http://www.bbc.co.uk/nature/life/Brown_rat BBC Nature - Brown rat videos, news and facts multiply to 200 http://www.bbc.co.uk/nature/life/Brown_rat Rattus norvegicus BBC Nature - Brown rat videos, news and facts BBC multiply to 200 http://www.bbc.co.uk/nature/life/Brown_rat Rattus norvegicus multiply to 200 multiply to 200 BBC Nature - Brown rat videos, news and facts http://www.bbc.co.uk/nature/life/Brown_rat multiply to 200 http://www.bbc.co.uk/nature/life/Brown_rat multiply to 200 multiply to 200 Brown rat BBC multiply to 200