cockatiel egg laying

Question
Hi again Chrys,
They are incubating the eggs now, well at day time they do but at night they dont. They sleep outside the nest at night.
I have noticed something odd. Today i have seen the pair mate. I heard that a pair wont mate if they are in the process of incubating.
I also candled the chicken egg. The cockatiel egg appears exactly like the candled chicken egg. It has no viens at all. its been 7 days now and still one egg. I dont really know their age. Is there any possible way to find out their age? Both of them are over 9 months for sure because when i got them they had full colour so they already went through their first molt(5 months). Its been 4 months since i got them which totals up to 9.
I also forgot to tell you that the female is having diarrhea sisnce the day she laid her first egg. One more thing i had to tell you before. The egg has some poop on it. The nest is purely clean and has clean pine shaving. How did the poop get on the egg?  
Should i take the nest out?i am getting worried...the female might get egg binded  
Thanks, I am not sure if you are a vet. If you are not i consider an avian vet. Your info has helped me tremendously
thanks again,
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
hi Chrys,
I am not sure what their age is. The breeder i got these from said they are old enough to breed.
Its been 6 days now. The egg looks pinkish with a white circle at the bottom. I candled the egg for the first time and i saw nothing. i looked carefully and didnt see any viens or anything like that,not even the embryo. How does an infertile egg look from the inside?
i am seeing the pair eat massive amount of cuttle bone. I have a feeling that they are infertile.
-------------------------------------------
The text above is a follow-up to ...

-----Question-----
Yes, she does have mate. I havent seen the male feeding the female but i have seen them mating. they spend time in the nest together and communicate the "bonded way"(comunicating from inside the nest to outside or from outside to inside). I put in the nest box long time ago(about 3 weeks ago) and on nov 5 the first egg was layed. Till now there is no sign of the second egg. They are not incubating the egg very well, i think its due to the fact that they incubate after the cluth is layed. I am sure that one is a male and one is a female.

What should i do if its an infertile egg?

-------------------------------------------
The text above is a follow-up to ...

-----Question-----
Hi Chrys
my cockatiel has layed an egg. I am not sure if its for the first time. From what i have researched it said that cocaktiel should lay an egg every other day until the cluth is layed. The first egg my cocaktiel layed was 4 days ago. There is only one egg. why isnt she laying more? i give her veges and provided her with a cuttle bone and a mineral block. but still. why is this happening?
thank you for your help.
zuhair
-----Answer-----
Hi, Zuhair.  Thanks for posting!

Normally, tiels lay an egg every other day until a full clutch of about 6 eggs are laid (6 eggs is the norm).  Some birds only lay 2 eggs, some lay 4 eggs, some lay 7 eggs, etc.  Perhaps your bird is only going to lay 1 egg.  This would be unusual, but not unheard of.  I do not know the reason your bird has only laid 1 egg so far.  Obviously, her body hasn't produced another embryo for an egg to form around and be laid.

Giving a bird veggies, a cuttlebone, and mineral block doesn't really have anything to do with the number of eggs your bird will lay.  These things help to keep her healthy when she is laying eggs, and will also help her have healthy youngsters if/when viable eggs are laid.

Does this bird have a mate?  If not, then she is laying infertile eggs.  If she does have a mate, do they have a nesting box?  Are they pair-bonded (does the male feed the female beak-to-beak)?  

Come back with answers to my questions and any other details you can provide, and I can likely help you better.

Thanks.

Chrys
-----Answer-----
Hi again, Zuhair.

I forgot to ask you how old these tiels are?  If these tiels are young and/or this is their first clutch of eggs, they may not lay a full clutch of 6.  However, It's not common for only 1 egg to be laid!  More may come or she might start laying after a short break...this happens sometimes.  They normally don't start incubating their eggs until the second egg is laid (she'll continue to lay eggs after she starts incubating the first ones), so it doesn't surprise me they aren't incubating yet.  If they have mated, the egg could be fertile.  Just leave the egg where it has been laid and see what happens.  

Keep me posted as to what is going on, and I'll try to help as things develop (or not).

chrys

-----Answer-----
Hi again, Zuhair.

Don't give up!  These birds might just be young, maybe too young yet.  Tiels should be 18-24 months old before breeding because they aren't physically mature until then.  People breed them younger, but they shouldn't...shortens their lifespan.  

There's several reasons why this could be happening...you just need to give it some time.  The fact that they are eating a lot of cuttlebone is a good sign!  Candle a chicken egg from your refrigerator (or one you've purchased from the grocery store)...this should be an infertile egg.  An infertile tiel egg will look the same, but a tiel egg should be 7-10 days old before you try to candle it.  Also, you won't see anything anyway if the female hasn't started incubating the egg.  When an egg is laid, it's either fertile or it isn't (it's fertilized inside the female).  When the female incubates her eggs, the fertile ones will develop on the inside and eventually hatch...the infertile ones won't.  A fertile egg will have a small dark spot inside and you'll see little red veins.  As the fertile egg grows older, you'll see more veins, the dark spot will get bigger and bigger, etc.

Give it some more time and see what happens.  Is there a reason you need to rush into this?

Chrys

Answer
I think they have basically abandoned this egg.  Also, if they are only 9 months old, they are TOO YOUNG to be breeding.  They should be 18-24 months old before being bred.  This is most likely the reason for these problems.  Give them a chance to grow up first...they haven't matured inside yet.  What kind of nesting box are you using (how big and is it a cockatiel nesting box)?   

I am not a bird vet.  I have over 17 years experience breeding/raising about 15 different species of parrots.  

I also keep racing pigeons.  I offer my many years of experience and knowledge to anyone who needs it on this website.

It still may be too early to see anything inside the egg.  Let them incubate it another 2-3 days, then candle it again.  If it looks the same, remove it from the nest and destroy it.  If the pair is mating, they are likely getting ready to lay more eggs.  I recommend you take the nesting box down and let them get older before trying to breed them/allowing them to breed.  You may continue to have problems like this if you don't.  And losing babies when they hatch is not acceptable if it would be the result of allowing the parents to breed when they are too young.

Poop can get on eggs from the parents feet or from some poo being on them somewhere and transfer to the egg.  You should not be putting anything like pine shavings inside the nesting box.  Cockatiels don't want anything in their nest box.  This could be another reason they don't want to incubate this egg.

Maybe you need to share with me the setup you have your tiels in, such as what is the cage size, how do you have the nesting box setup/attached, any other birds around, etc.?  There might be some other things you can change that would help.  However, your birds are still too young to breed right now.

Chrys