Cloaca and hardboiled eggs for a snack
October 1st, 2007 by The Bosphorus
The Missus was cracking a hardboiled egg for the kids. Spotz said he couldn’t believe that some dinosaurs ate other dinosaurs eggs. So I told him that weasles and snakes ate egg yolks, too. Then the Missus pointed out the obvious that we’re nest robbers, too. I said yeah these eggs would’ve become little chicks if we hadn’t grabbed them first.
The Missus then raised a very important question. Are those chicken eggs fertilized? I said yeah, sure. I mean how else would they get fertilized if they weren’t before they hit the nest?
Well as it turns out they just may not be. Check this page out for more info, but here’s the gist:
Birds, like mammals, use internal fertilization. Many species of birds lack a penis; instead, the male just has a genital opening (cloaca), which must be positioned against the female’s genital opening (also called a cloaca) for sperm transfer. Male chickens, however, do have a small penis to facilitate mating. In any case, after copulation, which only lasts a few seconds, the sperm quickly swim up the oviduct toward the ovary. The sperm can stay alive in the oviduct for several weeks, ready to fertilize the next egg cell (oocyte) that appears.
Oocytes are produced in the ovary, packaged with yolk within a thin protein membrane, and released one at a time into the funnel-like infundibulum of the oviduct. The oviduct is a tubular passageway leading from the ovary to the outside world. It is also an assembly line in which the various layers of the egg are constructed. After an oocyte-yolk package is released into the infundibulum, it lingers there for about 20 minutes. If sperm are present, then the oocyte is fertilized and becomes an embryo. But if no sperm are around (that is, if the hen has not mated), then the egg still proceeds down the assembly line of the oviduct. In this assembly line, albumen (egg white) is added around the yolk, shell membranes are added, and the shell itself is constructed. Finally, the complete egg is pushed through the vagina and out the cloaca.
If the egg has been fertilized, then the embryo inside has already divided several times but remains a group of unspecialized cells. When the egg is incubated at about 37 to 38 °C, the embryonic cells differentiate to form a chick, which will hatch after 21 days. If the egg has not been fertilized, then the oocyte within will never grow or divide, and the egg will never hatch. The eggs you buy at the supermarket are eggs that have never been fertilized.
Who knew?
October 1st, 2007 at 3:11 pm
I did!
October 1st, 2007 at 3:15 pm
I must be coming down with that virus. I’m feeling sick.
October 1st, 2007 at 3:38 pm
You would, AT.
October 1st, 2007 at 3:43 pm
Believe me, if you get an egg that has been fertilized - you know!
It does happen on occasion, but more from local farms than from supermarkets.
October 1st, 2007 at 4:22 pm
Egg farmers know, that is why they sell the roosters for the chicken isle at your local grocery store. I like fried chicken. Tastes like turtle.
October 1st, 2007 at 4:23 pm
I’m a small town girl and we often would buy our eggs from a local farm. Imagine my surprise when one day, I cracked open an egg that was not only fertilized but the chick inside was nearly perfectly formed. It was dead. And it was in my bowl. To this day I cringe when I crack open eggs. And, I won’t buy eggs from farms anymore. For some reason, my mind has tricked itself into thinking that that wouldn’t happen with grocery store eggs.
October 1st, 2007 at 4:44 pm
I knew, but that’s just because I was raised on a chicken farm. We did have 2 roosters that were suppose to grow up to be chickens. We didn’t kill them once we found that they didn’t conform like they should have. We never did get any eggs with chicks inside though. I wonder if it was because we collected eggs every other day? Not sure.
October 1st, 2007 at 4:58 pm
Yeah, I’m not surprised either, but we’ve been raising canaries on and off for decades. We’ve got three hens sitting on unfertilized eggs now (we had three clutches hatch last year, so we have quite enough canaries for now, thank you). Egg laying depends on light-dark cycle and nutritional state of the hen.
October 1st, 2007 at 5:39 pm
I don’t buy eggs at all. I collect them from my three little hens… and there’s not a rooster for miles around.
Chickens make good pets. Just like canaries, except I don’t have to keep them in the house.
October 1st, 2007 at 5:43 pm
I’ll bet they don’t sing as well as canaries, though I’ll grant you that chicken eggs are larger.
BTW, you don’t have to keep canaries in the house, either. The first hen we got, back in North Carolina where we went to grad school, was from a breeder who kept his flock in a shed in the back yard. He had a wire mesh running from the ground to the edge of the roof, so the birds could either fly around the outside of the shed or in through the window to the inside. He heated it in the winter just enough to keep the drinking water from freezing.
October 1st, 2007 at 6:16 pm
Hells bells.
Who knew the Tumor readership included a bunch of chicken farmers?
Wonders may never cease.
October 1st, 2007 at 6:30 pm
I’m going to start a band and name it Cloaca.
October 1st, 2007 at 8:33 pm
Been done, Eaves:
http://en.wikipedia.org/wiki/CMX_(band)
October 1st, 2007 at 10:21 pm
So I’m the only one who’s going to make a snarky comment about copulation lasting a few seconds then??
October 2nd, 2007 at 9:11 am
Mmm… fetus for breakfast. Speaking of cloaca, you know that EVERYTHING comes out of ONE hole on a chicken. They clean ‘em up real nice for you at the grocery store. Add me to the list of chicken farmers. We have 12.
October 2nd, 2007 at 11:58 am
“So I’m the only one who’s going to make a snarky comment about copulation lasting a few seconds then??’
Nobody else appears to have that problem.
October 2nd, 2007 at 1:53 pm
Ha ha!!
October 2nd, 2007 at 3:02 pm
Gotta get going before the three second rule comes into play.
October 4th, 2007 at 7:37 am
I knew, I knew! We have 3 chickens after my sons school hatched eggs from a local farm, you would be surprised how many people think that you have to have a rooster to get hens to lay eggs, my neighbour wont believe me and says I wont get eggs with my 3 hens! You could eat a fertilised egg soon after it has been laid and never know it, its just a few more cells.