The present investigation was designed to study certain morphological characteristics of epididymal washings/plasma during winter and summer season in the bucks. The study was undertaken with the view to fi nd out the effect of different season on

the epididymal physiology of bucks. The epididymis was collected from sixteen apparently healthy bucks, immediately after their slaughter. In the laboratory, separation and washings of caput, corpus and cauda epididymis were carried out separately. The spermatozoa of the cauda epididymis showed higher (P < 0.05) mass motility as compared to corpus epididymis in winter as compared to summer season and caput epididymis in which they were non-motile in both the seasons. The result of present study showed high (P < 0.01) concentration of spermatozoa in different part of epididymis during winter as compared to summer season. During winter season, spermatozoa concentration in the cauda was signifi cantly higher (P < 0.01) as compared to corpus and caput. During summer, live per cent values of spermatozoa were signifi cantly lower (P < 0.01) in caput, corpus and cauda epididymis as compared to winter value of caput, corpus and cauda epididymis. Most of the spermatozoa from the caput epididymis showed the higher cytoplasmic droplet at their neck portion. However, the spermatozoa of the corpus and cauda epididymis revealed a non-signifi cant reduction in the cytoplasmic droplet at the neck portion. All the above parameters indicate that summer stress severely affect epididymal physiology and semen quality of buck.