Pen animals

Pen animals, or farm animals, are animals with special rules in regards to habitat.

Summary

Pen animals do not respect regular zones. Instead, they must be roped into an enclosed area, known as a pen, and designated by a pen marker. For pen animals, fences and fence gates are impassable, but animal flaps are considered open. Other terrain, such as walls and doors, can also be used to enclose a pen, which will help enemies from breaking open the pen as easily (although pen animals will never be attacked directly). Walls however cost 5x as many materials to build, and can't be stepped over. Additional, players will need to make sure roofs aren't being, or they'll collapse in larger pens, and stop grass from growing.

Outside of a pen, or if the pen has an open door, animals will enter into the roaming mental state. Roaming animals will wander away and eventually leave the map. They can be roped into a caravan hitching spot or a pen (closed or not) by a colonist with enough animals skill for that animal.

In general, pen animals can eat hay, and graze on grass and other naturally growing vegetation. They all have 0 trainability. These are not traits of being a pen animal, but all pen animals have these traits.

Pen animals will not actively be targeted by raiders (though can be caught in the crossfire).

Strategies

Pen in combination with auto-slaughter can be extremely powerful to reduce the amount of micromanagement done by the player. The use of pens and auto-slaughter is a necessity for any colony with the rancher meme .
When choosing a pen animal to farm, you may want to consider animals that have more purpose than their meat. For example muffalos can provide wool and can act as a pack animal.
If a pen isn't large enough to sustain your animals, but it's still growing season, then consider planting dandelions inside the pen. Once the dandelions reach 10% growth, they are considered edible. This is less effective than growing haygrass outside of the pen, but can be used in a pinch.

Pen animal list

A complete list of the current pen animals. Animals not on this list can be designated to an allowed area and do not require a pen.

Name	Hunger rate^[1] (nutrition/day)	Products per day
Alpaca	0.44	4.5
Bison	0.86	8
Boomalope	0.86	11
Capybara	0.36
Caribou	0.44	5
Cassowary	0.45	0.3
Chicken	0.22	/ 1
Chinchilla	0.2
Cow	0.86	14
Deer	0.32
Donkey	0.52
Dromedary	0.86	9
Duck	0.28	/ 1
Elk	0.86	11
Emu	0.45	0.3
Gazelle	0.24
Goat	0.36	4
Goose	0.45	/ 0.5
Horse	0.68
Ibex	0.32
Muffalo	0.86	8
Ostrich	0.67	0.3
Pig	0.8
Sheep	0.36	4.5
Toxalope	0.86
Turkey	0.45	0.75
Wild boar	0.48
Yak	0.86	11