The wargs will go for the meat at ~50% morale, however only certain (trash-)wargs do that, some of them will never eat. Also if multiple wargs head for the same meat only one will eat it and the others will resume fighting when it's gone, so you need to be careful with AoE. As others have said, stuns are also a no-go.
And the meat doesn't just heal them, it also makes them hit much harder/faster.
Used to play: 85 Champ / Captain / Runekeeper / Guardian, Guild Master of everything but cooking.
Playing now: Hellcat / King Tiger / GW Panther / IS / KV-5 / M4 Sherman and more