A review on goat sperm cryopreservation

The ability to cryopreserve spermatozoa from all of the domestic species is challenging. Even though all of the cells must endure similar physical stresses associated with the cryopreservation processes, sperm from the different species are very different in size, shape and lipid composition, all of which affect cryosurvival. Thus, when a cryopreservation protocol has been optimized for sperm of one species, it may not be ideal for sperm of other species. Bovine and caprine sperm-freezing diluents, for example, contain similar ingredients, but interactions between goat seminal plasma and egg yolk are deleterious to the sperm, a situation not observed with bovine seminal plasma and egg yolk. Therefore, a thorough understanding of the specifics of sperm freezing from a particular species will improve the cryosurvival of sperm from that species. This review updates information relating to the cryopreservation of goat semen, with emphasis on the peculiarities specific to the species. The topics discussed include the effects of goat seminal plasma during cryopreservation, sperm dilution and concentration, freezing and thawing methodologies, the components of cryopreservation diluents, and traditional and recently investigated cryoprotectants. In addition, suggestions for creating a standardized freezing protocol for goat semen are also presented.