Objective To investigate the effects and timeliness of spleen deficiency on intestinal microorganisms using 16 S rDNA sequencing technology of intestinal microorganisms. Methods A total of 48 rats were randomly divided into a control group and a spleen-deficiency group

and each group was divided into 3 subgroups of time points 2

10

and 16 weeks. Each group had 8 rats at each time point

half male and half female. The spleen-deficiency group established a model of spleen-deficiency by irregular diet and strenuous swimming. Body weights of male and female rats were measured at 0

2

10

and 16 weeks

and urine D-xylose excretion rate and serum amylase activity were detected at 2

10

and 16 weeks. Intestinal microbiota Beta diversity analysis and Alpha diversity analysis were used to compare changes in intestinal microbial abundance and species composition at different time points in the control group and the spleen deficiency group. Results Compared with the control group at the same time

the weight of female and male rats in the spleen-deficiency group was significantly reduced at 2

10

and 16 weeks（P<0.05 or P<0.01）; the urine D-xylose excretion rate of rats in the spleen-deficiency group was decreased significantly at 2

10

and 16 weeks

and serum amylase also decreased at 2 and 10 weeks（P<0.05 or P<0.01）. 16 S rDNA sequencing results showed that in analysis of intestinal flora Beta diversity

there were 8 species in the control group with linear discriminant analysis（LDA）>2 and with significantly higher abundance in the group. The number of species in the spleen deficiency group was 14 at 2 weeks

27 at 10 weeks and 8 at 16 weeks. Alpha diversity analysis results showed that compared with the control group

the intestinal microbial ACE and Observed index of rats in the spleen-deficiency group showed an upward trend at 2 and 10 weeks

and a downward trend at 16 weeks

but there was no statistically significant difference（P>0.05）. The ACE and Observed index of rats in the spleen-deficiency group at 16 weeks were significantly lower than that of the group at 2 and 10 weeks（P<0.05）. Compared with the control group

the level of α-proteobacteria in the intestinal flora of the spleen-deficiency group increased significantly at 2 weeks（P<0.01）. Compared with the spleen deficiency group at 2 weeks

the levels of α-proteobacteria and actinomycetes decreased at 10 and 16 weeks in the spleen deficiency group（P<0.05 or P<0.01）

and there was no statistically significant difference in verruca microflora at each time point（P>0.05）. Conclusion The weight loss and metabolic function of rats under spleen deficiency conditions may be related to the changes in the abundance of intestinal flora and the number of species

and the state of spleen deficiency may gradually decrease with time.