Problem statement: Boar sperm cells are sensitive to the freezing process, whichcompromises viability of frozen-thawed sperm. In a constant search for minimizing or suppressingsperm cell damage caused by the temperature and osmolarity changes during the freezing process,crioprotective and antioxidant substances have been added to the freezing media, such as coconutwater, in order to increase the viability of frozen-thawed swine semen. The addition of any substanceto the freezing diluent, directly affects osmolarity of the media, which can have positive or negativeeffects over the sperm cell. Approach: There are no published studies currently that indicate the effectof adding coconut water over the osmolarity of freezing media and their effect over viability of spermcells, therefore, the objective of the present study was to evaluate the effect of coconut water baseddiluents osmolarity over the Motility (Mot), Acrosome Integrity (AI), Membrane Integrity (MI) andMitochondrial Activity (MA) of thawed boar sperm cells. The treatments used were control T1 (LEYwith bidistilled water + LEYGO) with an osmolarity range of 296-368 mOsmol Kg-1, T2 (LEY anddeionized coconut water + LEYGO) between 381 and 480 mOsmol Kg-1 and T3 (LEY and in naturacoconut water + LEYGO) between 519 and 1041 mOsmol Kg-1. The Westendorf modified methodwas the freezing method used. The obtained data were statistically analyzed by GLM, using the SASsoftware (SAS, 2000). Results: A significant difference was observed on T2 compared to T1 regardingMot 41.9 Vs 36.9% and MI 58.0 Vs 50.2. T3 had a detrimental effect on all studied variables.Conclusion: Under our study conditions, the osmolarity range of T2, due to the non ionic solutescontent, contributed to improve the viability of frozen-thawed sperm cells.
