Do you really consider Chickens to be a part of the true definition of "Aviculture"

[SunkissedChicks]

aviculture, raising and care of wild birds in captivity, for the breeding of game stock, the perpetuation of declining species, or for display and education. The simulation of natural conditions is a necessary goal of aviculturists, allowing them to study aspects of mating and breeding behaviour that may not be easily observed in the wild. As a result of such study, a number of species, rare or endangered in the wild, have been kept from extinction by captive breeding. Some, such as the néné, or Hawaiian goose (Branta sandvicensis), and thewhooping crane
Britannica.

How does chickens get mixed into the definition if people are raising chickens for eggs and meat?

 

[Nsampsel]

When someone is breeding rare breeds to preserve the breed or improve the quality then it fits the bill. Also, anyone who breeds their chickens to sell hatching eggs or let their broodies hatch them would fit under "educational" or breed conservation as well. I mean, where would we be food-wise if someone didn't preserve the chicken species

Plus some people like to show off their pretty chickens. That fits the "display" aspect.