Science Diet A/D I thought was used for malnourished kitties/dogs - basically used when they need to gain weight. It would be very different from the Wysong Uretic, if you are comparing the two.
My cats only got a/d when they were very sick. Both my cats taht had it needed to gain weight and were very sick at the time. What do you want to use it for.
If you are asking because of crystals or uti's or blockages, my answer is neither food that you mentioned.
Canned foods no gravy as the system needs more moisture and dry foods if anything dehydrate. Best of luck