1. Cut bread into 1/2-in. slices. Place slices in a large bowl and add milk. Mix gently with a spoon to saturate with milk and let stand about 30 minutes. Stir occasionally.
2. Meanwhile, place a 6- to 8-qt. pot over high heat. Squeeze sausages from casings into pot. Discard casings. Cook meat, stirring often to crumble, until lightly browned, 10 to 15 minutes; discard fat. Add parsley, garlic, onion, and celery. Cook, stirring often, until vegetables are lightly browned, 5 to 8 minutes. Add chard and 1/2 cup water and cook, stirring often, until wilted, about 5 minutes.
3. With your hands, squeeze bread slices to break them into tiny pieces. Add cooked meat mixture, parmesan, basil, sage, and rosemary. Season with salt to taste.
4. Preheat oven to 325° or 350° (use temperature turkey requires; see Note below). Spoon stuffing into a shallow 3-qt. (9- by 13-in.) casserole. For moist stuffing, cover with foil; for crusty stuffing, do not cover. Bake until hot (at least 150° in center) or lightly browned, at least 30 minutes.
Make ahead: Up to 1 day ahead, make stuffing, put in casserole, cover, and chill. Allow about 1 hour to bake.
Note: For turkeys 10-13 lbs., oven/bbq temperature should be 350°; for turkeys 14 lbs. and over, oven/bbq temperature should be 325°.
Note: Nutritional analysis is per 3/4-cup serving.