostrou, ao longo do ano, variabilidade pequena, porém muito expressiva no outono, o qual corresponde à fase quiescente do ciclo testicular anual. A morfologia do DE na primavera foi, em termos, similar à verificada no verão e inverno. Nestas fases notaram-se aumento significante do calibre tubular do DE; estocagem intraluminal de espermatozóides e ocorrência de mitocôndrias, lamelas do RE, vesículas variáveis quanto à forma, dimensões e conteúdos e presença de alguns lisossomos localizados, principalmente, no citoplasma apical das células principais (P), no epitélio epididimário. Estas características ultra-estruturais das células P parecem ser indicativas da ocorrência de processos ativos de endocitose e de secreção micromerócrina. A quiescência outonal foi caracterizada pelo aspecto anfractuoso do DE; ausência de espermatozóides e pouco material intraluminal, observados à microscopia de luz. Características ultra-estruturais degenerativas foram verificadas ao nível do citoplasma supranuclear das células P epididimárias no outono.

Small but expressive variability was noted on the epididymidis duct (ED) of domestic quail along the year, with more evidence in autumn of the quiescent phase of the annual testis cycle in this species. Spring features of ED had a general similar pattern in summer and winter. They were characterized by enlargement of epididymis tubule, storage of spermatozoa into the luminal compartment and presence of mitochondria, ER lamellae, several variable vesicles, and lysosomes localized mainly on the apical cytoplasm of principal cells (P) of the epididymal epithelium. These P cells features indicated a process of endocytosis and perhaps protein secretion. Autumn quiescence was marked by a convolute pattern of the epididymis tubule, lacking of spermatozoa and small amount of exfoliate heterogeneous material inside the luminal compartment at light microscopy. Ultrastructural degenerative features mainly apical cytoplasmic debris were seen in the supranuclear cytoplasm of lining P cells.

Structural features of segmental parts of the aorta of rabbit were studied by light, scanning and transmission electron microscospies. The variabilities in architectural composition and thicker of the vascular coats as well as in vascular diameters at the ascendent (T2-3 level), thoracic (T6-7 level) and abdominal (L5-6 level) segments of the aorta were verified. Morphological features such as presence of intimal folds; occurrence of medial myo-elastic connections with segmental variations in the number of elastic lamellae, whose relative number was major in the ascendent and thoracic parts relatively to the abdominal part, and predominance of a network of stromal elements (connective fibers) in the adventitia were characterized. Also, the morphological findings were discussed at histophysiological base, because small but significative segmental differences were observed in the mural aortic structure of the rabbit

La estructura microscópica de la aorta de conejo fue estudiada, con recursos de microscopías óptica, electrónica de barrido y de transmisión, en las porciones ascendente torácica y abdominal, observándose variaciones morfométricas en el diámetro vascular y espesor de las capas de la pared aórtica. Los valores obtenidos fueron, generalmente, mayores en la porción ascendente. Características estructurales de la pared vascular fueron descritas, destacándose la presencia de pliegues en la túnica íntima; la formación de conexiones mioelásticas en la túnica media, variaba el número de lamelas elásticas en distintos segmentos, siendo mayor en las porciones torácicas ascendente y descendente, en relación a la porción abdominal. En la túnica adventicia predominaban las fibras del conjuntivo, dispuestas de forma variada, constituyendo una red. Los resultados fueron discutidos en términos morfofuncionales, teniendo presentes las pequeñas, pero significativas, variaciones segmentares observadas en la estructura de la pared aórtica de conejo