JKX Oil & Gas (LSE: JKX LN) announced it completed and tested horizontal well R-103 in its Rudenkovskoye field in Ukraine, the first in a series of horizontal wells to develop and further appraise the gas reserves in the deep tight gas Rudenkovskoye reservoirs. The Rudenkovskoye field currently has 21.6 MMboe of probable reserves while JKX’s total proved and probable reserves amounted to 89 MMboe prior to the well testing. JKX plans to review its reserves upon completion of the 2011 Rudenkovskoye drilling campaign.