Dwarf Cornish Cross, Breeding experiment

[Ridgerunner]

I can't help with the dwarf gene. I've tried but can't get my head around the different genes and what the outcomes will be.

The dwarf gene is a recessive sex-liked gene. I have to think about it but I can eventually figure out who will give it to whom. But what are the practical outcomes of that? That can get confusing really fast.

I don't know if them being dwarf helps keep them alive so they can breed or if the benefit is that they eat less so they are cheaper to keep as breeding birds. If they are miniature Cornish X and grow as fast aren't they going to have the same health problems? To me, costing less to feed isn't a big deal at our scale, we don't keep that many. But if it makes it easier to keep then alive so they can breed, that would be huge.

You'd have to figure out how to keep it in the right birds in your breeding flock. Do you want it in your boys only? Your girls only? Would you need to keep a separate flock to manage that?

Would you be happy with a miniature CX. They would put on meat really fast but the final product would still be miniature. There are only two of us, I'd be OK with that but if you are feeding a family of seven, maybe not.

Are you crossing them with dual purpose chickens or trying to breed them to themselves? I could see breeding a dwarf CX hen to a dual purpose rooster. Since it is a recessive gene all the offspring will be "big". But how do you maintain that through the generations? Is that what you really want?

I'm sure I'm missing many implications of this. I always do. But it is a fascinating problem. Good luck.

 

[CSKA]

The dwarfing gene is not only recessive but it is sex linked. That means a hen will give it to her sons but not her daughters. If you breed a dwarf CX hen to a DP rooster the offspring will all be regular size. The pullets will not have the dwarfing gene at all, the cockerels will be split with the recessive dwarfing and dominant not-dwarf.

For a CX cockerel to be a dwarf he has to be pure for that dwarfing gene. If you cross him with a DP hen all the pullets will be dwarf. The cockerels will all be split dwarf-not dwarf and regular sized.

Hopefully that will help with your breeding. The gene being sex linked should help. Where I cannot help you is in how to keep them alive long enough to breed. With them being smaller feed costs will go down, but I'd think you could still have issues of them getting too big too fast. I just don't know.

So this means that if I manage to get a male CX to live enough to breed with a heritage normal female, and no dwarfs appear, it means I got 50% lucky and manage to weed out the dwarf gene from this cross?

 

[Ridgerunner]

So this means that if I manage to get a male CX to live enough to breed with a heritage normal female, and no dwarfs appear, it means I got 50% lucky and manage to weed out the dwarf gene from this cross?

It kinda depends on how many pullets you hatch out and how lucky you are. With your cross to a "normal" dual purpose hen all male offspring will be "normal" sized because the dwarfing gene is recessive and the mother doesn't have any to give. So the male offspring don't tell you anything.

If the Male CX has one recessive gene then there is a 50% chance one of his daughters will inherit that gene and be dwarf. That's a 50% chance for each of his daughters. If you hatch:

2 pullets there is a 1 out of 4 chance both will be full-sized
3 pullets there is a 1 out of 8 chance all 3 will be full-sized
4 pullets there is a 1 out of 16 chance all 4 will be full-sized
and so on.

It is hard to be sure you actually eliminated a recessive gene. That's why some can show up several generations later if you inbreed. But the more pullets you hatch the more sure you can be.

 

[CSKA]

It kinda depends on how many pullets you hatch out and how lucky you are. With your cross to a "normal" dual purpose hen all male offspring will be "normal" sized because the dwarfing gene is recessive and the mother doesn't have any to give. So the male offspring don't tell you anything.

If the Male CX has one recessive gene then there is a 50% chance one of his daughters will inherit that gene and be dwarf. That's a 50% chance for each of his daughters. If you hatch:

2 pullets there is a 1 out of 4 chance both will be full-sized
3 pullets there is a 1 out of 8 chance all 3 will be full-sized
4 pullets there is a 1 out of 16 chance all 4 will be full-sized
and so on.

It is hard to be sure you actually eliminated a recessive gene. That's why some can show up several generations later if you inbreed. But the more pullets you hatch the more sure you can be.

Thank you so much, so if I understood correctly:


1 CX female X 1 Heritage male (I should keep resulting females for reproducing - no dwarf gene guaranteed).

1 Heritage female X 1 Freedom Ranger male (I should keep the resulting males for reproducing - no dwarf gene guaranteed).


So now by crossing this 3rd generation, I have eliminated the dwarf genes, and I should have a bird that is balanced between the fast growing genetics of "industrial" birds and heritage and which can be reproduced at home. Am I correct?

 

[Ridgerunner]

I don't know if the Freedom Rangers have the dwarf gene or not. I've read both ways. If I were doing this I'd get a few CX females and a heritage male and keep both male and female offspring for breeding. Or keep a heritage male and a female Freedom ranger. As long as you only keep female CX or Rangers for breeding you should have a no-dwarf gene guarantee. If you use a male of either you have the risk. I don't know how high that risk is but it is not zero.

 

[Klutch]

How would it be, if you breed that CX roo with a Bantam Cornish?

 

[Ridgerunner]

Artificial insemination isn't that hard once you learn how to do it.

 

[Klutch]

How would it be, if you breed that CX roo with a Bantam Cornish?

I hope those eggs wouldn't be to big for the hen, since their 50/50.