Kids who grow up with cats or dogs tend to get fewer respiratory infections during their first year of life, according to a new study from Finland.

Researchers followed 397 children from pregnancy through their first year of life, and found that those living with dogs developed 31 percent fewer respiratory tract symptoms or infections, 44 percent fewer ear infections and received 29 percent fewer antibiotic prescriptions.

Contact with cats was also linked with fewer infections, but the effect was not as drastic as contact with dogs - for example, infants living with cats were 2 percent less likely to need antibiotics.

"We speculated that maybe the dogs somehow can bring dirt or soil inside the house, and then the immune system is strengthened, or maybe it's something about the animals themselves," said study researcher Dr. Eija Bergroth, a pediatrician at the Kuopio University Hospital in Finland.

The link between pets and fewer infections held even when researchers took into account factors known to affect infants' infection rates, such as breast-feeding and number of siblings. Still, the researchers acknowledged that couldn't account for all such factors, and noted that they found a correlation, not a cause-and-effect relationship.