The purpose of this study was to assess the effects of three different extenders as Modena,

Beltsville Thawing Solution (BTS), and Kiev on the quality of boar semen preserved in some

boar breeds in Vietnam. Semen samples of 6 Yorkshire boars were collected then diluted in three

extenders and stored at 17oC for up to 144h. The semen parameter as viability, motility, and

extender quality as pH, and bacteria status were assessed and compared after 72, 120, and 144h of

preservation. Results showed that Modena extended boar semen had better motility, and survival

rate than BTS and Kiev extended boar semen after 144h preservation. The value of pH was stable

and acceptable during the experiment period, Modena was a higher value of pH than BTS and

Kiev. Moreover, bacteria status was higher in semen preservation in Kiev than in Modena and BTS.

Thus, the Modena had a more beneficial effect on stored boar semen during 120h preservation, and

BTS and Kiev had the ability to preserve boar semen within 72h in the current study.