My cat Mandie is 15. She's indoors as well. What are the calories needed for an old girl?
It would depend how active she still is. If she's still expending a good amount of energy everyday, I would feed her like any other adult aged cat based on her weight and activity level. We have an 11 year old 12.5lb indoor cat, but he still tears around the place and is quite skinny (with what Dr. Kris has referred to as "skinny butt", even though he looks very big because of all the skin and fur) so I tend to feed him more like a kitten, more frequently and more calories, pushing 300.
inactive cats may only need 18 kcalories per poundMandie isn't very active. She plays sometimes but mostly sleeps.