S-type rotifers were reared in 2000 l tanks following the same procedureas for L-type rotifers.Starting density was 1000 rotifers per ml. The feeding regime was adjusted according to the growth of the rotifers and was 0.5, 0.4, 0.25 and 0.2 g·million−1 of rotifers on days 0, 1, 2, and 3 respectively