In general, avoid buying dented cans. I've read that the sell-by dates on poultry can range from seven to 30 days after processing. This indicates that the chicken has never been frozen. Some chicken that looks fresh has been frozen and then defrosted. If there is more liquid in the package than the padding can absorb, it's not a good sign.
Ground turkey is especially perishable.
The sell-by dates for meat are often much shorter than for poultry. Ground beef is the most perishable meat, and in some stores it has just a one-day sale period. Use or freeze ground beef within a day or two of purchase. And remember, thawed meat stored more than one day, even in the refrigerator, tends to develop a high bacterial content. Buy fresh seafood from a retailer who specializes.