Under oxidative stress condition, the protective effects of dietary
chlorogenic acid (CGA) supplementation on liver
antioxidant capacity, intestinal
inflammation and barrier function, muscle development and skin coloration in channel catfish Ictalurus punctatus were explored in the current study. With that purpose, I. punctatus were fed five experimental diets containing 2% fresh
fish oil (FFO, 9.2 meqO2/kg) or 2% oxidized
fish oil (OFO, 897.4 meqO2/kg) without or with CGA supplementation (0.02%, 0.04% and 0.08%) for 8 weeks. Upon comparative analysis, the oxidized
fish oil consumption significantly lowered
weight gain rate, decreased intestinal villi length and muscular thickness values and the
tight junction proteins mRNA abundance, augmented the intestinal proinflammatory factors, attenuated hepatic
antioxidant enzymes activities and related genes
mRNA expression levels, influenced the
myogenic regulatory factors expression profile and impacted the myocyte density, myocyte area values as well as the skin pigments contents compared to the FFO treatment. Collectively, long-term feeding of the oxidized
fish oil diet suppressed the growth performance, destroyed intestinal structural integrity, caused intestinal
inflammation and hepatic oxidative stress, impacted the skeletal development and skin color of I. punctatus. Whereas CGA supplementation in oxidized
fish oil diets partially counteracted the negative effects of the oxidized
fish oil on I. punctatus in terms of increasing the growth performance, improving the intestinal mucosal structure, alleviating hepatic oxidative stress and intestinal
inflammation, recompiling the
myogenic regulatory factors expression and improving skin color. In conclusion, CGA has great potential to be an aquatic feed additive.