Computer assisted semen analyzers in andrology research and veterinary practice.

The evaluation of sperm cell motility and morphology is an essential parameter in the examination of sperm quality and in the establishment of correlations between sperm quality and fertility. Computer-assisted sperm analysis (CASA) allows an objective assessment of different cell characteristics: motion, velocity, and morphology. The development and problems related to this technology are raised in this review, paying particular attention to the biases and standardization requirements absolutely needed to obtain useful results. Although some interesting results, mainly in humans, have already been obtained, many questions remain, which have to be answered to allow for further development of this technology in veterinary medicine, clinical fertility settings, physiological, and toxicology research activities. The main problem is related to the standardization and optimization of the equipment and procedures. The different CASA instruments have all demonstrated high levels of precision and reliability using different sperm classification methodology. Their availability gives us a great tool to objectively compare sperm motility and morphology and to improve our knowledge and ability to manipulate spermatozoa.