A run-down on how it seems to work;
1) I've caught a rhino (two by now) in a cage trap.
2) it was listed in the z-menu as 'not tame' because it was not tame. (
)
3) I toggled 'train war' on it and told 'any trainer' would do.
4) I saw my animal trainer in the U-menu with ''Train Stray Rhinoceros (+Trained+) for War'
5) It is now listed as Stray Rhinoceros ♂ (+Trained+), then AW and unavailable in the z-screen. Second rhino is listed as 'not tame' and my animal trainer is currently working on it. Hovering over the TRAINED rhinoceros in the z-screen shows "Status: Skillfully Trained" rather than "Status: Domesticated" for Onol Gembishstinthad the bunny. Untrained rhinoceros shows no such status at all.
6) the first one had a traipse amongst my living quarters and is now pastured. Hopefully it shan't starve.
7) as the previously mentioned 'unavailable' indicates; it is NOT a work animal. Therefore, I can NOT assign it to a Dwarf like I would a war dog. Disregard, but not entirely.
8
) I thought the animal trainer was training the second rhino; this was not the case, it was training the first rhino again. It is still considered Skillfully Trained but also Work Animal (rather than
unavailable.)
9) The second rhino has reached the intermediate stage and "
the dwarves of The Dangerous Rim now know a few facts about rhinoceros training."
10)First rhino is also a 'Stray war Rhinoceros' rather than 'Stray Rhinoceros.'
I hope this may have helped somehow.