Influence of a peptidoglycan-enriched diet on growth performance, feed utilization and immune response in striped catfish (Pangasianodon hypophthalmus)

Abstract

Peptidoglycan is considered a type of prebiotic or immunostimulant. However, the utilization of these substances in aquaculture remains limited, with no reported results in striped catfish. The current study aimed to investigate the effects of dietary supplementation of peptidoglycan on the growth performance and immune status of striped catfish. Fish were fed on diets supplemented with various concentrations of peptidoglycan at 0, 2.5, 5, and 10 g/kg of feed, named to PL0, PL2.5, PL5, and PL10 treatments at 4% of fish weight during 4 weeks. Blood samples were collected after 2 and 4 weeks of experiment (T2 and T4) for hematological indices and immune analyses, including lysozyme and peroxidase activities. Results demonstrated that no significant differences were found in fish growth, survival rate, and intestinal indices. The improvements in feed conversion and protein efficiency ratios were observed in PL2.5-fed fish compared to the control. Peroxidase activity in PL10 group was higher than PL0 at T4 while the highest value of lysozyme activity was recorded in fish fed PL10 at T2. In conclusion, dietary supplementation of peptidoglycan at 2.5 g per kg of diet induced a beneficial effect on feed utilization, while positive influences on immune parameters were recorded in fish fed on a diet added peptidoglycan at 10 g/kg feed.

Keywords

• Peroxidase activity
• Lysozyme activity
• Prebiotics
• Immunostimulant