The dog food is fine however I would stay away from the seeds as a staple diet, every now and then as a treat it's fine but you really want them to eat what's good for them in term of breeding and producing feeders (obviously like people animals do not know what's best for them

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I will tell you what I do and you can make your own call, I have started breeding feeders mice and rats in 2007 and I produce several thousands every year, my goal is to produce feeders and have healthy breeders.
When I first started I did like everyone else started buying Mazuri 6 F designed for feeder breeders. At the time my observation were normal size litters however my issue is that many of my females were developing mammary tumors, about 20%/25%. At the time I decided to do an experiment and try Doggy Bags from tractor supply ($12.99 for 40 lbs), I had heard mixed reviews but I like to try things and see for myself.
I kept half of my colony on Mazuri and Half on Doggy Bags for a year, and I was very surprise of the results since many people were looking down on dog food, my rats were not greasy or smelly (well not more then the usual, not like they smell like roses anyway), litter size was the same or better and the mammary tumors rate significantly dropped, it is now very rare for me to have a female with a tumor, I would say 2% a year now.
Obviously that side by side test lead me to switch to Doggy Bags completely, what I look at is a diet of 18% Protein and not too high in fat and also no red die.
Obviously 100000 of thousands of feeders later and a healthy group of snakes later, I would not change a thing.