The rules are identical for bringing eggs or chicks in: they must be accompanied by a vet health certificate. Typically it's between 80 and 200 dollars depending on what the vet charges. If you are already NPIP the vet can use that certification on the health certificate. That certificate must be with the products when it crosses the border between Canada and the US.
It is irrelevant if you hand carry them. The process is the chicks or eggs are typically shipped to a post office at a border crossing --a customs office, like at Sweetgrass Montana, There is apost office that there that accepts the eggs/live chicks. As the Canadian receiving them, you go to the post office, pick them up onthe US side and then declare them when you go back through customs and into Canada.
There are basically zero airlines that will fly chicks or eggs directly to a Canadian city. I understand a few do it but you really have to have someone on the 'inside' to do all the paperwork for you. If you were to just call the airlines they would tell you they don't do it.
There are lots of us who have brought in chicks from US breeders and hatcheries in the method described using the post office.
I could also drive into the US and pick up the chicks with the papers and bring them back. But I must have the health certificate. Otherwise it's illegal.