Oh they do love those 'found' fishy flavored treats don't they?
While the crab meat itself isn't likely an issue the shells may be.
Fresh water crayfish do carry parasites but the ocean ones don't appear to have ones that impact dogs.
Two concerns would be digestive upset from the roughness of the shells or possible obstruction from shells getting stuck along the digestive tract and not moving on through.
Long dead crabs can also be a source of bacteria infection and digestive upset.
As she gets older its more likely she would have digestive issues from ingesting these. What her system can handle at this age may be a problem later one.
Hope this helps you!
Dog Expert:Rescue, Train,Breed,Care
30+ yrs dog home vet care & nursing, rescue, behavior&training, responsible show breeding, genetics