Breeding for meat qualities in a sustainable dual purpose breed

[seriousbill]

Quote:
I've read the articles you are referring to. From Chapter 1 (Meat Qualities):

A producer needs far fewer males than females to be
retained for breeding stock. With this in mind, rigorous
selection of the males is an important component to a
sound, breeding program. It should also be remembered
that adult size is controlled by the size of the female
stock – under-sized or otherwise poor quality females
should not be retained. Better to hatch more chicks
from fewer hens, than to retain under-sized or poor
quality hens to increase flock size.

It is unclear to me whether the author is saying that hens have genetic control of size (something that I haven't found in any serious breeding documents) or whether he is just making an observation that hen size is just as important as rooster size and should not be overlooked. If anyone has a pointer to a study addressing this issue, I would appreciate it if you'd mention it in this thread.​

Hi Tim, my understanding is that size is a polygenic trait, controlled my multiple genes, and is not a simple sex-linked one, so the hen doesn't control size exclusively. This is pretty straightforward when you think about breeding a bantam and a standard together. You tend to get an intermediate bird, no matter which parent was the bantam. This is more or less common knowledge in genetics, so I doubt there would be a study dedicated to that question alone. I took the above quote to mean that it's unwise to expect a large roo to carry the size of the flock. People do tend to overlook the size of their females, so that is good advice. Hope this helps.

 

[TimG]

Quote:
Yes, that is what I think the author meant. But, I can easily see how someone might think otherwise.

You would think that if one sex had more control over the size of offspring there would have been a study with published results. Since there doesn't appear to be any such study and results*, that is a strong indication that size of offspring is not controlled more by one parent than the other.

* That I have found in my searching.

 

[TimG]

Quote:
I gave these colored rangers some thought and was turned off for two reasons:

1) The colored rangers journal reported an average dressed weight of 3 1/2 pounds after 12 weeks. I'm hoping for a bigger bird, though maybe these guys would satisfy that requirement if grown to 16 weeks. 16-18 weeks is not a problem for me, but when combined with #2...

2) Being a cross, I did not think they would breed true. Your report that the offspring follow their parent's coloring, growth, weight and temperament has me reconsidering.

3) There is a fellow named Tim Shell from VA who had a sustainable line of meat chickens going from an original cross of Delawares and Cornish X.

I've read his winter 2003 article that discusses the program. It was my impression that he created the Corndell by "improving" a commercial Cornish Cross by breeding in 25% Delaware and maintained the new line with a carefully restricted diet. The Improved Pasture Peeeper is nothign more than a "standardized, commercial, Cornish Rock cross". It really sounded to me like he was primarily being very careful in his maintenance of a line of commercial Cornish crosses.

Thanks for the shared ideas from everyone.

Yes, please keep them coming.​

 

[Krys109uk]

While it isn't really relevant to your project &, as you say, quite a lot genes related to size have been found.
Considerable research was done into incompletely recessive gene sex linked dwarfism dw. I don't know whether this is still used by the meat industry but females with the dw/- gene were used as they were smaller, took up less space & consumed less feed. These dwarf females being mated to non dwarf males all non dwarf female offspring & heterozygous males in which the effect of the one dwarf gene has only a small effect during the few weeks to slaughter.

 

[Ryu]

Quote:
It is unclear to me whether the author is saying that hens have genetic control of size (something that I haven't found in any serious breeding documents) or whether he is just making an observation that hen size is just as important as rooster size and should not be overlooked. If anyone has a pointer to a study addressing this issue, I would appreciate it if you'd mention it in this thread.

The breed comparison chart is a bit odd. It seems that in every other source the Buckeye is considered slower maturing, but in this chart is says medium (16-20 weeks). It also lists the Jersey Giant as medium (16-20 weeks). In other reading it has been said that Jersey Giants are amongst the slowest to pack on the meat. Two people in this thread have suggested that Marans are the fastest growing breed they know, but those are also listed as medium (16-20 weeks).

The chart includes an note that "Much of this information was gleaned from the catalog published by the Sand Hill Preservation Center, Calamus, Iowa" so the notes on this chart might be connected to where Sand Hill is in their progress towards attaining their goals?

For all that, there are three breeds on the chart that are listed as fast growing: New Hampshire Red, Delaware and Plymouth Rock. Of those, only Delawares have a note for "rate of lay" (that note is "very good").

I think the last setence on the paragraph is what the author truly ment. I am a Geneticist by trade, and reading these articles can be frustrating. The 'old timers' are certainly not technically correct when they talk about inheritiance and heritability of traits. If you sift through their advice, they'll be wrong about why it works, but most of it holds up in practice.

As forthe chart, it depends on who you get your stock from. Questioning the breeder usually reveals, "Well I did use a Rock roo two years ago. or I put that Cornish hen in last year..." Getting your hands on the real deal can be a challenge.

