My two middle dogs were raised around chickens and I have no problem with drive. Believe it or not they learn the difference between the yard and field. Now if they happen across a chicken in the field I may be in trouble.
They are smarter than you think.
I also raise game birds and they run right past the pens. Take them to the field to run upland and its game on.
Like said earlier this issue may be with grandma and what she does if pup messes with her pets.