A preliminary study of the effect of total fishmeal replacement with different dietary sources on the gut microbiota of spotted rose snapper juvenile ( Lutjanus guttatus Steindachner, 1869)

Abstract

The aims of this preliminary study were (a) to evaluate the effect of replacing total fishmeal (FM) protein (crude protein, 70.7% CP) with terrestrial animal by-products (porcine meat and poultry by-products; 59.7% CP and 61.6% respectively) and plant meal (soya bean concentrate and corn gluten; CP = 47.3% and 72.7% respectively) on the gut microbiota of Lutjanus guttatus juveniles and (b) to assess the effect of intermittent feeding in transient microbiota. Organisms (106 ± 12 g) were fed a FM, terrestrial animal by-products (PPM) or plant (VEGM)-based diet for ten days; afterwards, they were fed FM diet for ten more days. Samples were analysed using 16S rRNA taxonomic fingerprinting, and function profile analysis was determined by PICRUSt. Serratia and Burkholderia were representative of resident microbiota, while Photobacterium and Vibrio were the predominant genera in transient microbiota. Nor the total FM replacement by PPM and VEGM, nor the intermittent feeding, affected the predominant bacterial populations in the snapper gut microbiota, but significant changes in the amino acid metabolism pathway were observed in PPM group. This research might provide a guideline to define alternative ingredients to fishmeal in order to develop more sustainable diets without negatively affecting the intestinal microbiota composition.