In a few months I am bringing home a 16 year old rescue, Shepherd-possible husky mix. He's very healthy, no problems, I expected arthritis but he weirdly is incredibly healthy. Apart from his teeth, which will be taken care of when he comes home. Not only did he get the all clear from their vet but also from mine. I want to keep him healthy by feeding him the best food possible. What do you guys recommend? thank you!!