significantly different between low and high DO tanks (P=0.307).
Mean final fish weights in high DO tanks, however, were significantly
higher than in low DO tanks (P=0.004). Effects of fish size were
present in all the responses (Pb0.001). Although absolute feed intake
and growth rates were higher in big fish, these values were smaller in
big fish than in small fish when expressed as percentage of body weight
or per metabolic weight unit. Feed conversion ratios (FCR) of big fish
were higher than small fish. Oxygen significantly affected feed intake
and growth rates (Pb0.005) but had no effect on FCR (P=0.393). In
the same weight class, feed intake and growth rates of fish in high DO
tanks were significantly higher than in low DO tanks (Pb0.05). There
were no interaction effects of fish size and oxygen on any of the
responses (PN0.05), except on the absolute feed intake (Pb0.05).