Combined effects of dietary mannan- and fructo-oligosaccharide on growth indices, body composition, intestinal bacterial flora and digestive enzymes activity of regal peacock (Aulonocara stuartgranti)

摘要

A 56-d feeding trial was conducted to investigate the effect of dietary mannan-oligosaccharides (MOS) and fructo-oligosaccharide (FOS) on growth indices, body composition, intestinal bacterial community and digestive enzymes activity of regal peacock. A total of 240 fish were randomly distributed to 15 experimental units (40-L aquariums) of 16 fish each. These replicates were randomly assigned to one of five treatments in a 2 x 2 + 1 factorial arrangement. The treatments were control diet (no MOS and FOS), diet A (2 g kg(-1) MOS + 1.5 g kg(-1) FOS), diet B (2 g kg(-1) MOS + 3 g kg(-1) FOS), diet C (4 g kg(-1) MOS + 1.5 g kg(-1) FOS) or diet D (4 g kg(-1) MOS + 3 g kg(-1) FOS). The results showed that feeding diet C increased specific growth rate and protein efficiency ratio and decreased feed conversion ratio compared with control diet. Higher intestinal trypsin activity and increased Lactobacillus counts were observed in fish fed diets B and C. All diets significantly elevated body protein deposition and intestinal amylase activity compared to the control diet. In conclusion, the diet supplemented with 4 g kg(-1) MOS + 1.5 g kg(-1) FOS was advantageous over other MOS + FOS-supplemented diets, with respect to growth performance and health benefits of regal peacock.