Featured Research

from universities, journals, and other organizations

Fetch, boy! Study shows homes with dogs have more types of bacteria

Date:
May 22, 2013
Source:
North Carolina State University
Summary:
New research shows that households with dogs are home to more types of bacteria -- including bacteria that are rarely found in households that do not have dogs. The finding is part of a larger study to improve our understanding of the microscopic life forms that live in our homes.

For the NC State study, citizen scientists in 40 homes sampled nine common surfaces to help researchers determine what kinds of bacteria lived there, and in what relative numbers. Here, one of the citizen scientists is sampling the surface of a cutting board.
Credit: Holly Menninger, North Carolina State University

New research from North Carolina State University and the University of Colorado shows that households with dogs are home to more types of bacteria - including bacteria that are rarely found in households that do not have dogs. The finding is part of a larger study to improve our understanding of the microscopic life forms that live in our homes.

Related Articles


"We wanted to know what variables influence the microbial ecosystems in our homes, and the biggest difference we've found so far is whether you own a dog," says Dr. Rob Dunn, an associate professor of biology at NC State and co-author of a paper describing the work. "We can tell whether you own a dog based on the bacteria we find on your television screen or pillow case. For example, there are bacteria normally found in soil that are 700 times more common in dog-owning households than in those without dogs."

And these microbial differences may be important. For example, it's known that women who have a dog in the home when pregnant are less likely to have children with allergies. This is a correlation - there's no known causal link between the presence of a dog and the absence of allergies - but it has been hypothesized that the difference is related to the women's exposure to a wider variety of microbes. However, to this point there were few data on what the differences in microbial populations might be. While this study doesn't demonstrate a causal link, it sheds more light on the subject, showing that dogs have a major influence on which microbes are found in our homes.

Citizen scientists in 40 homes sampled nine common surfaces to help researchers determine what kinds of bacteria lived there, and in what relative numbers. The nine surfaces were wiped with sterile swabs from which researchers collected DNA to see which organisms were present. The nine surfaces were the television screen, kitchen counter, refrigerator, toilet seat, cutting board, pillow case, exterior door handle, the trim around an interior door and the trim around an exterior door.

The study found 7,726 phylotypes, or kinds, of bacteria in the homes. The study also found that each of the locations sampled harbored its own unique collection of bacteria. Researchers were able to group the sampled surfaces in the homes into one of three general habitats: places we touch, places our food touches and places that collect dust. For example, the types of bacteria found in refrigerators, on kitchen counters and on cutting boards tended to be similar - because they were primarily linked to our food. Meanwhile, the bacteria found on doorknobs, pillow cases and toilet seats were also fairly similar - and came from humans.

"We leave a microbial 'fingerprint' on everything we touch," Dunn says. "Sometimes those microbes come from our skin, sometimes they're oral bacteria and - as often as not - they're human fecal bacteria."

The research also shows that the difference between habitats is greater than the difference between homes. For example, the bacteria on my pillow case are probably more similar to the bacteria on your pillow case than they are to the bacteria on my kitchen counter.

"This makes sense," Dunn says. "Humans have been living in houses for thousands of years, which is sufficient time for organisms to adapt to living in particular parts of houses. We know, for example, that there is a species that only lives in hot-water heaters. We deposit these bacterial hitchhikers in different ways in different places, and they thrive or fail depending on their adaptations."

The researchers are currently processing samples from another 40 homes, and are preparing to process samples from a national survey of 1,300 homes across the United States. The national survey sampled four sites in each home, representing the various habitats.

"The larger sample size will help us better understand the range of variables that influence these microbial ecosystems," Dunn says. "Does it matter if you have kids or live in an apartment? We expect the microbial populations of homes in deserts to be different from the populations of homes in Manhattan, but no one knows if that's true. We want to find out."


Story Source:

The above story is based on materials provided by North Carolina State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Robert R. Dunn, Noah Fierer, Jessica B. Henley, Jonathan W. Leff, Holly L. Menninger. Home Life: Factors Structuring the Bacterial Diversity Found within and between Homes. PLoS ONE, 2013; 8 (5): e64133 DOI: 10.1371/journal.pone.0064133

Cite This Page:

North Carolina State University. "Fetch, boy! Study shows homes with dogs have more types of bacteria." ScienceDaily. ScienceDaily, 22 May 2013. <www.sciencedaily.com/releases/2013/05/130522180311.htm>.
North Carolina State University. (2013, May 22). Fetch, boy! Study shows homes with dogs have more types of bacteria. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2013/05/130522180311.htm
North Carolina State University. "Fetch, boy! Study shows homes with dogs have more types of bacteria." ScienceDaily. www.sciencedaily.com/releases/2013/05/130522180311.htm (accessed October 31, 2014).

Share This



More Plants & Animals News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How A Chorus Led Scientists To A New Frog Species

How A Chorus Led Scientists To A New Frog Species

Newsy (Oct. 30, 2014) A frog noticed by a conservationist on New York's Staten Island has been confirmed as a new species after extensive study and genetic testing. Video provided by Newsy
Powered by NewsLook.com
Surfer Accidentally Stands on Shark, Gets Bitten

Surfer Accidentally Stands on Shark, Gets Bitten

AP (Oct. 30, 2014) A 20-year-old competition surfer said on Thursday he accidentally stepped on a shark's head before it bit him off the Australian east coast. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Ebola Inflicts Heavy Toll on Guinean Potato Trade

Ebola Inflicts Heavy Toll on Guinean Potato Trade

AFP (Oct. 30, 2014) The Ebola epidemic has seen Senegal and Guinea Bissau close its borders with Guinea and the economic consequences have started to be felt, especially in Fouta Djallon, where the renowned potato industry has been hit hard. Duration: 02:01 Video provided by AFP
Powered by NewsLook.com
Genetically Altered Glowing Flower on Display in Tokyo

Genetically Altered Glowing Flower on Display in Tokyo

Reuters - Innovations Video Online (Oct. 30, 2014) Just in time for Halloween, a glowing flower goes on display in Tokyo. Instead of sorcery and magic, its creators used science to genetically modify the flower, adding a naturally fluorescent plankton protein to its genetic mix. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins