EMERGING MARKETS-S.African rand slips ahead of GDP; rate hike bets buoy Russian rouble – Reuters
* S.African economy likely slowed in Q1 – Reuters poll
* 50 bps interest rate hike in Russia expected on Friday – ING
* Mexican peso pares back gains made on midterm election results
* MSCI EM stocks index falls for fifth straight session
June 8 (Reuters)…