We have a mixed flock of 12 hens that are 9 mths old. We would like to get a rooster for the girls now. What is the best way to introduce him into the flock? Should I keep him separate but in view of them for a few days, to make sure he is not bringing anything creepy into the group? So far we have not had any illnesses with our girls. Also how many hens to rooster should the ratio be? All help to make a smooth transition will be appreciated. We are schedule to pick him up on January 2, 2009. Thanks for your help!