Semen collection in cats: Techniques and analysis

Sperm collection permits to obtain material for artificial insemination, diagnostic purposes, and use in research. Collections via artificial vagina (AV) and electroejaculation (EE) are the most commonly used in the cat and permit to obtain ejaculates with good quality, but EE seems to be the method of choice. Other methods of semen collection, such as epididymal squeezing or slicing, to achieve material for research have been reported. Semen analysis is essential for the fertility evaluation of male felids, but some of the diagnostic procedures used in other species are difficult or impossible to duplicate, due to the small volume of the cat ejaculate. In practice, sperm motility and viability (using eosin–nigrosin staining), morphology and sperm concentration should be evaluated, even if determination of sperm membrane and acrosomal integrity (using transmission electromicroscopy or fluorescence microscopy), semen chemistries and other parameters can be important for testing both fresh and frozen-thawed sperm. This manuscript reviews the techniques for semen collection and analysis.