STRINGS.CODEX.CRITTERSTATUS.METABOLISM.BODY.CONTAINER1
A critter's metabolic rate is a measure of their appetite and the materials that they excrete as a result.
Critters with higher metabolism get hungry more often. Those with lower metabolism will consume less food, but this reduced caloric intake results in fewer resources being produced.
The digestive process is influenced by conditions such as domestication, mood, and whether the critter in question is a juvenile (baby) or an adult.