i got a bunch of weaned rats today and upon inspection it seems that one of them is either not quite weaned or perhaps malnourished and quite lethargic. it is the same size as the others but very thin and doesn't open its eyes all the way. while these are feeders i don't really want to just feed it off because i prefer to feed my snakes nice fat rats. is there anything i can do to plump this little one up and bring it up to where it needs to be? it seems to be able to eat the food mix that i give the others but it mostly wants to sleep. perhaps a puppy formula would help? i have heard of giving them soy milk--i have rice milk in the fridge--would that be something good to warm up for it?