Pet exposure may reduce allergy and
obesity

Research shows having
a dog early in life may alter gut bacteria in immune-boosting ways

Date:

April 6, 2017

Source:

University of Alberta Faculty of Medicine
& Dentistry

Summary:

If you need a reason to become a dog lover, how about their
ability to help protect kids from allergies and obesity? A new study showed
that babies from families with pets — 70 per cent of which were dogs — showed
higher levels of two types of microbes associated with lower risks of allergic
disease and obesity.

If you need a reason
to become a dog lover, how about their ability to help protect kids from
allergies and obesity?

A new University of
Alberta study showed that babies from families with pets — 70 per cent of
which were dogs — showed higher levels of two types of microbes associated
with lower risks of allergic disease and obesity.

But don’t rush out to
adopt a furry friend just yet.

“There’s
definitely a critical window of time when gut immunity and microbes co-develop,
and when disruptions to the process result in changes to gut immunity,”
said Anita Kozyrskyj, a U of A pediatric epidemiologist and one of the world’s
leading researchers on gut microbes — microorganisms or bacteria that live in
the digestive tracts of humans and animals.

The latest findings
from Kozyrskyj and her team’s work on fecal samples collected from infants
registered in the Canadian Healthy Infant Longitudinal Development study build
on two decades of research that show children who grow up with dogs have lower
rates of asthma.

The theory is that
exposure to dirt and bacteria early in life — for example, in a dog’s fur and
on its paws — can create early immunity, though researchers aren’t sure
whether the effect occurs from bacteria on the furry friends or from human
transfer by touching the pets, said Kozyrskyj.

Her team of 12,
including study co-author and U of A post-doctoral fellow Hein Min Tun, take
the science one step closer to understanding the connection by identifying that
exposure to pets in the womb or up to three months after birth increases the
abundance of two bacteria, Ruminococcus and Oscillospira, which have been
linked with reduced childhood allergies and obesity, respectively.

“The abundance of
these two bacteria were increased twofold when there was a pet in the
house,” said Kozyrskyj, adding that the pet exposure was shown to affect
the gut microbiome indirectly — from dog to mother to unborn baby — during
pregnancy as well as during the first three months of the baby’s life. In other
words, even if the dog had been given away for adoption just before the woman
gave birth, the healthy microbiome exchange could still take place.

The study also showed
that the immunity-boosting exchange occurred even in three birth scenarios
known for reducing immunity, as shown in Kozyrskyj’s previous work: C-section
versus vaginal delivery, antibiotics during birth and lack of breastfeeding.

What’s more,
Kozyrskyj’s study suggested that the presence of pets in the house reduced the
likelihood of the transmission of vaginal GBS (group B Strep) during birth,
which causes pneumonia in newborns and is prevented by giving mothers
antibiotics during delivery.

It’s far too early to
predict how this finding will play out in the future, but Kozyrskyj doesn’t
rule out the concept of a “dog in a pill” as a preventive tool for
allergies and obesity.

“It’s not
far-fetched that the pharmaceutical industry will try to create a supplement of
these microbiomes, much like was done with probiotics,” she said.

Story Source:

Materials provided by University of Alberta Faculty of
Medicine & Dentistry. Note: Content may be edited
for style and length.