Milk is inhabited by a community of bacteria and is one of the first postnatal sources of microbial exposure for mammalian young. Bacteria in breast milk may enhance immune development, improve intestinal health, and stimulate the gut‐brain axis for infants. Variation in milk microbiome structure (e.g., operational taxonomic unit [OTU] diversity, community composition) may lead to different infant developmental outcomes. Milk microbiome structure may depend on evolutionary processes acting at the host species level and ecological processes occurring over lactation time, among others. We quantified milk microbiomes using 16S rRNA high‐throughput sequencing for nine primate species and for six primate mothers sampled over lactation. Our data set included humans (
Environmental and ecological factors, such as geographic range, anthropogenic pressure, group identity, and feeding behavior are known to influence the gastrointestinal microbiomes of great apes. However, the influence of individual host traits such as age and sex, given specific dietary and social constraints, has been less studied. The objective of this investigation was to determine the associations between an individual's age and sex on the diversity and composition of the gut microbiome in wild western lowland gorillas.
Publicly available 16S rRNA data generated from fecal samples of different groups of
Both age and sex significantly influenced gut microbiome diversity and composition in wild western lowland gorillas. However, the largest differences were observed between infants and adults in habituated groups and between adults and immature gorillas within all groups, and across dry and wet seasons. Specifically, although adults always showed greater bacterial richness than infants and immature gorillas, network‐wide analyses showed higher microbial community complexity and modularity in the infant gorilla gut. Sex‐based microbiome differences were not evident among adults, being only detected among immature gorillas.
The results presented point to a dynamic gut microbiome in
- NSF-PAR ID:
- 10461569
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- American Journal of Physical Anthropology
- Volume:
- 169
- Issue:
- 3
- ISSN:
- 0002-9483
- Page Range / eLocation ID:
- p. 575-585
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Homo sapiens , Philippines and USA) and eight nonhuman primate species living in captivity (bonobo [Pan paniscus ], chimpanzee [Pan troglodytes ], western lowland gorilla [Gorilla gorilla gorilla ], Bornean orangutan [Pongo pygmaeus ], Sumatran orangutan [Pongo abelii ], rhesus macaque [Macaca mulatta ], owl monkey [Aotus nancymaae ]) and in the wild (mantled howler monkey [Alouatta palliata ]). For a subset of the data, we paired microbiome data with nutrient and hormone assay results to quantify the effect of milk chemistry on milk microbiomes. We detected a core primate milk microbiome of seven bacterial OTUs indicating a robust relationship between these bacteria and primate species. Milk microbiomes differed among primate species with rhesus macaques, humans and mantled howler monkeys having notably distinct milk microbiomes. Gross energy in milk from protein and fat explained some of the variations in microbiome composition among species. Microbiome composition changed in a predictable manner for three primate mothers over lactation time, suggesting that different bacterial communities may be selected for as the infant ages. Our results contribute to understanding ecological and evolutionary relationships between bacteria and primate hosts, which can have applied benefits for humans and endangered primates in our care. -
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