I work at a farm supply store and the hatchery sent us a shipment of about 25 ducklings and once I unloaded them into the coop I noticed one kept toppling over and couldn’t walk so I took that one and another home to take care of it and help it heal and I tried putting it in a sock overnight I’ve done niacin and electrolytes and vitamins for about 5 days I ordered brewers yeast to add to the food and he just doesn’t seem to be getting and better he eats and drinks by himself when her rolls himself over to the feeder and water but he just seems exhausted and now he’s constantly flicking his head and clear liquid is coming out of his nose. The other duckling is doing great and is now twice the size of the sick one how to I help him.