How to explain to how infirm a bird is?

i found a bird outside and i was wondering how to tell elderly it was
The best way to know the birds age and sex is to do a DNA analysis by a avian vet. The vet will also tell you the species of the bird and the food suitable for it.
There is no way to communicate how old a bird is once it has its adult plumage. If it's an escaped pet bird, and at hand is a band on its leg, SOMETIMES there is a 2-digit year number indicated when it was hatch, but that's as close you'll get to knowing its age.
Answers:    for that u can do dna tests it will cost around 25 dollars

There really is no means of access to tell.. Sorry
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