I took a set of my dog's photo and sent to the stock. They were accepted at first. Then I found the eye dischare and I can use lightroom to remove it. I removed it and sent them again but refused. I thought it should be allowed to modify a little so wonder why get rejected.
I think the focus is just a bit too soft, and the white balance is a touch out - it's just a bit too green for me. Sometimes this can happen. You send a photo in, it gets accepted; you delete it from your profile page, do a touch up, send it in again, and... it gets rejected!
IMO, both images have problems with focus, lighting & white balance and should not have been accepted the first time.
Also Stock inventory already contains millions & millions of high quality pet images. It's a highly competitive category that probably won't make many sales for you.