A recent observation concerning the phallus of the tinamou Nothura maculosa was the presence of cells resembling plasma cells within the epithelium of the fixed tubular portion. Owing to this unusual location of plasma cells, we studied the phalli of the tinamous N. maculosa and Rhynchotus rufescens to confirm the occurrence of intraepithelial plasma cells and to evaluate the seasonal variation in these cells. Abundant plasma cells were found within the epithelium of the fixed tubular portion of the phallus but not in the evertible portion. Migration of plasma cells from the adjacent connective tissue through the basement membrane and between the epithelial cells was frequent. Some plasma cells exhibited a rough endoplasmic reticulum with variable cisternal distension, containing fine, slightly electron-dense, granular material suggestive of immunoglobulin accumulation. An expressive increase of more than 800% in the number of intraepithelial plasma cells was found during the breeding season compared to the non-breeding season. By establishing the occurrence of intraepithelial plasma cells in the phallus and their seasonal variation, the results contribute to a better understanding of the role of these cells in the mucosal immune system of the reproductive tract of male birds.

Epididymal lithiasis (EL) histopathology is described using light and electronic microscopy in roosters (Gallus gallus domesticus) naturally affected by EL in Minas Gerais, Brazil. The histologic and morphological changes by EL in roosters was performed regarding cellular and subcellular details through light and electron microscopy. Efferent ductules epithelium lysosomal increase in size and numbers, membrane rupture, cellular vacuolation, ciliary loss, basal membrane degeneration, inflammatory reaction with mononuclear infiltrations, edema, epithelial and vascular endothelium losses were described. All industrial and freerange chickens showed EL in varying degrees in the efferent ductules (ED). However, ED altered areas did not correlate with the presence of luminal stones. Non-ciliated ED epithelium cells presented several atypically large lysosomes. Plicae loss and basal vacuoles were observed in the epithelium of dilated regions. Cellular cilia loss and apical cytoplasmic membrane rupture resulted in leakage of the cytoplasmic contents to the ED lumen, and ED epithelium desquamation occurred with or without lesion to the basal membrane. Basal membrane alterations were associated with profound sub-epithelial connective tissue damage. Aggregations of desquamated epithelium and spermatozoa were seen in the lumen of ED and compact aggregates were considered the basis for calculi formation. The widespread occurrence and high severity of EL lesions are indicative of the importance of EL as a cause of infertility in male chickens.