Active spermiophagy in the initial part of the proximal efferent duct of the epididymis of normal domestic fowl (Gallus domesticus)

In a study of the absorptive activities of the excurrent ducts of the testi s of birds, six adult cocks of the Ovambo breed of domestic fowl were deepl y anaesthetised and intravascularly perfused with buffered 3 per cent gluta raldehyde. Epididymal tissue was prepared conventionally for electron micro scopy. In favourable sections in three of these birds avid ingestion of spe rmatozoa was revealed in the non-ciliated (Type I) cells of the epithelial lining of the initial part of the proximal efferent duct, at and a little b eyond its junction with the rete testis. No obvious defects were detected i n luminal spermatozoa. The testicular excurrent ducts were neither distende d nor obstructed, and mononuclear cell mobilisation was absent in both the ductal and periductal tissue. The significance of this observation with reg ard to the specific segment of the efferent duct system involved and how ce rtain spermatozoa are identified for elimination from the duct lumen, must await precise studies. (C) 2000 Harcourt Publishers Ltd.