Cryopreservation of in situ cool stored buffalo (Bubalus bubalis) epididymal sperm

The objectives of this study were to investigate the effects of testis-epididymis cool storage on viability and progressive motility of buffalo epididymal sperm (EP) and to compare the influences of two basic semen extenders on post thaw EP viability and progressive motility. Abattoir collected buffalo testicles were allotted to three storage times (0 h: n = 10; 24 h: n = 10 and 48 h: n = 12). Following storage, isolated sperm were subjected to cryopreservation with two different cryoprotective media: whole cow milk-7%glycerol (MG) or egg yolk-tris-citrate-7%glycerol (EYG). Pre freeze and post thaw sperm progressive motility and viability were evaluated. Results indicated that viability and progressive motility of sperm decreased after 24 h cool storage of the epididymis (P<0.05). There was no difference between 24 and 48 h of storage on sperm viability (P>0.05), but progressive motility decreased across storage times (24 h versus  48 h: P<0.05). Cryopreservation severely influenced viability and progressive motility of EP (P<0.05). Milk-7%glycerol protected viability and progressive motility of EP against cold shock more efficiently than EYG (P<0.05). The results of this study demonstrate that it is possible to preserve buffalo EP within the epididymis at 4°C short term, but that it has poor freezability upon recovery by basic semen freezing protocols.