Abstract:In this study, the influence of three intestinal potential probiotics, Bacillus firmus, Photobacterium damsela, and Vibrio alginolyticus supplementation was investigated on digestive enzyme activities (pepsin, lipase and amylase) and intestinal bacteria of Litopenaeus vannamei. Probiotic B. firmus (live, 1.0×108CFU/g) tandem 1% P. damsela (inactivated), probiotic B. firmus (live, 1.0×108CFU/g) only, or probiotic B. firmus (live, 1.0×108CFU/g) tandem 1% V. alginolyticus (inactivated) was added to the basic feed for the treatments. No probiotic was supplemented to the control. Mean digestive enzyme activities of all probiotic treatments were significantly different (P<0.05) from that of the control. Besides, total and dominant bacterial counts in probiotic-supplemented groups were different from that in the control. The B. firmus + P. damsela treatment demonstrated the highest amylase activity; the B. firmus + V. alginolyticus treatment demonstrated the highest lipase and pepsin activity; the B. firmus only treatment demonstrated the greatest numbers of total and dominant bacterial counts. It was found that supplementation of probiotics to the basic feed could significantly increased digestive enzyme activities and improve the shrimp's intestinal flora. The multispecies probiotics showed better effect.
