US-based Megainin Pharmaceuticals Inc researchers have found a natural antibiotic in the tongue of the cow which may explain how injuries caused to the animal's tongue remain infection-free and heal rapidly.

The researchers isolated a compound -- lingual antimicrobial peptide (LAP) -- capable of killing bacteria and viruses. They say lap is produced through the action of a gene active in the cells that cover the upper surface of the bovine tongue.

Similar compounds have not yet been identified in humans, but the researchers suggest that all vertebrates may have cells within their mucus membrane tissues producing natural antibodies.