vuk dlaku mijenja, ali ćud nikada
Serbo-Croatian
Etymology
Literally, “the wolf changes his hair, but never the character”. Cf. Italian il lupo perde il pelo ma non il vizio, English the wolf may lose his teeth but never his nature, Dutch een vos verliest wel zijn haren, maar niet zijn streken.
Proverb
vuk dlaku mijenja, ali ćud nikada
- a leopard cannot change its spots (one cannot change one's own nature)