The domestic dove Columba livia (Gmelin, 1789) is a species well adapted to Brazil and the study of its reproductive biology is part of a broad research project on birds. This essay describes the morphological aspects of the cloaca of female Columba livia, describing compartments lengthwise starting from the head such as the coprodeo, urodeo and proctodeo limited by mucosal folds. Each compartment of the cloaca presents its own morphological characteristics which differ one from the other in form, height and position of mucosal projections, kinds of tissues, presence and histological aspects of glands, presence of lymphonodus. The rectum opens into the coprodeo, the ureter opens into the oviduct and the cloacal sac opening into the proctodeo. Histochemical studies have shown the presence of glycoproteins in tissue cells and gland cells on the three segments of the cloaca.

The Columbina talpacoli (Temminck, 1811) dove, a small bird of the order Columbiformes, is abundant throughout Brazil and interacts closely with city inhabitants. This study describes the morphological and histochemical aspects of the epididymal region and ductus deferens of this species, comparing them with those of other bird species studied. It is believed that a better understanding of the reproductive biology of Columbina talpacoli could help to solve the ecological and sanitary problems involving these birds.

Numida meleagris (Linné, 1758) is an african bird that was brought to Brazil. As the bird adapted to the climate of this new habitat and spread ali around the country, it is nowadays part of our avifauna. The present study continues topographic and morphofunctional researches on the female genital apparatus of this species, since it describes histological and histochemical aspects of magnum, a segment of oviduct. Magnum was dissected and processed according to routine and histochemical staining procedures to detect glycogen and mucous substances in the epithelial tissue and mucous glands. Besides focusing morphological aspects, the study compares the data obtained with those of other species aiming to contribute to the enlargement of the knowledge on reproductive biology of brazilian birds what may be important to make their biological control easier.

The study of the female genital system of Columba livia (Gmelin, 1789) is part of the research on the reproductive biology of Brazilian birds. This work describes the morphological aspects of the ovary of Columba livia, as well as the histological differences observed in the ovarian follicles during the ovocyte maturation process. Ten Columba livia females were studied, whose ovaries had been dissected, fixed in Bouin and Helly solutions, and histologically processed for staining (Hematoxylin-Eosin; Gomori's trichromic and Weigert's technique and Gomori's technique for connective tissue fibers). The ovary has an irregular surface, is located in the abdominal cavity, and relates to the cranial portion of the left kidney and caudal extremity of the left lung. Histological examination shows that the ovary is covered with simple cubical epithelium, underlined by loose connective tissue that continues internally, surrounding the follicles. The ovarian follicles were described, in their different stages of development, with basis on the morphological changes occurring in the ovocyte and in the layers that surround it, in each phase of maturation. Among the follicles, groups lof cells of two distinct types, surrounded by connective tissue, are observable: clear cells with a spherical nucleus, and acidophilic cells with a slightly elongated nucleus. The studies of the ovary of Columba livia reveal histological similarities between this species and Columbina talpacoli (Temminck, 1811), whose ovaries were examined by Ribeiro et al. (1991).

Known as "domestic dove", the Columba livia (Gmelin, 1789) is a columbidae species widely distributed in Brazil, whose reproductive biology has been studied by many researchers. The testes of 12 Columba livia males were collected and prepared for histologic examination under an optical microscope, the results of which were analysed and photographed. The tunica albuginea that covers the testes consists of a thick, not very cellular layer of dense connective tissue. Groups of interstitial cells with typical morphological appearance and surrounded by loose, well vascularized connective tissue are observable within the organ, between the seminiferous tubules. The seminiferous tubules are thick, intensely wound and, when seen in cross section, show Sertoli cells and spermatogenic lineage cells in different stages of development. These include spermatogonia (type A, clear; type A, dark; and type B), spermatocytes I and II, spermatids, and a large number of spermatozoons. Similarities are found between the histological findings described and those reported for the testes of Columbina talpacoti (Temminck, 1811).

General histology of small intestine (duodenum and jejunum) and the large intestine (colon and cloaca) of C. c. yacare (Daudin, 1802) Crocodilia-Reptilia. A comparative description is made of the histology of the small and large intestine of C. c. yacare. In all segments mucosa, submucosa, muscularis and serosa tunics were observed. The duodenum as very long villi, wich are well-developed and attached together to form irregular transverse ridges, covered with simple columnar epithelium with marginal and goblet cells. In the jejunum, the villi are shorter and less frequent. The colon as few folds, covered with the same epithelium; the lamina própria contains straight tubular glands with absortive cells, goblet and Paneth cells. The cloaca is very complex, with three well-defined regions: coprodeum, urodeum and proctodeum. In the coprodeum, the wall is folded, less muscular and the thin mucosa is covered by an epithelium with a few basal cells and mucosal cells. The urodeum as an additional external muscular tunic, with striated muscle fibers and a stritifield cylindrical epithelium with goblet cells. The proctodeum includes the free part of the penis in the male and, laterally, the ducts of a pair of holocrine cloacal glands. Near the opening of the ducts, the epithelium changes to a squamous keratinized type.