Drops are a great way to underdose. Best not to do it.
The "minimum" effective pour-on dose is 0.5mg/kg
1 / 2.2 x 0.5 / 5 = ~0.045 ml per pound.
The dose I would use is 1 mg/kg
1 / 2.2 x 1 / 5 = ~0.045 ml per pound.
I would give the following:
4.5 pound duck
4.5 / 2.2 x 1 / 5 = 0.4 ml
6...