Ok, so i actually meant that ability to process pain into an emotion and therefore feel suffering.
Punch a baby then ask if it they remember it when they are older and it can't as it didn't have the ability of thought as it's brain isn't developed enough (lol we're discussing punching babys
) so you could argue that it can't comprehend suffering just give a pre programmed reaction. If a human baby with a massivly larger brain doesn't have the ability to think in this way and be aware of what is happening then a baby bird surely can't.
Besides they wouldn't have felt pain from asphixiation and their brains are so small and aren't developed i doubt the birds were aware of any suffering