# Uncovering the Effects of Different Formulae of Milk Powders on the Fecal Microorganisms and Metabolites of Bengal Tiger (Panthera tigris spp. tigris) Cubs

## TL;DR

This study compares the effects of goat and dog milk replacers on the gut microbes and metabolites of Bengal tiger cubs, finding that diet influences their gut health and metabolism.

## Contribution

The study provides empirical evidence that milk formula composition affects gut microbiota and metabolism in Bengal tiger cubs.

## Key findings

- Dog milk replacer increased probiotic bacteria and balanced the gut microbiota in tiger cubs.
- Different milk formulae altered fecal metabolites and metabolic pathways, including amino acid and lipid metabolism.
- The dog milk replacer group showed significant up- and down-regulation of specific metabolites.

## Abstract

Captive Bengal tiger cubs in zoos are frequently abandoned by their mothers, posing a significant threat to the development and sustainable preservation of the Bengal tiger population. To optimize diet and improve the health and survival of Bengal tiger cubs, we performed microbiome and metabolomics analyses on fecal samples from Bengal tiger cubs fed goat and dog milk replacer formulae. This study confirmed that milk formula composition influences the gut microbiota and metabolism of Bengal tiger cubs. These findings may provide new insights into how different milk formulae and dietary strategies affect the regulation of the gut microbiota and overall health of Bengal tiger cubs.

In order to optimize diets for Bengal tiger cubs and improve their health condition and survival rates, we conducted microbiota and metabolomics analyses on fecal samples from Bengal tiger cubs fed goat and dog milk replacer formulae. The results showed that there were significant differences in fecal microorganisms and metabolites between the two groups. At the phylum level, the major components of the microbial composition in the feces of cubs were Firmicutes, Actinobacteriota, Proteobacteria, Bacteroidota and Fusobacteriota. In addition, the abundance of gut microbiota varied significantly between the two groups of tiger cubs. The fecal microbiota of the tiger cubs fed dog milk replacer powder exhibited an increase in probiotic bacteria (Anaerostipes and Clostridium_scindens) (p < 0.05), and the microbial community tended to be more balanced. Metabolomics data further elucidated that feeding different milk formulae significantly affected the fecal metabolites and metabolic pathways in the Bengal tiger cubs. In the dog milk replacer powder group, 76 metabolites were up-regulated (p < 0.05), and 278 metabolites were down-regulated (p < 0.05), particularly affecting the metabolism of vitamin D3, vitamin B5, isoleucine, valine, phenylalanine and oleic acid. At the same time, 19 metabolic pathways were affected (p < 0.05), including the amino acid metabolism, lipid metabolism and nucleotide metabolism pathways. In conclusion, this study confirms that milk formula composition affects the gut microbiota and metabolism of Bengal tiger cubs. These findings may provide new insights into how different milk powder formulae and dietary strategies influence the regulation of gut microbiota and overall health in Bengal tiger cubs.