Age-Related Changes in the Gut Microbiota Composition of Hog Deer (Axis porcinus)

ABSTRACT Comprehensive investigation of gut microbiota composition is important for understanding digestive physiology in mammals. The hog deer (Axis porcinus) is a small mammal at high risk of extinction in the wild. In the present study, we sequenced the V4 region of 16S rRNA gene and compared the gut microbiota composition among three ages of captive hog deer, including one infant (Z1, six months old), three young (Z2, ten months old) and 12 adult (Z3, 4-5 years old). A total of 26 phyla (15, 22 and 25 in Z1, Z2 and Z3) and 310 genera (153, 254 and 304 in Z1, Z2 and Z3) were identified. In Z1, Z2 and Z3, Firmicutes (63.65%, 62.07% and 61.96%) was the predominant phylum, followed by Bacteroidetes (29.08%, 29.62% and 30.02%) and Tenericutes (3.08%, 3.24% and 2.78%). The alpha diversity (Shannon Index and observed species) of Z2 was significantly higher than that of Z3 (P < 0.05). The Shannon Index of Z1 was higher than that of Z2. At the genus level, ChristensenellaceaeR-7group and Ruminiclostridium5 had higher abundance in Z2 compared with Z3, whereas other genera, such as Fibrobacter, LachnospiraceaeAC2044group and Oscillibacter were enriched in Z3. In conclusion, our results reveal significant microbiota composition changes that occur with age in captive hog deer.