Deer

A deer is a quadrupedal animal native to Earth. They usually inhabit forests, and are herbivores.

In 1957, when a team of Vulcans crash-landed on Earth, their scanners detected two life signs approaching, and thought they were Humans. They were in fact deer, to which T'Mir commented "Fascinating." As they hadn't eaten in several days, Mestral considered capturing one and eating it, as it could sustain them for several days. However, Stron was disgusted at the thought of eating meat. 

A deer appeared in Commander Chakotay's akoonah-induced dreams. He was hunting the deer through USS Voyager's corridors with a spear. In the ship's mess hall, the deer morphed into a member of the dream species.