EFFECT OF L-CYSTEINE ON POST THAW QUALITY OF NILI RAVI BUFFALO (BUBALUS BUBALIS) BULL SPERMATOZOA CRYOPRESERVED IN TRIS CITRIC ACID EXTENDER - F. Wadood; M. Aleem; A. Ijaz; N. Ahmad; M. S. Yousaf; D. H. Mughal; A. Javid 8and S. A. Mahmood (Journal of Animal and Plant Sciences, 2015)