In a large skillet, saute the mushrooms, celery, onions and parsley in butter until the vegetables are tender. In a large bowl, toss the bread cubes with salt, sage, poultry seasoning, thyme and pepper. Add the mushroom mixture. Combine eggs and broth; add to the bread mixture and toss. , Transfer to 5-qt. slow cooker. Cover and cook on low for 4-5 hours or until a thermometer reads 160°.