When the ducks are born- do I need to mix anything with their duck starter at any point?
You can add brewers yeast/nutritional yeast to their feed as a precautionary measure to ensure leg problems from occurring, 1.5 tablespoons per cup of feed, I would highly recommend this with heavyweight breeds. I like to add some poultry vitamins to their waterer for the first few days after hatch to give them a little "boost' as well.