Rose comb = fertility problems?

[Tam'ra of Rainbow Vortex]

So I was reading up on the breeds I have (one can never learn too much, I think) and while reading up on BLRW, it said that you should leave single-combed birds in your flock because the rose comb is linked to low fertility.
Well, since more than half my flock are rose-combed wyandottes I am a little concerned!
In all honesty, the rose comb is my least favorite aspect of the wyandottes, I do prefer the single comb. That is the primary reason I want to let them mix with the rocks...
So I suppose I should get to the point.
Has anyone observed this low fertility in connection to rose combs? And does anyone have any advice for a total novice hoping to get rid of both eventually? I mean, aside from the obvious keeping of single-combed birds.
I don't care about showing, I just want to keep pretty and useful chickens who can raise their own young effectively.

 

[azelgin]

I have a rose combed GLW in with 22 girls and he manages to give them a fertility rate of about 85%, based on the eggs I've incubated from them. I'd say he's doing OK.

 

[Krys109uk]

The pleiotropic effects of homozygous rose comb are well documented. Lower mating frequency, shorter duration of fertility after mating & inferior mobility of sperm after storage.

If one introduces single combs into ones rose comb breed & finish up breeding two heterozygous R/r+ birds you will have in the region of 25% wastage from single comb birds alone before even thinking about any other problems. Doesn't sound like a good plan.

It seems to make more sense to put fewer hens in with the males & set eggs more frequently.

 

[Smoky73]

I would prefer rosecombs in my Rhode Island reds for freezing issues int eh winter, however I only seem to have single comb pullets so far so am planning on keeping a Rose Comb Rooster.

 

[Kev]

The fertility issue is ONLY with the roosters "pure"(homozygous) for rose comb. Roosters with only one rose comb gene do not have fertility problems. Hens with rose combs have zero problems with fertility, even if they are pure for it.

As Krys mentioned, it has to do with sperm from roosters pure for rose comb having problems with shorter lives, and IIRC, higher % of deformed sperm too, not sure if that's right..

A rose combed roo with just one copy of the rose comb will have perfectly normal fertility and will be able to breed 22 girls with normal fertility. Likewise, a single combed roo will produce normal fertility with a flock of hens pure for rose comb.

Pure rose combed roos do better either single mated or trio mated(common practice with show stock/show breeders).. especially if he is one of those roos that highly favor only a few hens out of a flock- otherwise the fertility problem will become very apparent.

 

[Kanchii]

My d'Anvers had the worst fertility ever. Of the 8 months I tried hatching stuff out of my trio, I got one egg to hatch. And not for the rooster lack of trying, those girls constantly had bald spots, he bred them each about every 30 minutes!

 

[Krys109uk]

My d'Anvers had the worst fertility ever. Of the 8 months I tried hatching stuff out of my trio, I got one egg to hatch. And not for the rooster lack of trying, those girls constantly had bald spots, he bred them each about every 30 minutes!

To me, this doesn't sound like the problem is caused by the rose comb.​

 

[Kanchii]

Quote:
To me, this doesn't sound like the problem is caused by the rose comb.

you're probably right, they were just the only breeding group i've had to ever have this issue, and they were the only rose combed group i've ever had.

 

[The Yakima Kid]

Walnut combs and Rose combs both can lead to reduced fertility. Interestingly enough, there are two different rose comb alleles, R1 and R2. Only R1 is associated with lowered fertility. Homozygotic R2 roosters do not show the reduced fertility seen in homozygotic R1 roosters.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3386170/

 

[The Yakima Kid]

The fertility issue is ONLY with the roosters "pure"(homozygous) for rose comb. Roosters with only one rose comb gene do not have fertility problems. Hens with rose combs have zero problems with fertility, even if they are pure for it.

As Krys mentioned, it has to do with sperm from roosters pure for rose comb having problems with shorter lives, and IIRC, higher % of deformed sperm too, not sure if that's right..

A rose combed roo with just one copy of the rose comb will have perfectly normal fertility and will be able to breed 22 girls with normal fertility. Likewise, a single combed roo will produce normal fertility with a flock of hens pure for rose comb.

Pure rose combed roos do better either single mated or trio mated(common practice with show stock/show breeders).. especially if he is one of those roos that highly favor only a few hens out of a flock- otherwise the fertility problem will become very apparent.

There are two rose comb alleles - R1 and R2. Only R1 is associated with reduced fertility.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3386170/