they really dont need too many treats when they are young. Once a week I would say. More as they get older. I tend to place Kale and the yogurt in a blender. Once grinded i stir in a bunch of raw oatmeal. cooked and ground up potatoes, and/or rice. Any table scraps, chopped up fine as well...so when I place it all on a toast pan and place it outside, they will get the nutrients from it all no matter what they chomp at.
Just remember rice alone has very little nutrients for them in it at all. Raw Kale, Broccoli, cabbage, etc have the good vitamins they need so try to include it as well. White potatoes are to be cooked before feeding it to them. But sweet can be given in any condition, i personally cook it for them cause I serve more of a mash blend of things.