Something I learned this year (after having cats nearly all my life): cats can get diabetes and overeating will do it, due to high carbs in dry food.
My vet has wanted me to give the cats more wet food, ideally only wet food. She says you don't see cats in the wild eating grains. I'd been giving them wet every other morning (3 cats sharing a 3 oz can). I was worried they would get finicky or overeat the wet if I gave them more, or there would be one cat pushing another away. The vet said wet food 1) gives them more moisture (leaving water out in a bowl isn't enough) and 2) will satisfy their hunger better than dry.
With the 2 brothers I've always had trouble finding the right dry food that they wouldn't throw up after a while. They've been getting grain-free dry food for a while now & there's been a lot less vomit. But it's very expensive (over $30 for a big bag compared to maybe $12/15 for Purina or another brand found in grocery stores).
A couple/three months ago (because the vet said the boys were FAT) I started taking up the food bowl at night & began giving them wet every morning (now 3 cats share a 5.5 oz can). The dry goes down now around the time I get home from work.
All 3 cats have lost weight (the vet said they would eventually get down to a more natural weight). It wasn't as traumatic as I thought it would be (only 1 cat cries every time I'm in the kitchen but that's not a change for him). When the dry goes down they all come and take a few bites then walk away. (The vet did say the wet would satisfy them more.)
Soon I'll try giving them wet twice a day and keep the dry only for those times when I go away for a few days and don't have someone come in to feed them.
I found an interesting website all about the issue. My cats are getting Friskies Pate, which is one of the OK commercial wet foods listed on this site. I'm not about to get into grinding up mice meat and filling my freezer with cat food.
