Cryopreservation induces capacitation-like changes of the swamp buffalo spermatozoa

Abstract

A total of forty ejaculates were collected from eight buffalo bulls by artificial vagina method. Each ejaculate was splitted into two parts, one part was used for in vitro capacitation by TALP medium, and the rest was frozen in Tris-egg yolkcitrate-glycerol extender. The results revealed that the live acrosome reacted and total acrosome reacted frozen thawed spermatozoa differed significantly (P<0.01) from in vitro capacitated spermatozoa at different hours of incubation. The incidence of hyperactivated motility, total HOSTreacted spermatozoa, sperm membrane protein and cholesterol level of frozen thawed spermatozoa also differed significantly (P<0.01) from in vitro capacitated spermatozoa during different hours of incubation except at 0 h for hyperactivated motility, 6 h for total HOST-reacted spermatozoa, 1 h for sperm membrane protein level and at 2 h for cholesterol level. The study suggests that cryopreservation induces capacitation-like changes of the swamp buffalo spermatozoa in respect of acrosomal status, plasma membrane integrity, membrane protein and cholesterol levels.