I am preparing a project of enrichment of captive Sun bear. There are two sun bears staying together in the zoo, both of them are 3 years old, one is female, another one is male. The female one sucks its hand all the time. I am wondering whether the feed is enough for them or not ( about pellet feed 1 kg per day for them, and some furits).  I could not find the review paper about feed nutrition standards and feed intake of Sun bear. Is there any one could give me some suggestion? Thank you.