Food safety
Can dogs eat oranges & citrus?
Yes, but be careful
A small piece of peeled orange won't hurt, though most dogs aren't keen. Skip the peel, pith and pips.
Being honest about this
Dogs differ, and amount matters — a crumb of something rich is not the same as half a packet. Treats of any kind should stay under a tenth of what your dog eats in a day. If you're unsure, your vet would far rather take the call.