I have not used Clavamox as that is obtainable only by vet. Enrofloxacin can be gotten from pigeon suppliers, the oral form. Injectable is vet only. I have used the oral form and the injectable of that. With the injectable there is issue of tissue necrosis at the injection site, so you have to move the spot around (on the breast). This is one link to the oral form:
https://jedds.com/products/enrofloxacin-10?variant=40215712661693
Doses I have used are:
10mg/kg of body weight, twice a day for 5 days
15 mg/kg once a day for 5 days
20 mg/kg once a day for 5 days
Depending on what I'm treating I will often start with the higher dose and adjust it down if I see droppings looking sick after giving it, until droppings become more normal. But for your young bird you may want to try the lower dose. It is harder on them than amoxicillin which is usually well tolerated.
If you can find Clavamox I'm sure someone here can help with dosing that. There are members here who do have the benefit of veterinary help.
Amoxicillin dose is 57 mg/pound of body weight twice a day for 5 days.
