Background: Intestinal microbiota communities can reflect the digestion and metabolism of the host, as well as the appearance of the host. In China, there are various excellent horse and pony breeds with rich diversity in wither height. However, little is known about the community structure of the intestinal microbiota in horses, let alone the profound effects it causes.
Results: Here in, we generated 16S rRNA sequences of intestinal microorganisms from 118 Chinese horses including Guanzhong horse, Debao pony, and Ningqiang pony. We found that the intestinal microbiota of horses is full of diversity, and Firmicutes, Bacteroidetes, and Spirochaetes, which is consistent with the special structure of the horse digestive tract. Interestingly, the abundance of Firmicutes and Bacteroidetes at the phylum level, showed a strong correlation with horse height, with R values of 0.82 and -0.86 respectively. Moreover, at the genus level, Coprococcus, Streptococcus, Treponema, and Prevotella demonstrated higher significance in terms of height, the prediction of PICRUSt2 function and multiple analyses of the metabolic pathways, and additionally, the metabolic pathways of energy intake and utilization were significantly enriched in horses relative to ponies (P<0.01). Notably, flora colonization in mouse littermates contributed to their broad development compared to the control group.
Conclusions: Compared with ponies, the intestinal microbiota enabled better cellulose decomposition and energy uptake in horses; Thus horses could get more energy from food to meet their higher demand for larger body development than ponies. Therefore, our study helps to understand the gut microbiota patterns across equine breeds, which has the potential to advance approaches aimed at personalized microbial modifications in horse breeding.