There are several different worming schedules out there and it will also depend on your personal situation. Where you live, exposure, how you house your birds, etc
We live in a area where it has its fair share of parasites.
We rotate wormers panacur, levamisole, valbazen, and ivermectin.
We worm 3 times a year with a closed flock. If we buy any new peafowl they get a fecal run on the droppings and wormed with panacur. Sometimes run another fecal if they had worms with first exam. This is cheap for me to do and best to know what you have instead of guessing. Can also find coccidiosis in a fecal along with fungal spores.
We worm 4 times a year if there is risk of exposure.
Most people don't worm 4 times a year, or even 3 as we usually do.
But in the beginning we had a couple of disasters with peafowl and I have not easily forgotten it.
Most dangerous and common fast killer of peafowl is cecal and capillary worm. Be sure you use a wormer in your schedule that kills these worms. Panacur (safeguard), valbazen, levamisole does kill them.