http://www.itchmo.com/read/recall-hb...-pets_20070613

They said in the beginning of all the recalls: melamine is used to bulk up the protein in dog, cat, fish, rodent, and livestock foods. I didn't think they'd bother recalling rodent or fish food simply because the animals have little value to us and we normally don't do necropsies to find out why Nemo died. I think many large scale aquariums have been seeing deaths due to the food though so they had to recall to avoid business lawsuits.