It’s hardly stopped raining since early summer and at the time of writing this the whole farm is waterlogged and mud everywhere. The fixed outside runs have been strawed down each week with a bale of wheat straw and now I’m having to buy it in very large bales that are 8ft x 4ft and hold around 15 normal bales. I can just litter down all the runs with a very large bale, but it’s expensive this time of year after the farmers have handled it into the sheds. Off field at harvest time a big bale was £10, now they are £20, both collected.
The birds are looking OK and a number of this years pullets are in lay. The cockerels have been selected for next season and most of the others are now in the freezer. Of this years pens the best came from a group headed by an Australorp Cock running with 4, 2cnd generation Welsh Black hens. The resulting pullets are lovely birds. Tight feathered and full bodied. Single comb, black legs and eyes and white soles and claws to the feet. This is where I wanted to be with this line. As near to my ideal of a perfect Australorp without all the fluff bred in by exhibition breeders. The weight and size is there and everything about the 2 I have selected says vitality.All I need to do now is see what numbers of eggs they lay. Besides these two I have a number of growers from the same pen coming along well, but being hatched later the amount of daylight feeding time they have had is a lot less than earlier hatched birds,so they will mature in the spring and I’m expecting slightly smaller birds.
Creating a Utility Strain.
The genetics of poultry is a complicated theory and will take a lot of understanding unless you clear your mind and focus.
Chickens have about twice the genetic load as other animals such as humans. The genetic load is just a measure of the lethal equivalents in a genome. Humans have one of about 2.5.
This means you have the equivalent of about 5 recessive lethal genes in your genome.( 2.5 from your father and 2.5 from your mother) This is why brothers and sisters should not have children because they share half their genetic make-up and recessive lethals or detrimental genes can be expressed in the progeny of inbred matings.
Chickens have a genetic load of around 6. Nearly all inbred lines generated by full sib (Brother/Sister) matings fail after just three full sib matings. Once the inbreeding coefficient goes over 0.375 the lines tend to fail and fresh genes need to be added,but unless your in full knowlage of the genetic make-up of the blood your introducing in the line you will undo all the work put into your strain. You can add genes from the male or female line you started with or a strain run alongside the main strain, such as an uncle/brother of the original male (who was the best bird you founded the strain on).
So inbreeding (sibling mating) in chickens is not a very good thing to do a lot of if you are un-aware of the downside.
The reason people like to line breed is that it is the fastest way to select for type that is caused by a complex interaction of genes. If you have a superior animal the fastest way to increase the frequency of the superior genes in your line is to line breed.
Line breeding is just when you take the superior parent (Cock or Hen) and cross the progeny back to the parent (father to daughter or mother to son). You then take the superior parent and again cross it to its new offspring from the inbred mating. You repeat this until infertility becomes a problem or the parent dies, but only worth doing if you are breeding better or as good as the original bird/birds. If your not start again.
You can select other progeny that presumably will be better than average for your flock to breed in non inbred matings or to other close relatives to try and set the good traits in your line.
The reason that this works is that in the first mating the progeny have only half the sires genes. It stands that the inbreeding coefficient (F) is zero because none of the non inbred progeny can have both the alleles from the sire. When the sire is crossed to his daughter F = 0.25 this means that 25% of the genes of the progeny are identical by descent (both alleles of a gene come from the sire) and 75% of the total genome comes from the superior parent.
These first generation inbred progeny have been fixed for 25% of the sires genes. With the next inbred mating of sire to grand daughter F = 0.375 and 87.5% of the total genome. Mating to his great grand daughter F = 0.438 and 93.8% of the total genome comes from the superior sire. After this inbred mating the gain is much less (the next inbred mating results in F = 4.69 and 96.9% of the total genome) and the birds are getting pretty old, so you can pick the best son and start it over again.
Line breeding can produce very rapid gains in the quality of your line for certain traits, but nearly always results in a degeneration of the reproductive capacity of your line and you end up outcrossing and starting over.Eggs may become smaller or birds start losing vitality.
For a few generations it can give you some outstanding birds at a higher frequency than you would get by not inbreeding, but there is a downside. This is why commercial breeding companies try to avoid inbreeding and concentrate on improving the whole population. The gains are not as dramatic, but they don’t fall on their faces as often.
I use a line bred from a top quality male mated to an equal quality female. You should do a little inbreeding, but not a whole lot and if you inbreed I’d recommend parent to offspring inbreeding because all the genes that become homozygous by descent come from the superior parent. If you brother /sister inbreed you get about the same amount of inbreeding (0.25, 0.375, 0.5, 0.594, 0.672.) for the first few generations, but the genes that become homozygous by descent come from the superior parent and the inferior parent. So if you brother/sister mate you are not only fixing genes from the good parent, but from the not so good parent too.
