The researchers also found that the differences in gut microbial communities affected the expression of genes associated with the piglets' immune system.
Animals raised in the isolated environment expressed more genes involved in inflammatory immune responses and cholesterol synthesis, whereas genes associated with T cells were expressed in the outdoor-reared pigs.
Kelly said that until now, the link between living environment and immune response had been circumstantial.
"There has been a lot of hearsay around gut microbiota and how it influences immune function and susceptibility to diseases and allergies," Nature quoted her as saying.
The latest work establishes a strong causal link.
However, Glenn Gibson, a food microbiologist at the University of Reading, UK, said that because the study was carried out in pigs, it is not certain that the results are relevant to humans.
Kelly argues that the similarities between the organisms found in human and pig guts and their comparable size in organs, makes pigs a good model animal to study.
The study has been published in BMC Biology1.
Source-ANI
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