When i was given my female maccy I was told she only eats day old chooks. And for the last few years that is all she has eaten, although I've tried her on other things and she has refused. Last week she took a rat for the first time. Must have been really hungry (all that mating, I guess). I hope she continues with the rats, 'coz they're easier to get than chicks.
Incidentally, found a trio of zebra finches in my aviary last year, dead and very slimy, lying side by side on a branch. After thinking about it, I came to the conclusion that they had probably been eaten by one of the Green Tree Snakes I had seen the week before, and when the snake found it was too fat to get back out through the mesh, it regurgitated the finches.
Hix