Effects of fermented feed on growth performance,tissue structure,and intestinal microbiota of Procambarus clarkii in rice-crayfish co-culture systems

HAN Guangming; WU Leiming; QIN Baoli; KOU Xiangming; ZHANG Jiahong; WANG Shouhong; YE Xiaomei; XU Hongqin

doi:10.13557/j.cnki.issn1002-2813.2025.14.011

Abstract：The experiment aimed to investigate the effects of fermented feed on the growth performance,tissue structure,and intestinal microbiota of Procambarus clarkii in rice-crayfish co-culture sytems.A total of 800 healthy Procambarus clarkii of comparable size were randomly allocated to two groups,four replicates in each group and 100 Procambarus clarkii in each replicate.The control group was fed with commercial pellet feed,while the experimental group was fed with bio-fermented feed.The pre-test period was seven days and the formal test period was 60 days.The results showed that the final weight,weight gain rate,and specific growth rate of Procambarus clarkii in the experimental group were significantly higher than those in the control group(P＜0.05),and the feed coefficient was significantly lower than that in the control group(P＜0.05).The final weight,average final body length,fat fullness degree,and chelate ratio of the female shrimps in the experimental group were significantly higher than those in the control group(P＜0.05),and the abdominal meat content rate was significantly lower than that in the control group(P＜0.05).The abdominal meat content rate of male shrimp in the experimental group was significantly lower than that in the control group(P＜0.05).In the experimental group,the lumen structure of the hepatic tubules of the hepatopancreas presented an irregular polygonal star shape,with an increase in the number of enlarged secretory vacuoles and fibroblasts,and the number of microvilli on the intestinal folds was increased.There was no significant difference in the diversity index of intestinal flora between the two groups(P＞0.05).The dominant bacterial phyla in the intestinal tract were Tenericutes,Firmicutes,Proteobacteria,and Bacteroidetes of Procambarus clarkii.The dominant bacterial genera were Anaerorhabdus,Pseudomonas,Dysgonomonas,and Bacteroides.Compared with the control group,the relative abundances of the Tenericutes and Firmicutes in the intestinal tract of shrimp in the experimental group increased,while the relative abundances of the Proteobacteria and Bacteroides decreased.The relative abundances of Anaerorhabdus and Bacteroides in the experimental group increased,while the relative abundances of Pseudomonas and Dysgonomonas decreased.The study indicates that fermented feed can enhances growth,reduces feed coefficient,improves the composition of intestinal microbiota,and alter the structure of intestinal and hepatopancreatic tissues in Procambarus clarkii in rice-crayfish co-culture systems.