Cryoprotective Effects of Vitamin B₁₂ Supplementation on Bovine Semen Quality

• Published in: Reproduction in domestic animals 2011-02, Vol.46 (1), p.66-73
• Main Authors: Hu, J.H, Tian, W.Q, Zhao, X.L, Zan, L.S, Xin, Y.P, Li, Q.W
• Format: Article
• Language: English
• Subjects: Acrosome - ultrastructure; Animal reproduction; Animals; Antioxidants; Antioxidants - metabolism; Biological and medical sciences; Body fluids; Catalase - metabolism; Cattle; Cell Membrane - ultrastructure; Cryopreservation - methods; Cryopreservation - veterinary; Cryoprotective Agents - administration & dosage; Fundamental and applied biological sciences. Psychology; Glutathione Peroxidase - metabolism; Hot Temperature; Male; Males; Mammalian reproduction. General aspects; Oxidative Stress - drug effects; Quality; Semen - physiology; Semen Preservation - methods; Semen Preservation - veterinary; Sperm Motility; Spermatozoa - physiology; Spermatozoa - ultrastructure; Superoxide Dismutase - metabolism; Vertebrates: reproduction; Vitamin B; Vitamin B 12 - administration & dosage
• ISSN: 0936-6768; 1439-0531
• DOI: 10.1111/j.1439-0531.2009.01575.x

The present study aimed to investigate the effects of vitamin B₁₂ supplementation on standard bovine semen quality parameters and anti-oxidative enzyme activities. Vitamin B₁₂ was supplemented at concentrations of 1.25, 2.5, 3.75 and 5.0 mg/ml to bovine semen cryoprotective medium. The results indicated that the motility and straight line velocity, curvilinear velocity, mean coefficient, velocity of the average path values of sperm supplemented with 2.50 mg/ml vitamin B₁₂ were significantly higher than that of other groups (p < 0.05). No significant difference was observed for linearity index, lateral head displacement values and the percentage of grade A spermatozoa between the extenders containing 2.50 and 3.75 mg/ml vitamin B₁₂ (p > 0.05). The percentages of acrosome-intact and plasma membrane-intact spermatozoa were significantly improved (p < 0.05) by supplementing with 2.50 mg/ml vitamin B₁₂. The results of biochemical assay revealed that vitamin B₁₂ supplementation did not cause significant changes in superoxide dismutase levels compared with control (p > 0.05). However, the catalase levels were higher in the treatment supplemented with vitamin B₁₂ at 2.50 mg/ml, when compared with other groups (p < 0.05). The extender supplemented with vitamin B₁₂ significantly decreased glutathione peroxidase activity compared with the control (p < 0.05). The supplementation of 3.75 mg/ml vitamin B₁₂ caused the highest value of glutathione reductase activity, compared with other groups (p < 0.05). In conclusion, the extender supplemented with vitamin B₁₂ could reduce the oxidative stress provoked by freezing-thawing and improve bovine semen quality. Further studies are required to obtain more concrete results on the determination of lipid peroxidation and antioxidant capacities of vitamin B₁₂ in cryopreserved bovine semen.