Gazelle

Gazelles were a type of Earth mammal the Third Doctor and the Brigadier once encountered at a zoo. This was early in the Third Doctor's life. Normally docile, the gazelle was attacking its handlers. This odd behaviour made the Doctor and the UNIT team suspicious of nearby activities. (COMIC: The Arkwood Experiments)

The Seventh Doctor and Ace saw gazelles living in the Ngorogoro Crater in 1926. (PROSE: Prelude Birthright) Gazelles were among the animals on board the Ark. (PROSE: The Ark)