Freezability of water buffalo spermatozoa is improved with the addition of catalase in cryodiluent.

BACKGROUND: Catalase enzyme is usually distributed in mammalian seminal plasma, where it decomposes hydrogen peroxide into water and oxygen and enhances sperm survivability.

OBJECTIVE: To evaluate the effect of catalase (0, 100, 200 or 300 IU/ml) added in tris-citric acid (TCA) based extender on motion characteristics, viability and DNA integrity of bubaline spermatozoa at post dilution (PD) and post thawing (PT) stages of cryopreservation.

MATERIALS AND METHODS: Collection of semen was done in four Nili-Ravi bulls with an artificial vagina (42 degree C). Qualified semen samples from each bull were further subdivided into four aliquots for dilution with the experimental TCA extender containing either 0.0 (T1), 100 IU (T2), 200 IU (T3) or 300 IU (T4) catalase (activity12660 U/mg).

RESULTS: At PT, mean computer progressive motility, average path velocity, straight line velocity, curvilinear velocity, visual motility and DNA integrity were higher (P < 0.05) in catalase fortified treatment groups as compared with control. Regarding plasma membrane integrity and supra-vital plasma membrane integrity, at PT the mean values were higher (P < 0.05) in T4 as compared with control. At PD and PT, mean acrosomal integrity of buffalo bull spermatozoa was higher (P < 0.05) in T4 group as compared with control.

CONCLUSION: Addition of catalase at a concentration of 300IU/ml in TCA cryodiluent improved the freezability of water buffalo spermatozoa.