摘要：This study aimed to investigate the effectiveness of synbiotic (prebiotic alginate and probiotic bacteria Micrococcus
spp) on the immune responses, growth performance, and bacterial resistance of freshwater crayfish. The
experimental diets were formulated in three levels of synbiotic: the probiotic bacteria Micrococcus spp+100 mg/L
alginate (Syn100), Micrococcus spp+200 mg/L alginate (Syn200), Micrococcus spp+300 mg/L alginate (Syn300),
each level was mixed with tested feed. The basal diet (without synbiotics) served as the control diet. During 40 days
of rearing, immune responses observations were conducted every 10 days, while the crayfish weight was recorded
on day 40. Furthermore, the challenge test was performed against the pathogenic bacteria of Aeromonas hydrophila
and reared for a week. The result showed that synbiotics treatment of Syn300 and Syn200 could improve the
immune response and increased the growth rate (P<0.05). Both were also higher than that of the Syn100 treatment,
while the lowest was the control. The highest resistance to A. hydrophila pathogenic bacteria by demonstrating a
higher survival rate was Syn300 and followed by Syn200 (70.00 ± 0% and 73.33 ± 5.77%, respectively), compared
to Syn100 (56.67 ± 3.33%) and the control (33.33 ± 3.33%). The synbiotic Micrococcus spp. combined with
alginate potentially induced immune responses, increased growth performance, and improved bacterial pathogens
resistance, making it an ideal synbiotic to be developed.
关键词：synbiotic; prebiotic; probiotic; Sargassum sp.; alginate; brown algae
其他关键词：synbiotic; prebiotic; probiotic; Sargassum sp.; alginate; brown algae
