Animals don't stay in slope conforming pasture
This is possibly a bug in 1.76.

I used the slope conforming pastures, and some of the animals are wandering off to the SW corner of the map.  I realize that these are fenceless pastures, so perhaps I should not expect the animals to stay in them without building my own decorative fences around them.  However, these pastures seem most useful along the edge of the map where it's impossible to build fences.

I noticed this when my bannies started getting cold unexpectedly, and I found it was herdsmen wandering off in the middle of nowhere to get to the animals or laborers going to pick up the meat and leather.

Just posting in case anyone's still developing this.  Thanks for the fun mod!
It's a pathing issue because the slope is too steep in one area of your pasture or at the point your workers / animals would like to use to enter it. If it were a field, you'd have places too steep for farmers to walk on, so they couldn't finish the planting task in spring, which would prevent them from working further in the field, so no harvesting in autumn.

The slope-conforming things were added because they're fun and look good, but there's no way to make them "fix" the fact that slopes too steep aren't seen as valid pathing points and instead tend to send people and animals to map edges. You just have to be careful and reasonnable when placing them so you don't have pathing issue. Smile

So basically there's no real way to fix your issue on the modding side other than removing the slope conforming things or severely limiting them, so you'll have to destroy tha tpasture and remake it a bit smaller to avoid the super steep area.