 

[walkswithdog]

And in regards to dual purpose birds there really are a huge bunch of useful discussions ON the Meat Bird Thread. It's where we usually discuss meat birds because a lot of folks here would rather not discuss their pets or show animals as something butchered.

I started with Partridge Rocks and especially as hatchery stock, they're not suitable. Rate of lay is great, size and fullness of breast - not good.

This year I brought in Delawares from three sources. They show a LOT more promise in growth rate. Heritage dels grow wicked fast, good breeder Dels grow a tad slower but well and hatchery dels slower yet, so consider your sources.

I'm going to see how the Dels, grow/lay/produce and butcher out.

I may do a run of colored broilers in fall to check them out when I have my keepers sorted out. Many folks having success with them as they are or mixed in with breeds like Dels/Marans.

I've brought in some larger rocks so I'll probably keep Rocks in my meat pen mix over the long haul.

12 to about 16 weeks works here since most of the year mine free range during daylight.

Just a side note, hybrid vigor of captive domestic-bred species is a social myth. Hybrid vigor applies to non-captive, unselected species/matings where natural selection and free mating occur. Whenever man influences the environment, feeds an animal, contains it or has a hand in matings - matings are not truly random, are not from naturally selected groups and therefore suffer the same fates/problems as all domestic bred species.

 

[TimG]

Quote:
I considered posting to the Meat Bird forum, but decided that this was more about genetics and that those experienced in breeding would have more valuable input. I continue to read the Meat Bird forum for any information that might be useful.

This year I brought in Delawares from three sources. They show a LOT more promise in growth rate. Heritage dels grow wicked fast, good breeder Dels grow a tad slower but well and hatchery dels slower yet, so consider your sources.

I'm going to see how the Dels, grow/lay/produce and butcher out.

I hatched some Delawares last spring and butchered them last fall. I bought the eggs from a somewhat random online source before I had done much research. I was disappointed by their size (and just as disappointed that I did not weigh them before and after processing). I'd be very interested in reading about your results and sources.

Just a side note, hybrid vigor of captive domestic-bred species is a social myth. Hybrid vigor applies to non-captive, unselected species/matings where natural selection and free mating occur.

I have been reading Poultry Breeding Applied by F.A. Hays which was published in the 1940s. There is a chapter on crossbreeding which says "This type of breeding has rather wide application in the broiler industry because the usual stimulating effect of hybrid vigor is shown by the early growth rate of hybrid chicks." The author goes on to cite some studies which seem to generally indicate that hybrid chicks experience more rapid growth up to about 12 weeks, but often slow after that so that mature weight in hybrids is in line with that of the corresponding purebreds. These studies were done with captive birds.​

 

[Kev]

Quote:
A caveat- pea comb also reduces the overall number of feathering on a bird. Naked & less feathers doesn't seem to bode well for a bird in a cold winter area.

Also, I got Madagascars from a hatchery 2 years ago, they proved to be highly variable growers.. some real slow, others medium. As adults they were very heavy for their size though.

 

[walkswithdog]

Quote:
I considered posting to the Meat Bird forum, but decided that this was more about genetics and that those experienced in breeding would have more valuable input. I continue to read the Meat Bird forum for any information that might be useful.

This year I brought in Delawares from three sources. They show a LOT more promise in growth rate. Heritage dels grow wicked fast, good breeder Dels grow a tad slower but well and hatchery dels slower yet, so consider your sources.

I'm going to see how the Dels, grow/lay/produce and butcher out.

I hatched some Delawares last spring and butchered them last fall. I bought the eggs from a somewhat random online source before I had done much research. I was disappointed by their size (and just as disappointed that I did not weigh them before and after processing). I'd be very interested in reading about your results and sources.

Just a side note, hybrid vigor of captive domestic-bred species is a social myth. Hybrid vigor applies to non-captive, unselected species/matings where natural selection and free mating occur.

I have been reading Poultry Breeding Applied by F.A. Hays which was published in the 1940s. There is a chapter on crossbreeding which says "This type of breeding has rather wide application in the broiler industry because the usual stimulating effect of hybrid vigor is shown by the early growth rate of hybrid chicks." The author goes on to cite some studies which seem to generally indicate that hybrid chicks experience more rapid growth up to about 12 weeks, but often slow after that so that mature weight in hybrids is in line with that of the corresponding purebreds. These studies were done with captive birds.​

I'm going to be weighing the largest dels - live weight for records next week. I'll post results.

That it was a 1940's article on breeding siting hybrid vigor is common for the era. Any solid outcross to another line or other breed can produce the same benefit. It's outcrossing that is of benefit. If it is of benefit and not detriment.

They were taking significantly inbred lines and outcrossing - tada better results.

They probably got better fertility too.​

 

[Happy Chicken Mama]

This is g.r.e.a.t.