I have a one year old GSD mix. I think its a mix because it have a very thin tail and very short hair with no undercoat. When we got him is was a bit thin but that wasn't realy a concern.
We fed him for a year, twice a day, with Kirkland Supper Premium Puppy food ( the yellow bag). Of course he grew, he is a good size bu i think he is very thin.
Now, he is 12 months- i weight him today - 82 lbs. 3 Weeks ago we switched to the Kirkland Premium ( green bag). I chose Kirkland because dogfoodadvosor says it has 4 stars and almost no additives.
We have been to the vet- no worms. The vet just says he is naturally skinny.
What are your suggestions.