We're getting into the ol' Blade Runner/Alien combined universe topic again.
You will recall Animoid Row from Blade Runner, (and Do Androids Dream of Electric Sheep) where Deckard likes to browse the various android animals for sale. And if you've played Westwood's game Blade Runner, you might remember that McCoy, the Blade Runner in that story, has a replicant dog called... Maggie.
Personally, Ash as an android has always bothered me in one respect, which is that the tech that underlies his manufacture seems out of place with the rest of the tech, or I should say, low tech, that makes up the rest of the Nostromo; chunky knobs and dials and levers and steam valves and so on, whereas Ash is fluids and glass beads and limp spaghetti.
TC