I have  a litter of 6 age 6 weeks, medium/large breed. I am feeding Purina Pro Plan which I have used for a long time now. Never had this before where the pups are eating their own poo. Obviously clean it as soon as I see it but I have caught the several times now. They are house reared so cleaned out many times a day. Mum still sometimes does this, do you think it is because they are copying her.

Yes, they are doing as mum does, try to get their first and pick up more often.

ive had 2 litters do this and pups out of this litter have been very forward dogs lol but it dont help when people come to see their pups and they poo and all fight to get to it before you can lol