Stuffing or preserving was a means of maintaining a dead animal's corpse for display purposes.
Trelane kept several preserved creatures in his house, including several preserved creatures, including a salt vampire and the mounted head of an alligator and an Alfa 177 canine. (TOS: "The Squire of Gothos")
Neelix hung a stuffed Furfly in the engine room of Baxial in 2369. (VOY: "Timeless")