Judging from these leaves, I would see if he feels any different, has strange behaviour or does not have an appetite. If those symptoms occur I would suggest taking him to a vets. Also ask online about what some different leaves look like.
Best regards,
Edd
It looks like a species of Hoya. When you break off a piece does it bleed white milk? If so, they are mildly toxic but some species of tortoise eat it in the wild, like RF and Manouria.