From 2speccers2tools wiki

At long last, the difficult process of domesticating the assbrains was finally tackled by the nanosophonts due to them realizing that they weren’t completely useless and could easily be capitalized on. The final result was the domestibrain, a new species of assbrain characterized by being extremely inbred and genetically modified to suit the needs of its creators. They can survive on their own in any moderate to hot climate with some presence of liquid water, and have thus survived on their own on 2s2tworld and the piss planet belt. They are bundled more densely than their ancestors, producing more spite per square inch but releasing far less of it into the surrounding area (the spite is usually separated by sophont-made means, preventing it from contaminating the ecosystem). Domestibrains have made the synthesis of pure spite items far easier for the nanosophonts, with the spite often being used to make food dishes and wildlife repellent.

Note that the habitat list only contains wild versions. There are indeed domestibrains being farmed on every planet where the nanosophonts live, but they must be contained in an enclosure with the correct temperature and humidity lest they die.