I can see that being an issue in large production. Pumpkin growing for us has always been a curiosity. We don't can or eat them, but kids are always fascinated by a pumpkin patch. We don't use pesticides in the garden; the only thing the pumpkin patch got was whatever came out of the coop every day plus whatever they left behind while lounging under the canopy of leaves.I know I’m in the minority, but I don’t give pumpkins to our poultry. I actually give the guineas almost no produce, as I didn’t want to teach them to raid our gardens. The guineas will steal blueberries off the bushes, but eat almost no other of our fruits and veggies. Lest you think they are deprived, we planted a small field of winter wheat and turnips that they love, plus plenty of clover (see pic). They are enthusiastic grazers.
As for the chickens, I keep thinking of our nearby pumpkin farm that I took our kids to years ago. I told the farm owner that I wanted to buy her pumpkins to make a pie, and she stated that they use so many pesticides on their ornamental pumpkins that she wasn’t comfortable selling it to me to eat. That mirrored my own experience trying to grow pumpkins, because we can make them look great for awhile, but squash pests always show up eventually and give them a disease that rapidly kills the vines. Pumpkins are slow growing, so it would take a lot of pesticide (or row covers, I want to try that!) to keep it going long enough to get big pumpkins in our area. Anyway, while we give lots of leftover produce to our chickens, I don’t give them pumpkins due to presumed heavy pesticide use of the typical pumpkins left over from Halloween.
(the 2 reg size pumpkins were store bought)