A researcher and his coauthors out of Sweden conducted a study that was published by JAMA Pediatrics. They wanted to see if early exposure to a dogs or farm animals decreased the risk of asthma in children.
The sample size for this study included over one million children from Sweden that were born from 2001 through 2010. They used registry data to determine the presence of animals as well as the asthma medication and diagnosis.
They found that at age six, kids had a reduced risk for asthma if they had been exposed to dogs or farm animals in their first year of life. 4.2 percent of the study group had an asthmatic event during their seventh year of life the study found.
The results indicate that dog exposure during the first year of life was associated with a 13 percent decreased risk of asthma in school-age children. Farm animal exposure was associated with a 52 percent reduced risk of asthma in school-aged children and 31 percent reduced risk in preschool-age children respectively.
A couple caveats the researchers noted were the results were independent of parental asthma as well as whether or not the child was first-born.