Optimal analysis conditions for sperm motility parameters with a CASA system in a passerine bird, Passer montanus

Background Sperm motility parameters, which can be measured objectively and repeatedly by a computer-assisted sperm analysis (CASA) system, are important indicators of sperm quality. However, the sperm motility parameters assessed by a CASA system can be affected by various factors, including instrument components and settings, sperm preparation or analysis procedures. To date, no standardized protocol is available that would permit to assess sperm kinetic characteristics in passerine birds and this lack precludes any comparison of sperm swimming ability and sperm quality across species.