optimum breeding temps?

Just curious what is the ideal breeding temp. to produce the most rat pups?

For some reason my rat collony has slowed down there production and I was thinking it was due to the tempeture of the room.

might be i read somewhere that rats thrive in a temp range of 60-70 degrees

Thanks het.pied.. I live in the cold country of Canada!!! I've been keeping them outdoors in a small barn. Deff. been keeping them cooler then 60, i'll have to heat the barn up with a register of some kind.

Around 70 is probably ideal. When its took cold the babies don't do as well and when its too hot the rats just lay around. 70 is ideal. Up to 80 is okay. In my experience anything over 80 makes the rats a little lazier.

I would definitely heat the barn. My rats are in the snake room, so they sit comfortably at 70-75 degrees. I would think that if you can get your barn up, even to 55 that would be good. Just make sure you give them plenty of bedding, I might even add something like cotton/pillow stuffing, if I were you.