I have a very active 1-year-old golden retriever/Australian shepherd mix. He loves chewing on bones, but he can be occasionally food aggressive towards my partner and I, and our other dog. We control when he has access to food, but we'd like him to have something that he can chew on to occupy himself when we're busy.
At a friends' house last weekend, he was chewing on a fake plastic bone. I noticed that this kept him interested, just like a real bone, but he wasn't being defensive with it (he does not defend toys at home, just bones and food).
I'd like to get him something like this to play with, but would prefer to avoid plastic both for environmental and health reasons (he's found to ingest some plastic which doesn't sound healthy). I'm wondering if there are other alternatives beside plastic? For instance, I remember seeing antlers at a pet store. Does anyone have any experience with these, or something else?