Multifactors have been reported to affect the gut microbiome,including genotype,age,diet,and nutrition.However,few reports have investigated the relative capacity of different factors to shape the gut micro-biome in a single study.Our design used a genetic vitamin A-deficient mouse model,the Rbp4-/-mouse,feeding with the low vitamin A diets at different ages of initiation(4 or 7 weeks)for 28 days.Fecal samples were collected for bacterial profiling at seven time points after diet controlling.With Rbp4 depletion,Akkermansia decreased and Bacteroides increased,whereas Desulfovibrio,Barnesiella,Clostridium_XIVa,and Lactobacillus fluctuated.The bacterial community swiftly adjusted with the vitamin A-deficient diet administration and gradually changed(e.g.,decrease of Barnesiella and increase of Desulfovibrio).Age exerted a relatively weaker but long-last influence.At an earlier age to feed a vitamin A-deficient diet,a higher microbial dysbiosis index will be valued.Of note,the shaping effects of diet and age on the bacterial community varied with the difference of genotype,which might indicate a greater role of genotype than diet and age in shaping the gut microbiome.