The surface features of the epithelial lining of the ducts of the epididymis of the ostrich (Struthio camelus)

The luminal appearance of the various ducts of the epididymis of the ostric h was studied by scanning electron microscopy in tissues fixed by immersion in glutaraldehyde. The ductal types were similar to those previously descr ibed for some other species of birds. Numerous short microvilli, as well as a single cilium, projected from the apical surface of the rete testis cell . The ciliated cells of the efferent ductules projected tufts of cilia into the ductal lumen, while the non-ciliated cells bore short microvilli. The connecting and epididymal ducts were lined by a columnar cell type whose ap ical surface bore uniformly distributed microvilli and a single, centrally situated cilium. The spermatozoa found in all ducts of the epididymis bore a distal cytoplasmic droplet, This observation has implications for the mat urational process in the ostrich spermatozoon in the epididymis. The surfac e features of the ducts, except for a few noteworthy differences, were gene rally similar to those previously described for the male domestic fowl, tur key and duck.