Portion Sizes for Homemade Dog Food

Hey all, we took our almost-13 year old Newfoundland into the vet yesterday for a checkup/urine test/bloodwork (we think she may have a UTI). While we were there the vet found some kind of cyst on her gums which most likely resulted from a broken tooth. The cyst had already worked its way out not far away, so there's no danger of it going into a more dangerous area. However, we've decided not to get surgery for it (pulling the tooth, sewing up the area) due mostly to its cost, the danger of her not surviving the anesthesia, and the simple fact that she's very old and most likely doesn't have that much time left anyway. The vet says it doesn't pose any real threat to her and put her on the same anti-biotic that's being used to treat her UTI.

We're going to start her on a diet of our own homemade food to make it easier for her to chew. She's eaten dry food for her entire life as it's better for dogs and wet food has never agreed with her. The food we're making for her is a combination of white rice, peas, 85% lean ground turkey (the fattiest they had in the store), and some unsalted chicken stock mixed in for good measure. There's no sauce, salt, or seasoning being added to keep it gentle on her.

My question is this; how much homemade food equates to one cup of dry food? She's about 92 pounds (at her healthiest she was 110, but her muscles have naturally atrophied) and has always eaten just under 2 cups of dry food per meal. We want to keep that amount and will be continuing to feed her dry food mixed in, but need a ratio to know how much to feed her. Thanks!