I don't know if it's because they are out of date or that's just the way they are, but they have an awful smell that my dog didn't like one bit.
All the best.
Far too hard and full of rubbish
We buy a lot of different treats / chews and these are by far the worst.
We persisted for a bit but our dog would not eat them. I tried breaking them into smaller pieces, still not bothered. Then tried soaking them in water to soften and so concerned about what they broke down in to that the whole bag has gone in the bin. A real waste but the colouring, large stringy pieces and clear lack of goodness was obvious and not surprised the dog wasn't keen.
I do not recommend.