Splenectomy impairs aerobic swim performance in trout

Critical swim speed (U(crit)) measurements show that trout (Oncorhynchus mykiss) with an intact spleen perform aerobic exercise better than those without (control: U(crit) = 2.19 body lengths/s; splenectomized: U(crit) = 1.84 body lengths/s). Their better performance is correlated with higher blood haemoglobin concentration at exhaustion (control: 9.92 g/dL; spenectomized: 7.96 g/dL), derived from release of red cells from the spleen.