The transportation of fish larvae or juveniles from hatcheries to rearing farms is a crucial process in aquaculture, as most fish farms are located far from hatcheries. Among abiotic parameters, light intensity is an important factor affecting the physiology and biochemistry of teleost fish. To date, most studies on fish transportation have focused on identifying the optimum stocking density, while little is known about the optimum light intensity for transporting hatchery-produced juvenile Crimson snapper (Lutjanus erythropterus). Therefore, this study aimed to evaluate the effects of light intensity on antioxidative stress, digestive enzymes, and ATPases in Lutjanus erythropterus during long-hour transportation. The results of this study revealed that a light intensity between 100 and 500 Lux is recommended for the long-hour transport of L. erythropterus juveniles. Complete darkness increased the concentration of ammonia in the water by about 15 % and induced oxidative stress, whereas high light intensities reduced dissolved oxygen levels (up to 6 %) and pH (up to 6 %), increased water temperature (about 10 %), and caused significant oxidative stress in the fish. It is also worth noting that α-amylase activity increased significantly, while ATPase activity decreased significantly under both complete darkness (α-amylase activity = +40 %; ATPase activity = up to -130 %) and high light intensities (α-amylase activity = +21-52 %; ATPase activity = up to -43 %). The findings of this study can provide a guideline for improving current transportation techniques, thereby minimizing stress on L. erythropterus in a cost effective manner.
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