Assessment of some morphofunctional characteristics of flow-cytometrically sorted and stained boar spermatozoa

The objective of this study was to determine the effect of staining procedure, with or without flow cytometry, on boar sperm membrane integrity (using annexin V/PI staining), mitochondrial activity (using JC-1/SYBR/PI staining) and blastocyst development in vitro. Staining and sorting procedure significantly (p<0.001) reduced the proportion of live sperms with active mitochondria with an increase of late apoptotic/early necrotic cells. However, no significant differences in blastocyst rate among the three types of sperm were observed. Furthermore, no significant differences in the above mentioned parameters were observed between fresh and stored (17°C for 24h) semen, except for an increase of dead sperms, possibly due to staining and sorting after storage. In summary, despite damages induced by sorting procedures, semen sorted as fresh or after storage at 17°C can be used for efficient in vitro production of pig embryos