Nanoparticle-encapsulated hepcidin as a dietary strategy to improve growth, biochemical status, and immune responses in common carp (Cyprinus carpio) pre- and post-Aeromonas hydrophila challenge.

Various antimicrobial peptides are small peptides with potential for controlling pathogenic microorganisms. Nanoencapsulation of antimicrobial peptides is a strategy to limit some challenges, such as low stability, and improve the efficacy of these antimicrobial drugs. This study was designed to assess the efficacy of encapsulated hepcidin within nano-carboxymethyl chitosan and nano-β-cyclodextrin compared to natural hepcidin on the growth, immunity, and biochemical responses in common carp (Cyprinus carpio) following the challenge with Aeromonas hydrophila. Fish (5.05 ± 0.22 g) were acclimatized and then divided into four experimental groups supplemented with a control diet (CTR), a diet with natural hepcidin (Hep), a diet with hepcidin within nano-carboxymethyl chitosan (CMCS-Hep), and a diet with hepcidin within nano-β-cyclodextrin (βCD-Hep) for 8 weeks and then challenged with pathogenic A. hydrophila. Results showed that fish fed the CMCS-Hep diet demonstrated significant differences in final weight, liver-related enzyme activities, stress and immune indices compared to the CTR and Hep groups. In conclusion, the present study showed that common carp might appear to benefit from encapsulated hepcidin within nano-carboxymethyl chitosan in terms of growth, biochemical and immunological traits.