Navezgane has many different animals to hunt, kill, and harvest. Most common animals like a Stag, Chicken or Rabbit will flee from the player if they see or hear them. Other rarer types of animals like the Wolf, and Bear will attack you on sight. Neutral animals will only attack if they are attacked. There are some animals that have been infected and have become Zombie animals; these animals will provide Rotting Flesh instead of Raw Meat and will still provide Bones, Leather, and Animal Fat. Only Bears will provide an extra resource called Testosterone Extract when harvested.
A Bone Knife, Hunting Knife, and Machete will always be the best tools to harvest any animal as they can provide the player with extra resources. It also as a small benefit of leveling the player's skill level with Bladed Weapons.