Abstract
Cryo-banked semen is playing vital role in the advancement of modern dairy production. Success in semen cryopreservation is still debatable because several factors are accountable for it. Generally, the process of freezing-thawing is believed to cause 50% decline in sperm quality. Cholesterol enrichment of sperm plasma membrane using cholesterol-loaded cyclodextrin (CLC) has been proved beneficial for sperm cryo-survival of several mammalian species. This study was aimed to minimize the decline in sperm quality parameters of buffalo during the cryopreservation process through pre-freezing treatment with CLC. Semen was collected from three Nili-Ravi buffaloes, pooled. After initial evaluation the sample was divided into two aliquots (one aliquot as control and other as CLC treated with CLC). Both aliquots were diluted in Tris citric acid buffer with second aliquot additionally treated with 2mg CLC/120x106 sperm. After 15 min incubation, both samples were diluted in Tris based diluents and frozen with standard procedure. Decline of sperm motility, viability, plasma membrane integrity (PMI), normal apical ridge (NAR) from fresh to post-thaw were assessed. Significant differences (P < 0.05) were found in decline of all sperm quality parameters between control (C) and CLC treated (T) samples. The decline from fresh to post-thaw in motility (43.34±3.33 vs. 25.97± 3.26), viability (31.90±2.20 vs. 19.64±2.36), PMI (32.01±2.46 vs. 17.26±1.19) and NAR (35.36±4.17 vs. 26.90±1.12) were found higher (P < 0.05) between C vs. T, respectively. It is concluded that cholesterol addition to sperm membrane can reduce the deleterious effect of cryopreservation in buffalo bull sperm.
