Virgin Birth in Chickens

[centrarchid]

You would get a family of almost complete inbred clones! More like lab mice then a flock of chickens.

The main issue with extreme inbreeding like that is you can find all kinds of recessive mutations that can cause illness.

You can also use process to aid in identification of those parties (parthenogenic males) carrying recessive deleterious alleles and remove them from process used to found next generation. If a given male backcrossed to mother yeilds low survival in offspring, then he is probable carrier of bad allele(s).

 

[Poultry Friend]

If the son is showing bad alleles that is a sure sign the mother is carrying them and you need to cull her- never mind her son! LOL

 

[centrarchid]

If the son is showing bad alleles that is a sure sign the mother is carrying them and you need to cull her- never mind her son! LOL

Everyone carries bad alleles, no exceptions unless you are are homozygous for every locus and the bad alleles are all fatal. Such condition where bad alleles are not existent is not even realized in the purest, best bred inbred lines of games. The following I copied form same source you used.




DEFECTIVE CHARACTERISTICS: Now that we understand the important qualities of American Games, we must understand the defective characteristics these fowl are known to have, and to know what to watch out for. Here are the most common of these defects:



Crooked or duck toes
Knocked knees or bow leggedness
Squirrel tailed or wry tailed
Short wings or angel’s wings
Short neck
Sunken eye or irregular pupil
Sparrow’s beak or crooked beak
And the most misunderstood defect, beetle brow.


Many of those defects are genetically based. The rarer the alleles causing them, the harder they are to cull out. Inbreeding allows more rapid identification of carriers. Inbreeding, when done with an understanding of what inbreeding actually is and does can even be used not only identify carriers of a given allele but all purposely extract quality offspring from an individual that would otherwise be culled owing to a some combintation of undesirable alleles. Creation of parthenogenic male offspring from a hen would allow extremely rapid culling of undesirable alleles yet retaining the good one from the mothers of interest. Remember, females are the line and males are basically repressentatives of the lines capacity for performance and a mechanism for exchanging alleles between lines.

 

[Poultry Friend]

True, but by 'bad' I meant BAD. Like cancer or other serious health mutations. In that case culling that animals that carry it is best. And your point is the reason most good breeders keep the inbreeding coefficant at 12.5% or less. It allows for the good qualities to be passed on, but limits the homozygous genes to help keep bad ones from showing. In severe inbreeding like you are talking about, you will have no way to avoid them.

 

[centrarchid]

True, but by 'bad' I meant BAD. Like cancer or other serious health mutations. In that case culling that animals that carry it is best. And your point is the reason most good breeders keep the inbreeding coefficant at 12.5% or less. It allows for the good qualities to be passed on, but limits the homozygous genes to help keep bad ones from showing. In severe inbreeding like you are talking about, you will have no way to avoid them.

Under ideal conditions you do not employ inbreeding alone.

When culling out specific alleles, the 12.5% inbreeding coefficient does not always apply. The coefficient of 12.5% protects from loss of desirable alleles when considering breeding individuals within a population although occasional higher targeted inbreeding followed by oubreeding within a line or strain can be can be used to remove undesirable alleles yet salvage those that are desired. This involves a large number of inbreeding pairings where many resulting broods are removed in their entirety as individuals used to make crosses carrying undesirable alleles are identified. mating a given individual to more than one individual can speed process somewhat. The parthenogenic males would greatly speed up process because the males themselves and not their offspring could be used to identify the carriers of alleles in question.

You seem very knowledgeable for someone just getting into gamefowl.

 

[centrarchid]

I am usually assuming the really bad alleles are lethal. Alleles I deal with are usually not lethal in themselves but when in homozygous state and sometimes heterozygous state result in an individual being culled at one point or another. The parthenogenic male would really speed up that process. As bad alleles and allele complexes are are eliminated, the survival of parthenogenic males should shoot way up.

 

[Poultry Friend]

That is a bad assumption. Most of the icky ones will manifest as genetic illness and cancer past one year of age. That is all well and good if you plan to cull hens after one year and broilers at 15 weeks, but if you plan to have the birds around for a while and use them to breed, it is important to eliminate those alleles as well.

There are a lot of really nasty alleles that are not lethal but will cause all sorts of horrible things.

That is why it is important to keep some birds from each hatching around for a few years to see if their parents carry anything worth culling them for. It takes a long time breeding this way and you do end up culling some birds and their offspring when their grandkids show some bad mutations, but in the end you have some really healthy birds.

 

[Poultry Friend]

You seem very knowledgeable for someone just getting into gamefowl.

Thank you! I may just be getting into birds, but I have been in genetics and breeding for a long time.

 

[centrarchid]

That is a bad assumption. Most of the icky ones will manifest as genetic illness and cancer past one year of age. That is all well and good if you plan to cull hens after one year and broilers at 15 weeks, but if you plan to have the birds around for a while and use them to breed, it is important to eliminate those alleles as well.

There are a lot of really nasty alleles that are not lethal but will cause all sorts of horrible things.

That is why it is important to keep some birds from each hatching around for a few years to see if their parents carry anything worth culling them for. It takes a long time breeding this way and you do end up culling some birds and their offspring when their grandkids show some bad mutations, but in the end you have some really healthy birds.

I have three long-term chicken projects. First project involves American dominiques where must get beyond final round of culling at two years old before they can enter breeding population. Once they make it, producing more offspring over multiple breeding cycles / years will be a mechanism to promote longivity. Roosters will make final culling at about 1 year and will be taken preferentially from offspring of older hens. Second project similar except American game is being bred in to enhance free-range characteristics in a bird that otherwise conforms to SOP. Third is with American games where hens will not pass final culling until sons are pushing 2 years of age so hens will be 3 to four years old by then.

I also involve myself with genetics at work involving fish. At work family selection used with a lot more (in the 1000's) each year and all fish marked individually with PIT tags like used for dogs, cats and sometimes livestock. Their animals selected to meet target qualities by 18 months post-hatch. With the strictly food animals, long-term survival is not a quality concerned when animals tend to grow well beyond desired market size and fertility begins to decline or fish simply get to big to handle.