"... hold back the hooded rats (the ones that are white and have black/brown/beige faces and shoulders, and typically with some black/brown/beige spots or stripes down their backs) to use as breeders mainly because those seem to have the least medical issues (or so I've read)..."
http://kark.motion-forum.net/t267-my-feeder-rat-colony

Agree? yes or no? If not, which ones do you hold back? and why?