Can one leave the country if on probation for a misdemeaner?

Most likely not, usually you can't even leave the state... so ask the probation officer.

You must have prior written permission from your PO to leave the state or the country. If I were you, I wouldn't leave either until your probation is over. You will just be asking for more trouble than you can handle if you leave the state or country even with the PO's approval. If you get into any kind of trouble in say a different state or different country, you will automatically violate your probation. You might be better off just staying home and waiting until your probation is over.