Quote Originally Posted by suzuki4life View Post
your use of 2x3's and spacing costed you the 6th tub.

so yes you gain more food capacity, but you cost yourself space which it most valuable.

my design is 6 high and I have switched to dual valves per tub.
Space is something that I don't really have to worry about. I am fortunate to have a VERY LARGE space to breed my rats.

My main efforts not go into making the work it takes to maintain my colony go as quickly as possible. This means that larger food hoppers, larger water reservoirs, and more ventilation/less animals per tub, give me more time in my week to do other things.

I'm running my feeder colony at 1.4 animals per tub, or 5.20 animals per rack. I am finding that giving the rats more space is greatly increasing the survival rate of the pups when kept in a colony setting. I can fit 50.200 animals in a 12' x 12' space with PLENTY of room for cleaning etc. 200 females are going to produce about 2000 rats per month for me in this set up. I am averaging 10+ babies per female making it to weaning size running 1.4 in the large mortar tubs.

I am still separating my more valuable animals into birthing tubs and will continue to do so until I have breeding animals that are exclusively homozygous for the traits that I want. I don't really want to breed a rat and have her lose two babies when the two babies that she loses could very well be the two blue dumbos in the litter. However, once I have a few hundred more blue dumbo breeding animals I will probably run them in the 1.4 ratio in the large tubs as well.

So, long story short. There is no BEST way to build racks. There is no BEST ratio of males to females. It really all depends on what you want to accomplish.

I could probably do an entire HOURS LONG presentation on rat breeding methods. Its possible that some day I might do a full out post on the subject. Chances are that it will probably be a book though LOL. Maybe a series of DVDs? LOL.