I am also Orthodox, and Israeli/American.
I havent paid any attention to here in the states other then our own home, but the removal of leven is from the HOUSE, not the whole property, farmers in Israel observe all of the Hagim, their livestock dont, and its a violation of Torah to be cruel to your livestock, and changing their diet to disrupt their digestive systems is cruel. Cows are fed their regular rations 24/7, and milked on Hagim, the same as any other day, to not do so is cruel also.
Buy the proper diet for your poults and feed them that as they need it. Our livestock are depending on us for proper care, if you cant provide it give them to someone who will, at least then you will get some mitzvot for it.
Simply doNOT bring their food into your house.
I cant believe you havent talked to your posek on this.
When you go to Eretz visit some poultry farms.
Yaacov bin Yaacov Levi
Itamar, ha Shomron