Fig. 5. The influence of (A) the control treatment or (B) experimental feeding on the rate of ammonia-N excretion in Squalus acanthias of Series 2. Other details as in legend of Fig. 1. There was a significant overall influence of experimental feeding (two-way ANOVA, P x0.05). There were no significant differences between control and experimental treatments at the same time. Values are means ± 1 S.E.M. Data were taken from those dogfish of Series 2 (control N=5, experimental N=4) where there was no struggling or potential for blood loss from fin abrasion.