My pug has a stinky sore and looks infected (yellowish), that just appeared. I have two dogs and thought maybe a fight, but i don't believe so. The only thing that has changed is his food (was Nutro now Purina). The sore stinks, I have put neosporin on the sore after I cleaned it with a prep wipe from my first aid kit and gave him a cephlexin antibiotic pill that I had some left over from awhile back (from our vet). Our vet is closed till Monday, any ideas what it can be? I havent encountered this sort of sore on his neck before, I thought maybe a bad hot spot or harness was rubbing but we took that off.
He doesn't seem in any pain. I have a photo: