When making stock from chicken or turkey carcasses upon which little meat is left, there are two points to be made:
First, use them quickly, without waiting for them to get dried up and stale.
Second, it is a mistake to cook them too long, or a strong and unpleasant flavor of bone will result (this is what makes pressure-cooked stocks so horrible) and the stock will be cloudy. Whenever possible, it is a great improvement to add a small portion of raw veal or beef when making such stocks, and to add onions, carrots, celery and herbs.
~~ Elizabeth David