Indian Journal of Animal Research

The objective of present study was to investigate the effects of two different levels of dissolved oxygen (DO) i.e. 4 and 8 ppm in the extenders on physico-morphological attributes and functional membrane integrity of crossbred bull spermatozoa following cryopreservation. Only those ejaculates that had a mass activity of ≤ 3+ and individual progressive motility of ≤ 70% were utilized. Each of the ejaculates were divided and extended to have 80×10⁶ spermatozoa/mL of extender in three groups i.e. Group I (control), Group II (4 ppm) and Group III (8 ppm). Progressive motility (%) was higher (p<0.05) in Group II and III as compared to Group I at both pre-freeze and post-thaw stage. Per cent live sperm and HOST reactive sperm were higher (p<0.05) in Group II and in Group II and III as compared to Group I at pre-freeze and post-thaw stage, respectively. Sperm abnormality (%) was lower (p<0.05) in Group II at post-thaw stage. Per cent acrosome intact sperm did not differ (p>0.05) among the groups at pre-freeze stage, but, were higher (p<0.05) in Group II and III as compared to Group I at post-thaw stage. In conclusion, cryopreservation of semen having DO level of 4 ppm in semen extender yielded better resultsfollowed by 8 ppm in terms of semen qualityparameters and functional membraneintegrity ofcrossbred bull spermatozoa.