I'm sorry I just read what you said and I'm lost your breeding 288 rats and only 6 on average are giving birth???
Now all of this is on average
You said
So at an average of 10 a littler thats 6 moms on average a weeks giving birth.
But you said that
72 tubs with 0.4 in it is 288 females with no resting in between breeding and your not separating them you only getting, per month on average 24 females a month...so your birth rate is 8.33% success rate?? on average??
Or is this for a smaller group than the whole collection??
My humblest apologies I just saw the per rack bit..
My bad
When you've got 10,000 people trying to do the same thing, why would you want to be number 10,001? ~ Mark Cuban