Sleeping on animal skin may reduce a baby's risk of developing asthma.
Germs in the hide and fur prime the immune system not to trigger allergies, scientists believe.
The finding comes from a study of 2,441 healthy German babies whose progress was monitored until the age of 10.
More than half (55 per cent) slept on animal skin during their first three months of life.
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They were 79 per cent less likely to develop asthma by six years of age than children not exposed to animal skin.
The results, presented at the European Respiratory Society's International Congress in Munich, lend support to the "hygiene hypothesis" that suggests too much cleanliness early in life can increase susceptibility to allergies.
Lead researcher Dr Christina Tischer, from the Helmholtz Zentrum Munchen Research Centre, said the results supported earlier research.
"Previous studies have suggested that microbes found in rural settings can protect from asthma. An animal skin might also be a reservoir for various kinds of microbes, following similar mechanisms as has been observed in rural environments.
"Our findings have confirmed that it is crucial to study further the actual microbial environment within the animal fur to confirm these associations."