i think the best option would be to call a veterinarian and ask what the proper nutrition should be.
seems like most of the answers here are NOT answering the question, rather telling the OP to get rid of the rat, disease issues etc. we might want to stick to the topic and assist if we have a suitable suggestion.
seems like most of the answers here are NOT answering the question, rather telling the OP to get rid of the rat, disease issues etc. we might want to stick to the topic and assist if we have a suitable suggestion.