Kolkata: What can the bacteria living inside a tiger’s gut tell us about its health and life in the wild? Quite a lot, suggests a new study on Bengal tigers, which has found that wild tigers have a richer, more diverse community of gut microbes than those living in captivity.The research by Zoological Survey of India scientists highlights the role of habitat in shaping tiger gut microbiome. “The findings could have implications for tiger conservation beyond conventional monitoring of health, genetics and behaviour. Gut microbiome assessments could eventually become an additional tool in captive breeding, animal exchanges between zoos and reintroduction programmes,” said the report, published recently in Molecular Biology Reports.“A tiger’s gut contains a community of microorganisms that helps process food and supports metabolism and immune function. Studying these bacteria can provide clues about the animal’s diet, environmental exposure and digestive health. We can examine this community through DNA recovered from fresh droppings. Comparing wild and captive animals helps us understand how their living conditions are reflected in their bodies. However, this alone cannot establish whether a tiger is healthy or sick,” said ZSI senior scientist Mukesh Thakur, who led the study ‘Exploring Sex- and Captivity-Associated Gut Microbial Diversity in Bengal Tigers’.Co-authors of this study are Stanzin Dolker, Avijit Ghosh, Vinaya Kumar Singh, Bheem Dutt Joshi and Lalit Kumar Sharma, all affiliated with the ZSI, Kolkata.Thakur said they compared faecal microbiome samples from 10 captive tigers (seven male and three female) and seven wild tigers (all male) and analysed them alongside publicly available microbial data from three other subspecies — Amur, Malayan and South China tigers.“The findings revealed a clear distinction between captive and wild Bengal tigers. While captive animals showed an enrichment of bacteria associated with protein fermentation, wild tigers had a greater abundance of environmentally associated microbial groups. Wild Bengal tigers also recorded higher microbial richness and diversity,” said Thakur, adding that differences were not driven by sex. Male and female captive Bengal tigers showed substantial overlap in their gut microbial communities.The comparison across subspecies — 35 Amur, 12 South China, six Malayan and six Bengal tigers — showed that despite their evolutionary differences and geographical separation, tigers showed broad similarities in their microbial community composition. South China and Amur tigers, however, displayed lower microbial richness than Bengal and Malayan tigers.
