Effects of chito-oligosaccharides supplementation on growth performance, intestinal cytokine expression, autochthonous gut bacteria and disease resistance in hybrid tilapia Oreochromis niloticus ♀ × Oreochromis aureus ♂.

摘要: We investigated the effects of incorporating chitinase (ChiB565)-hydrolyzed shrimp shell chitin into diet hybrid tilapia (Oreochromis niloticus ♀ × Oreochromis aureus ♂) with regard to production, intestinal immune status and autochthonous gut bacteria, protection against bacterial pathogen Aeromonas hydrophila. Five experimental diets were formulated by supplementing basal hydrolyzed (0.0%, T1 control; 0.8%, T3; 1.6%, T4; or 2.4%, T5) 0.1% commercial chitosan-oligosaccharides as recommendation dose (T2, positive control). After a 35-day feeding trial, we found no significant difference in weight gain, feed conversion ratio survival rate among all treatment groups. However, levels mRNAs encoding pro-inflammatory protein tumor necrosis factor-α stress-response heat shock 70 much lower groups T2, T3, T4 T5 (p < 0.001). The transforming growth factor-β higher T2 (p < 0.001 p < 0.0001, respectively). In addition, group T3 0.8% 1.6% supplementation respectively changed marginally their bacteria (0.60 < Cs < 0.80). When challenged A. hydrophila, mortality fed chito-oligosaccharides was than control, especially (p < 0.05). These results indicate that dietary intake can improve health, resistance infection even efficiency receiving manufacturer recommended chitosan-oligosaccharides.