Abstract:

Objective: To investigate the effect of dietary supplementation of citrate sweet potato starch (CSPS), prepared
using esterification with citric acid, on the growth and intestinal microenvironment of Schizothorax prenanti Tchang.
Methods: Totally 180 fish with an average body weight of (75.47 ± 5.43) g were randomly divided into five groups of 12
fish in each group, with three replicates for each group. Control group was fed a basal diet, and three test groups were fed
a diet supplemented with CSPS at doses of 3.5%, 7%, 14% and 28%, respectively. Sixty days later, all fish were weighed
and dissected, and feed conversion rate, feeding rate and specific growth rate were calculated. After removing the intestine,
the intestinal mucosa height was measured. The intestinal flora was analyzed by PCR-DGGE. Results: Compared with the
control group, final body weight, feeding rate and specific growth rate were significantly increased in 7% and 14% CSPS
groups (P ＜ 0.05). Foregut plica mucosa height was significantly decreased in 14% and 28% CSPS groups (P ＜ 0.05). As
for the midgut, the intestinal flora in 3.5% CSPS group was more similar to in the control group. The foregut and hindgut
intestinal flora revealed an extremely significant difference between the control group and three test groups, despite showing
50.0 ≤ q ＜ 75.0 (moderate similar). Conclusion: The growth of Schizothorax prenanti Tchang is promoted by dietary
supplementation of CSPS at a low dose (7%) but inhibited at a high dose (28%). At the same time, CSPS can affect the
intestinal flora of Schizothorax prenanti Tchang.

Key words: citrate sweet potato starch, Schizothorax prenanti Tchang, food intake rate, plica mucosa height, intestinal flora