[Susan]

Hi
Stop feeding the Stella & Chewy raw..
Find a free range human grade raw company or make your own raw diet with human grade raw meats/green veggies.
Sounds like the raw meat might be high in Toxins, Heavy Metals & Contaminates. Toxins can cause elevated ALT levels??
This was happening with my boy 2yrs ago when he ate a certain USA kibble he kept having elevated ALT levels..Then this USA pet food company was all over the internet being sued for their kibble being very HIGH IN TOXINS.
As soon as I changed his diet to a different brand his elevated ALT levels went back to normal.
My dogs Nutritionist who formulated my dog raw diet said to only use human grade meats I eat, she would NOT let me feed any of these Pre-made raw pet foods.
It’s worth a try changing diet & see what happens, also your dog needs to be on a large breed puppy diet till 2yrs old so his growing bones don’t grow too quickly & cause joint problems later on, if you have the money find a Nutritionist to balance him a raw diet made from Human grade ingredients + blended green veggies so diet is not too high in calcium and phosphorus & hopefully toxin free…
https://todaysveterinarynurse.com/articles/giant-expectations-nutrition-for-the-large-breed-puppy/