hi there we have 2 female ducks?

one duck has had its feathers receiding on its neck and the wing feathers have gone leaving finger like things where the feathers once were . we initially thought it may have been bird lice and we have treated them with proper treatment as directed. where as the other duck has not really produced any symptoms like the other could you possibly give us any ideas on what maybe causing this ????

there are common duck diseases that cause this,have a look here. www.dpi.nsw.gov.au/agriculture/livestock/poultry/health-disease/duck-disease – 9k

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