Hi ya Everyone: Today Randy and I were at my vets to drop off a ferret to be spayed and while we were there they donated a bunch of food to the shelter and one of the items was a case of Hills C/D. My vet was very busy so could not take the time to explain what this is used for or what the difference between this canned food and A/D is. From reading the label and comparing the percentages in C/D by and large are higher but the ingrediants are not the same. Can anyone please tell us what this is used for and which is better and why? Thannkx, Cindy [Posted in FML issue 2599]