Thank you Amethyst, for the good suggestions.If you are feeding a good quality pellet and hay there is no need to feed critical care, the pellets should have all the nutrients the chin needs, extra tends to just be wasted and pooped or peed out. The only time it might be beneficial to give to a chin that is otherwise eating on it's own would be if you get a chin from a bad situation that is malnourished and/or underweight, then the vet might suggest adding some critical care to help the chin gain back weight and strength. Giving some once in a while as a treat wont really hurt though, and is a good way to make sure your chins actually like it if they have never had it before, should you ever need to feed it to them. I know some people even make it up with just enough water to make a thick paste, and then bake it into little cookies for them. The cookies are also a good way to get rid of the critical care you might have on hand that is getting close to expiring so you aren't wasting it.