My gnomes completely slaughtered 2 of my 3 pastures without orders

[EngineOfCreation]

I have 3 pastures, one each for yaks, alpacas, and emus. All of them were full, I set them to 1 male, rest female. I haven't been watching them at all for quite a few days since everything was running smoothly and I focused my attention on mining. However, just now I checked and the yak and alpaca pastures were completely empty! My butcher shop is set to automatically slaughter excess livestock, but I haven't touched the pasture settings at all, they're just gone. Is that a known issue?

[SoonTiaxRules]

You may have run out of straw. If you run out of food for livestock they'll eventually wander away. Since your emu stayed (I assume), then lack of straw could be the cause.

[Arryu]

Make sure they had enough wheat straw. It sounds like you ran out and they all left the map while you were distracted.

[EngineOfCreation]

Yes, unfortunately that was the problem. Good call.