Abstract: | The effects of long-term (14 months) unilateral vasoligation on the tests and their excurrent ducts of the domestic fowl were studied histologically and ultrastructurally. Severe testicular degeneration and epididymal atrophy were observed in the ipsilateral organs while the contralateral control organs were normal. Massive macrophage activity was observed in the epididymal regions and to a lesser extent in some severely degenerated seminiferous tubules. Several granulomata occurred in the epididymal regions and the ducti deferentes, and most were resorbed or were undergoing resorption at the time of examination. |