Effects of Adding Permeating and Non-Permeating Cryoprotectants on the Quality and Fertility of Buffalo Semen

Abstract

It is known that buffalo spermatozoa are very susceptible to hazards during freezing and thawing with considerable damage to motility apparatus, plasma membrane and acrosomal cap, as well as leakage of intracellular enzymes. Reduction of about 50% in sperm motility, viability and membrane integrity are major problems occurring during cryopreservation, caused by sub lethal damage in sperm membrane during freezing and thawing processes.Recent studies have been conducted to modify semen extenders for protecting buffalo sperm during freezing- thawing process.The present study was conducted to determine (1) the effect of various concentration of soybean lecithin (SL) as an alternative for egg yolk (EY) in buffalo bull semen extender on pre-freeze and post- thaw sperm quality characteristics, (2) the effectiveness of type and concentration of different non-permeable [egg yolk (EY), soybean lecithin (SL) and cholesterol-loaded cyclodextrins (CLC)], permeable [di-methyl sulphoxide (DMSO) and ethylene glycol (EG)] and antioxidative [butylatedhydroxytoluene (BHT)] cryoprotectants on the functional sperm quality in buffalo bulls pre- and post-freezing extended with egg yolk (TCFYG) and lecithin (TCFGL) - based extenders, and (3) The influence of different cryoprotectants on fertility rate of buffalo cows inseminated with frozen-thawed buffalo bull semen extended in TCFYG (control) and TCFGL extenders.Semen ejaculates were collected from 4 buffalo bulls using an artificial vagina. The ejaculates