We found that DO concentration and diet composition had main effects on intestinal morphology, but those effects were not constant over
time. Those time effects (PWxDxO b 0.05; Table 4) can be seen in LP (Fig. 4)
and GC (Fig. 5) in the proximal intestine and EG (Fig. 6) in the distal intestine. The thickness of LP in the proximal section was similar among
treatments at week 1. However, the thickness of LP increased over time
in fish fed the “Test” diet, and this tendency was greater under hypoxia
at week 4 and week 8 (Fig. 4). The number of GC in the proximal intestine of fish fed the “Test” diet at hypoxia was significantly higher compared to other treatments at week 1.