crop milk

Question
My husband has raised budgies for over 50 years, and I also do some minor breeding.
We had a conversation this morning after readiang a National Geographic article on birds.

Questions:
1)  Do budgies have "crop milk"
2)  Whatever the food is, has "crop milk" in budgies ever been analyzed for nutritional value.

Thank you,

Linda

Answer
Only pigeons have crop milk, but some budgie breeders call the regurgitated and semi-digested food that parents feed the young crop milk, but that's not strictly true. But the substance is produced in the crop and consists of some partially digested seeds and other food along with some cells from the lining of the crop. These no doubt contain some enzymes for digestion as well as some antibodies that will protect against some diseases. I would have to do some research on the nutritional value of crop milk as the information is not easily accessed, but the nutrition would vary a lot depending on what the parents have been fed.