zebras will sit on the gouldian eggs-feed the young - and get them out flying BUT they don't appear to feed them for any lengthy period once they fly. first off you'll hear them begging for food as the parents have returned to do another nest. next up you pick them up off the floor!
I actually tried it 7 years back -total waste of time PLUS even if you are successful if those birds are not removed by 14 or so days they will no longer be gouldians
sure they might look like a gouldian BUT will be imprinted and act more like a zebra. you will have to get other fostered gouldian to get them to breed and you will find they will hang about more with zebra finches than their own kind
i'd go the other way and just -toss the eggs. I toss hundreds of eggs per year no big deal. no different than throwing out a chicken egg.
gouldians with canaries. biggest mistake in bird history. one bird the canary a genuine air sac mite carrier and the other not capable of going the distance with air sac mite. here in oz no breeder would run canaries with gouldians
I have nothing against canaries -I've had them myself but not housed with gouldians unless you run an $76 air sac mite preventive program. your birds may never get the ASM but like anything if they get it once and your not on the ball -curtains for them
keep an eye on your birds and take note of any gouldian or canary sitting on the perch gasping away. if so catch that bird and place it to your ear - if you hear a click click click sound .....air sac mite.
you will have to dose all birds immediately with S76 and treat them over several weeks. birds with a mild infection will pull through. if heavily infected good chance they will die. either way treated or not they will die so you have no choice
years back I purchased 20 gouldians which were house with princess parrots. I knew princess and gouldians don't mix as pricess parrots are huge worm carriers. so once home I placed them in breeding cabinets and dosed them with a worm cleaner call worm out!
first 24 hours all good, day after 7 dead day after that 6 dead day after 3 more dead and the other 4 survived. these were then sold back to a petshop. I knew that I should not have bought the birds in the first place. what happened was the birds were that full of worms -the wormkiller did the job and killed them but they blocked up the rear outlet to remove the problem and party over!
I was very fortunate I wasn't silly enough to let them go straight into various aviaries. those birds would have contaminated the floor with worm eggs and i'd had a real problem on my hands. at least I only had to disinfect the cabinets out
always remember - never let any outsider enter your aviary. you have no idea whats on their footwear or where they have been. that tip alone will help your birds live a much longer and happy life