Pumpkin seeds might be a preventative, but not a treatment. I recommend using Valbazen (albendazole), it's a liquid cattle/sheep wormer and can be purchased from jeffers livestock.com
Dosage is 1/2cc given orally to standard size chickens...1/4cc for smaller chickens. Discard eggs for 14 days. Retreat again in 14 days.
Hi I found this from a thread search..hope this helps good luck!