Fig. 1

Experimental design. Fish were bred and raised as described in the section ‘Zebrafish and diets’. At 40 dpf (juvenile stage) they were fed diet A for 1 week for acclimatisation to dry feed pellets. At 47 dpf, fish were randomly distributed into tanks and fed one of the diets (A, B or C) for 3 weeks. Survival and growth were measured before and during the whole experiment. After 1 week (54 dpf) and after 3 weeks (68 dpf) of feeding the fish. Gut samples were collected for histological, metatranscriptomic and microbiome analyses