Assessment of boar sperm function in relation to freezing and storage

The functions necessary for normal fertilization to occur in vivo or in vitro are examined and a rational approach to identifying the main features of a fertilizing spermatozoon are developed. It is concluded that methods for testing the quality of spermatozoa must probe the dynamic changes experienced by the spermatozoa during capacitation or under stressful incubation conditions. Recent developments in the multivariate analysis of sperm motility data are used to illustrate the success that can be achieved by this approach. Ideally, changes in sperm motility characteristics should be correlated with an assessment of capacitation status. However, until the capacitation status of any individual cell can be clearly defined this will remain problematic.