WoW Classic – Why Does My Pet Take So Much Food to Eat and Why Does It Run Away?
Hunters must take good care of their pet. They require up-to-date food to keep them happy. Feed them food close to their level or raw meat that drops from mobs near their level. Your pet has loyalty ranks that determine how hungry it gets as well.
If you don’t feed your pet for a while and it becomes unhappy for 30 minutes at loyalty rank 1, it will run AWAY. You cannot call it back, and it is gone. Make sure you keep it fed if you intend on keeping it. Pets do not take lightly to malnourishment.
If you are using a UI addon, sometimes they do not have pet happiness integrated into it. The character pet info tab DOES NOT show pet happiness, only beside the pet frame by default. For those using ElvUI, you can go into the settings > Unitframes > Pet > Custom Texts > type in [happiness:icon] then hit okay.