Dog Food is a highly prized memoir of the golden days when canines didn't attack people in packs, but rather served a social purpose in family households. Whatever health regulations were in place when these nutritional and historical treats were manufactured, they sure allowed for enough preservatives. Unopened Dog Food remains perfectly edible even beyond an apocalypse. Consuming it refills your character's Hunger bar by 16% and you Thirst bar by 5%.
Anyone interested in Dog Food can usually find cans of it in the residential houses of since-departed pet owners. Some cans have been spotted in hiking tents, fortifying the assumption that dogs were more than mere couch companions. Checking the local supermarkets can be fruitful as well.
WARNING: While the link between dogs and wolves is obvious, attempting to befriend a pack of wolves using Dog Food is highly dangerous. The wolves of Orca Island prefer a paleo-diet and thus insist on fresh ingredients with maximal nutritional value.