Katoro (the same word is used for singular and plural forms) are, in appearance, similar to Terran rabbits, according to stories related by spirits. However, katoro have never been observed to stop growing at any point in their natural life cycle (which is normally 10 years, if they're not killed prematurely). The largest katoro on record grew to 5 feet 5 inches tall (at the tip of the ears), and 7 feet 2 inches long, weighing 188 pounds, before dying at 13 years of age. This, however, is quite rare, as katoro have many natural predators, including humans, and no serious means of defense. Most livestock katoro are slaughtered around age 2 or 3, to use for meat and fur; those living in the wild may be killed by predators even younger than that. It is common for those not involved in raising katoro to wonder why they're not kept alive longer, to provide larger supplies of meat and fur. Quite simply, it is a question of the the expense of keeping them adequately fed; once they reach a certain size, the cost of feed would outweigh the value of production.
An interesting and unconventional use which was once found for katoro by Sorreters was the incorporation of the animal's natural continued growth into the development of several types of mythical creatures.