My two kittens are eating maybe 1/3 cup of kibble daily. The bag says they should be eating 1/2-3/4. They are also getting a tad bit of canned in each meal to coat the kibble with. Am I giving them enough? Half the time they dont even finish. I feed 4 times a day, 1 tablespoon of kibble mixed in with a tad of canned equals 1/3 cup over the day