Dio is, happily, well aquainted with the train's obsession with bringing actual livestock onto an overcrowded train with minimal real facilities, so the fact that the tigress has one such pet earns a glance to determine if it might be a threat (surely not) and then decide its coloration likely means it's poisonous.

"The same size as other cars, but to not be cruel to the inhabitants of it, it would be best to maintain the smaller species." He ticks off on his claws, thoughtful. "Cubans of course, clever creatures. Some ghairals, dwarf caimans.." He pauses, wriggling his fingers for a moment. "..Others I don't know of yet.."

Well he'll find out by them. "Though you may not want to present them a 'friend' that is food sized."