As per "Feeding birds" web page plus the details below.
Seeds for parrots :( including Australian and Non-Australian parrots, the Conure, Cockatoo, macaw and Rosella )
Commercial seed mixes have a fairly standard mix of seeds and require a balance of fruit and vegetable to give the birds a suitable nutritious food intake to keep them in good condition for the tasks of maintaining their own health as well as breeding and raising their young. One problem that many breeders come across is birds not eating a balance of seed and other nutrients. Birds generally accept foods that they have been fed to them by their parents. Encouraging some birds on to new foods can be a frustrating task and some birds win the battle and refuse to eat any foods other than their favourites.
The domestication of all our aviary
birds, including cockatoos, has led to a change in the foods the
original captive birds ate. We give seeds and other foods to our
own pairs of birds and the ones that accept those foods will often be
the most productive breeders. The more generations we breed with
an aviary mix of foods, the ensuing generations will adapt to those
foods. In the wild cockatoos cover vast areas of country and
follow the supply of suitable foods. The variety of foods and
insects the wild birds have access to is impossible to duplicate in the
aviary or captive breeding situation. The time and resources
breeders have available is often restricted by the ever increasing
demands placed on their lives by pressures other than the needs of the
birds. People living in rural or farmland areas may have access to
a wider range of natural foods. City people often have a wider
range of frozen foods, plus fruits and vegetables that have been
freighted in from interstate and available all year round.