Can dogs have blackberries?
Yes – blackberries are generally safe for dogs when plain and fed in small handful-sized portions.
Why it is or is not safe
Most berries are not considered toxic. Too many can cause loose stool because of fiber and natural sugar.
How to serve
Serve washed, plain berries. Start with 1-2 berries for small dogs or a small handful for large dogs. Avoid sweetened or chocolate-covered berries.
Symptoms to watch for
Sources: See full veterinary references here