I  have two dogs a 1.5 yr old Lab/Greyhound mix and a 13 yr old shepherd/rot mix.  I may have gotten a bad/stale bag(s) of food. I use both Iams and Nutro Natural Choice and mix the two. Recently my lab mix was off her feed, vomited and was constipated. I started feeding her brown rice, chicken and green beans which seems to have helped. She got better so I started with the kibble again but mixed it with green beans but my son said he saw vomit with green beans in it.
Now, my 13yr old has gone off his feed which I was giving him kibble with green beans too (no playing favorites) and he has always had a sensitive stomach. Vomit may have been his but he is more known for what I call "south end explosions".  What to do. I made up some brown rice, chicken and carrots to give them for a few days. When should I start to mix kibble in with it. I also thought I'd just introduce one brand back into their diet without mixing. Do you suggest one that would fit better than the ones I listed?  Should I consider introducing wet food to make up for any possible nutrient loss with the homemade food? They both were getting wet food about a month and a half ago because the 13 yr old had a possible stroke issue and he wouldn't eat. The vet gave a prescription for 7 days and then I switched to Nutro Natural Choice Wet food and it seemed to work. I used the wet food that had strong odor and taste and that was for sensitives stomachs. Couldn't find sensitive stomach and senior combined.  Did I create sensitive stomachs by using the wet foods too much or was it a bad bag of food or some possible virus?

Please help

I didn't find the right solution from the internet.

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