What are you feeding and how old are your rats?

My first 2 litters were only 4 because I was feeding a brand of rat feed that isn't well-known and it was getting old. Mazuri is $40-$50 here for 20lb, and that's more than the grain-free I feed my cat, so I went with something cheaper... it was a mistake...

I changed over to Native earth last month and my latest litter(last night) was 14 pups!