The Scottish SPCA was alerted after a motorist spotted the animals close to the Dalwhinnie exit.
One of the piglets was already dead but another was curled up at the side of the road, still alive.
The animal was taken to a vets where, tragically, it also passed away.
Animal Rescue Officer Beverley O’Lone said, “We believe these piglets may have fallen from the back of the vehicle or trailer they were being transported in.
“The vet advised it’s likely they both died as a result of injuries sustained when they fell onto the road.
“It’s possible the person driving the vehicle wasn’t aware they had lost the piglets but we believe other motorists may have witnessed this incident.
“Unfortunately the piglets don’t have any tags or other identification so we’re appealing to anyone with information to come forward.
“We’re very keen to trace the person who was transporting these piglets as we have concerns they were not secured appropriately.”
Anyone with information is being urged to contact the Scottish SPCA Animal Helpline on 03000 999 999.