Warhammer 40,000: Rogue Trader (1987), p202 — Zoats

Zoats are the most common of all the Tyranid's many specially engineered slave races. Other slave races are little more than animals, mere blobs of protoplasm dedicated to cleaning and maintaining the Hive Fleets of which they are a part. Even the hulking spacecraft that compose the Hive Fleets are in a sense races as they are grown and nurtured from a common, albeit much modified, biological stock. Spacecraft are mindless monstrosities and the vast majority of other slave races are so dedicated to a single purpose it would be inappropriate to think of them as creatures. Zoats, on the other hand, are completely independent living creatures much like their masters.

The Xenobiologers of the Administratum believe that Zoats were created purely for combat. Tyranids, being creatures from space, suffer discomfort if they spend too long on a planet. Zoats, however, are stocky animals that feel quite at home in a wide variety of atmospheric and gravitational conditions. Like Tyranids, Zoats are centauroid. Their two rear sets of limbs are heavily built and muscular providing the creature with its means of locomotion. The front limbs are manipulative organs of great strength and are used to wield a variety of weapons. Unlike Tyranids, Zoats will eat anything although they largely subsist on a daily diet of three reconstituted protein based woven biscuits called Zoatibix. Zoats are common Hive-Fleet inhabitants, often equalling the number of Tyranids themselves.

Although they are a slave race, Zoats occupy important positions throughout the Hive Fleets and individual Zoats can gain great power. Rebellion from Tyranid control is not unknown, but is extremely rare. This is because Tyranids secrete a special slave-hormone which supresses the Zoats' natural sense of independence. However, renegade Zoats do exist throughout the universe, where they have broken away from the Hive Fleets or have become lost during scouting or exploration missions. Without the inhibiting influence of the Tyranid slave-hormone, Zoats are able to develop strong psychic powers. The path of independent Zoat civilisation is incredibly diverse, with small groups isolated from each other on widely scattered planets.