Occurrence: Worldwide. Species affected: All. Age affected: All.

Causes: The Norwegian rat (Rattus norvegicus) and the house mouse (Mus musculus) are the most common rodents found around poultry houses.

Effects: Rats and mice cause damage to buildings and their foundations through chewing and burrowing activities. Both will eat poultry feed, and rats may also eat eggs in laying houses. Rats and mice are common vectors for many viral, bacterial an...