Washington, Dec 17 : Scientists have discovered why children's propensity for developing allergies and asthma is considerably reduced when they are exposed to pets in early infancy.

In experiments conducted on mice, researchers have found that exposure to canine pets can reshape the gastrointestinal microbiome -- or the community of microbes that live in one's gut -- thereby enhancing one's resistance to various allergens.

Researchers found that exposure of mice to dust from houses where canine pets are permitted both indoors and outdoors can re-shape the community of microbes that live in the mouse gut, collectively known as the gastrointestinal microbiome.

It can also diminish immune system reactivity to common allergens, according to a new study by researchers led by Susan Lynch, associate professor with the division of Gastroenterology at U. C. San Francisco, and Nicholas Lukacs, professor with the Department of Pathology at U. Michigan.

The scientists also identified a specific bacterial species within the gut that is critical for protecting the airways against both allergens, and viral respiratory infection.

The current study demonstrates that changes in the gut microbiome can have wide-reaching effects on immune function beyond the gut, at sites elsewhere in the body, Lynch said.(IANS)