Fig. 1. The influence of (A) the control treatment or (B) experimental feeding on arterial pH (pHa; circles) and venous pH (pHv; triangles) in Squalus acanthias of Series 1. The experimental meal was 20 g of flatfish muscle paste in 20 ml of 140 mmol l^–1 NaCl saline per kg dogfish, administered as a bolus down the stomach tube at time 0 h. The control treatment was comparable gastric loading of 40 ml of 140 mmol l^–1 NaCl saline per kg dogfish. Values are means ± 1 S.E.M. (N=5). P represents the pre-feeding measurement (horizontal dotted lines). The overall influence of experimental feeding was significant for both pHa and pHv (two-way ANOVA, P x0.05). Within each treatment, means not sharing the same letter are significantly different (one way ANOVA followed by the LSD test). Asterisks indicate significant differences between control and experimental treatments for the same parameter at the same time.