I found this on a website selling rats and mice. I heard this before and I am sure it has been shared but if not then here you go. I am not advertising for anyone so I took out all the stuff referring to their business. I am just trying to share the knowledge. If you know something different then please go ahead and share.
Toxic Mice - Where did all the red dye go?
"Dog Food Feed is Killing our Snakes" says Jim Jackson of Snake Asylum, Cicero, Il.
90-95% of the mice and rats breeders feed dog food only, and the cheapest brand available. The mice are absorbing the large quantities of red dye into their organs. Their metabolism is twice as fast as ours. They can't eliminate it, and must store it in their organs. This red dye, put into the dog food to enhance it's meaty appearance, of course is passed on to the snakes. What happens is that the red dye kills off the snakes kidneys and gaul bladder, and can cause tumors. Jim and his friends are doing extensive research on this , and if they are right, this will explain the mysterious deaths of otherwise healthy reptiles.
Parts is Parts
Bargain mice are out there, you just have to make sure that they have all of their organs. Some lab rats have had their reproductive parts, brains and other major organs removed. Some have been bleed for blood serum. Some have been put on special diets to deprive them of certain nutrients. Some have had cancer tumors kidney failure and arterial sclorosis induced, other have been injected with some pretty serious drugs.
My Snake Won't Eat Frozen Mice or Rats
People who tell me that are buying frozen mice trays in zipper lock bags. Sure their snakes won't eat them, because often they have been sitting in the breeders freezer for 4 to 6 months and are freezer burned before you get them. Be sure you seller has a stock of fresh food. If you heat up he rat and it falls apart then you might want to start asking questions.
Blood Sucking Parasites
A mouse breeder in N.E. Florida boasts that he doesn't have any trouble with mites, because he dusts the cage wood shavings with this powder that kills them. Obviously, he doesn't have a clue that the mice will either eat it, or get it in their system, through their skin.
A clean sanitary enviroment is necessary, but I don't care how careful you are, parasites happen. That is why I preach, freezing kills all blood sucking parasites dead, "deader is better,". That is why I freeze parasites, not poison them.
Beware of Amateurs
A veternarian told me he once ordered some bargain pinkies, 20 cents each. But it was CO shipping cost. When they arrived, he saw that they had put them in a styrafoam cooler and frozen them in a block of ice. The shipping cost was $65.00 COD.