The Welsummer Thread!!!!

[littledel]

Quote:
Don't know if it is true, but I had someone tell me that the older a roo gets the more boys he throws. That younger roos throw more females. May just be an old wives tale. My dad had an older RIR roo and he threw about 70% males, but my young RIR threw about 70% females. Interesting, but don't know if it is true or not.

 

[EweSheep]

As far back as being a student in pre-vet days, they do say that the males are responsible for the sex of babies, including humans. Horses, cows, goats, sheep and dogs and cats are the ones I know they do determine the sex of babies. For chickens I would like to say yes but don't hold me to it lOL. Need alot of research on it to make it worthwhile. What I do know, we can not sex chicks like the gators and crocs would do temp wise...it just dont work.

 

[Lensters]

Quote:
Actually it is the hens that determine the sex. Birds are the opposite of mammals in that respect.

Mammals: male XY females XX
Birds: male ZZ females ZW

Here is a link for more info: http://www.nature.com/embor/journal/v2/n3/full/embor459.html

However, like mammals the hens produce a 50/50 split of cockerel/pullet eggs. It is a result of mieosis: http://en.wikipedia.org/wiki/Meiosis

As for getting more cockerels than pullets, what is your hatch percentage? There is a theory that cockerel embryos survive temperature spikes better than pullet embryos. So if your losing a lot of partially formed embryos that might be your problem.

 

[HathawayHens]

The female chicken determines the sex of the baby. Weird, but true.

The chromosomes are ZW.

 

[josh44]

I think it is the roosters that control the sex of the chicks,
I use to have a rooster that produced nothing but cockerels, Every single chick that hatched was a rooster.
So I got rid of him, and kept a son of his, he's a much better breeder, I get about 50% roos/50% pullets now.

 

[flower]

In humans the timing of copulation is one of the determining factors. The later in the ovulatory fertile cycle = male.

 

[Lensters]

Quote:
Not that this has anything to do with chickens, but I have heard that too. Is it still just a theory or has there been some research to substantiate this? The suppositions I have heard range from sperm motility, uterine chemical balance, to egg penetrability.

 

[Goose and Fig]

Hmm- well my roos are both less than a year old- so I don't think it's age. I'll take the dominant guy out before I do any mroe hatching. My hatch results were the same if I used an incubator or a broody- but I can see how a temp spike could effect things. Thanks everyone- very interesting stuff!

 

[Lensters]

I'm open to credible theories on how the rooster plays into the determination of the chick's sex. My problem is that meiosis can occur in the female bird's gonads before the rooster even mates with her. It isn't like in mammals where the sperm is selected by the arduous journey to the egg allowing for many variables to affect which one wins the race.

Now the roo that fathered the hens could have an impact on the ratio of cockerels to pullets. If you read the first paper I referenced you will see that both the Z and W genes are composed of multiple alleles so it is possible to create a hen that will consistently produce only male offspring.

There is also the case in a select few chickens where meiosis fails to occur and the hens produce fertile eggs without the need for sperm. These offspring are clones of their mother. This line of chickens are very rare and as far as I know they only exist in the research flock here at OSU. The only reason I know about these hens is that I took my genetics class from one of the two world renown chicken geneticists here at OSU.

How is the sex of the offspring being determined? If you are using the chick's down markings then the problem is probably there. I have recently come to find out that I have a few hens from a line where the eye markings in the down are not sex linked. I thought that I was just getting lucky with a 60% ratio of pullets but in actuality it is the genetics of the hens where the markings are not sex linked. The lack or abundance of these markings could be from the rooster or the hen. If the ratio is extreme it would be the rooster. A smaller ratio would indicate a hen or two.

 

[rsquared]

Quote:
Pinkchick, How old is your boy?