Effect of Bradykinin on Murrah buffalo (Bubalus bubalis) semen cryopreservation

Keeping in view the poor freezability of bubaline semen in conventionally used extenders, this study was conducted on three Murrah bulls to improve semen cryopreservation with the incorporation of Bradykinin (0.5, 1.0 and 2.0 ng ml−1) in routinely used egg yolk tris-glycerol (EYTG) extender. Bradykinin (2.0 ng ml−1) had significant (P < 0.05) beneficial effect on live sperm % (81.6 ± 1.8) and hypo osmotic swelling (HOS) % (63.0 ± 1.3) as compared to their respective control values of 73.4 ± 2.1 and 56.3 ± 2.0 at 0 h post freezing. The post-thaw progressive sperm motility in semen samples diluted with EYTG containing 2.0 ng ml−1 Bradykinin (65.5 ± 1.4) was also significantly (P < 0.01) higher than control (60.3 ± 1.9) at 0 h post freezing. Thus incorporation of 2 ng ml−1 Bradykinin in buffalo semen diluted in EYTG extender may be useful in improving the quality of cryopreserved bubaline semen.