You can sue both the manufacturer of the dog food and the seller (store where you purchased the dog food) for negligence and strict liability.  Negligence and strict liability are separate causes of action (claims) in your lawsuit.Negligence is the failure to exercise due care (that degree of care that a reasonable manufacturer would have exercised under the same or similar circumstances to produce a product that is not defective).Strict liability is liability imposed whether or not due care was exercised.This area of law is products liability.  Both the manufacturer and seller of the defective product are liable.  The store where you purchased the dog food is liable even if it could not have known the product was defective.Prior to filing your lawsuit, it may be possible to settle the case with the insurance carriers for the manufacturer and store.  If the case is settled with both insurance carriers, NO lawsuit is filed.  if the case is settled with neither insurance carrier, name both the manufacturer and store as defendants in your lawsuit for negligence and strict liability.  If the case is settled with one but not both insurance carriers, only name the party with whom the case has not settled as a defendant in your lawsuit.  If you are dissatisfied with settlement offers from the insurance carries, reject the settlement offers and file your lawsuit for negligence and strict liability.  If the case is NOT settled, you will need to file your lawsuit prior to the expiration of the applicable statute of limitations or you will lose your rights forever in the matter.