This is melamine. Melamine is the substance that was found in the gluten supply imported from China, causing the recall of a whole lot of brands of dog & cat food. It's a strong base, meaning each one of those N's (both the peripheral ones and the ones in the ring) can hold onto one more H than it has in the illustration. When heated melamine looses nitrogens, leaving guanidine, a muscle stimulant used as a pharmaceutical, and ammonia, a poison. One wiki-contributor said the animal's symptoms were consistent with ammonia poisoning. The FDA was is supposed to regulate animal food safety but had never set food inside the plant where the poisonous food was produced.
And on the pet food recall:
I was feeding Shakti the Nutro brand dry food. Shakti liked that food. She doesn't like the new kind as well...