Tina, for your Golden & Corgi, getting weight off them is of the utmost importance, for their joints. I used Wellness Core Reduced fat with great success. While I have not used it, others have had luck with Annamaet Lean (this may need to be ordered as it’s not as widely available). Both can benefit from salmon oil added to their diet. You can use human form or buy those available online or at pet stores for dogs (I use human). Are they getting a supplement for their joints?
For the cocker & mixed breed, I’ve read that people use Nutri Source with good luck for dogs with sensitive stomachs.
I know nothing about colitis but hopefully someone else can answer. Its possible the foods I listed won’t work. If I was you, with dogs with issues, I’d consult a holistic vet who would be able to advise you on dogs with their issues and probably offer a non vet food. You could go to DogAware.com and contact Mary Strauss from there or Lew Olsen at b-Naturals.com.
Both of them could give you some advice. Good luck!
