Fig. 3. NADH-dependent ferrireductase activity in gill (A), intestine (B) and liver (C) of rainbow trout fed a casein-based diet containing low (filled square), normal (filled diamond) and high (filled circle) levels of Fe for 8 weeks. Values are means ± S.E.M. (N=6). Other details and statistics as in Fig. 1. No differences were observed between treatments in gill tissue. No differences were observed between initial fish and those on the normal Fe diet at week 2. Insets are log[Fe] in tissue correlated with ferrireductase activity for intestine (B inset, y=-16.63x+38.10 for low- and high-Fe diets, N=18) and liver (C inset, y=105.03x-1.24, for normal and high-Fe diets, N=18). Note, ferrireductase activity is normalised per minute (nmol mg^-1 min^-1).