It might be time to bite the bullet and trial bringing elements of the farmyard indoors, an asthma expert from New Zealand has suggested.

Professor Julian Crane from the Wellington Asthma Research Group was commenting on a study of almost 2,500 children from Germany that found infants who slept on animal fur were less likely to report wheezing and asthma in later childhood.

In a sub-group of these children, their peripheral T-cells made more interferon-γ (T-helper cell (Th)1 response) than children who did not sleep on furs, reported the authors in the European Journal of Respiratory Medicine.

Sleeping on animal fur was also associated with reduced atopy at 10 years of age in this subgroup, results showed.

Animal fur could be an effective means of creating environments associated with higher microbial exposure, the researchers concluded.

Writing in an accompanying editorial Professor Crane said the findings of the current study, together with other research showing a protective effect from a wide variety of early infant practices and exposures, raised the question of whether the farmyard should be brought indoors by exposing infants to multiple human, animal and microbial products “in a manner that is both safe and immunostimulatory.”

“The alternative is to wait until all of the relevant immunobiology is understood and characterised, but this may be a very long wait indeed. Furthermore, the hypothesis may be wrong and in the end only randomised trials will provide sufficient evidence to change practice,” he concluded.