Maybe the best advice is that if you inbreed always use a superior animal for the mating. If you do not you are just increasing the bad genes in your line.
Any mating between related individuals is inbreeding. Line breeding and full sib mating cause the same amount of inbreeding for the first two inbred generations. Theoretically line breeding and full sib matings should have the same detrimental results for the first two inbred generations. Full-sib mating would be more detrimental for the 3rd and subsequent inbred generations.
The difference is that all the inbreeding comes from the superior parent in line breeding, but half the inbreeding comes from the inferior parent in full-sib matings. This is why I’d recommend inbred matings involving only birds that you think are good enough to warrant it.
If you look closely at the above photo you can see the 3 cockerels have different coloured feathers and different coloured legs. All have the same comb shape and all carry the double muscle gene from Indian Cornish game. The bird with yellow legs was given that by his mother (Indian Game) and it will now carry the gene for yellow legs. The bird with pink legs got the colour from whatever genes came together at random from both male and female (Australorp cock X Indian Game Hen) that was surpressed in the genes of the birds involved, but came to the fore when either a dominant gene conected with a gene that allowed that colour in the leg to show up. The bird at the back with the black legs had that from his Australorp father, so will carry the gene as domminant for black legs IF another gene of the same type comes together in the offsprings.
In this picture the two males have the same comb type, the same leg colour and the same muscle mass on the breast (from IG). The French Copper Marans gave them the feathered legs and as I had used blue feather Marans some had the gene for blue feathers.
Why I used this mating was to get the gene for a darker brown eggs in the make-up and it worked The resulting pullets not only carry more breast meat, but lay a darker brown egg. Not as dark as the hens they were bred from, but a lot darker than the Welsh Black.
The amount of meat the cockerels carried wasn’t as much as the Welsh Black father had,but still as much as most half decent pure bred Light Sussex or Rhode Island Red have nowadays. The pullets laid well enough, but having to produce a darker egg resulting in the egg being held in the bird for longer to give it the shell colour than say a buff or white egg. The next generation would need either putting back to a pure Indian Game (grand parent line) or to a French Copper Marans to get a better egg colour (mother line, which would be the strongest, as it is nearer the genetic make-up of the pullets). If I followed this strain I’d start losing egg numbers, as both the Pure Indian Game and the French Copper Marans are less likely to produce lots of eggs. Mating the pullets back to an Australorp (grand parent line) would help or should help with egg numbers, but where do you stop?.
I’m happy with the Welsh Blacks. Lovely birds, calm and easy going. Good egg numbers and I’m eating plenty of chicken from the males. I can afford to be selective with the take outs from the selection process I use. I never take the females as table birds, but could if I was that pushed for meat.
There seems to be a growing interest in utility bred poultry and I’m glad this old tradition is returning. I have a book by Cook the guy who first developed the Orpington and he gives a number of breed he bred with a view to producing eggs and meat from the same lines. This publication preceded the development of Cornish Game and he used English Game cocks mated with a number of other breeds with varying degrees of success.
Back in those days (around 1890) Cochin and Brahma were very different to the birds we see now. The farmers of that period used Brahma X Cochin first crosses and they were a very popular cross. One wonders what that cross would produce today.
Without the input of Indian Cornish Game into a dual purpose breed I think your going to be disappointed by the resulting birds. No pure breed I have seen in the last 20 years gets close to what a first cross using an Indian Game male can produce.(if you can find some that are viable and most of the exhibition bulldog types are’nt)
The first cross is usually by far the best, but by careful selection and a well thought out breeding plan you can create a strain of birds worth spending valuable time working on.
I chose Australorps, as they were good layers and a large frame to put meat on. Dorking were my other choice, but alas they are shadows of their once top utility breed. Finding a good Dorking is like trying to spot a politician that’s doing it for the people and not themselves. Egg numbers are low. Vitality has being lost by stupid breeding practices and within the next 10-20 years they will (if not already) be lost forever.
Never be worried about the outcome of a X mating. If your birds are fit and healthy and you have an understanding that not all will be first class examples of what you expected to come from the pen.
Just remember if both male and female carry the gene for brooding you will double the chance of a heavy sitter. If you mated say Wyandotte to Cochin. If you mated a light breed like a Leghorn to a Wyandotte you may still get birds that sit but not as often, as Leghorns/Anconas hardly ever go broody. If you mate both birds from poor layers MOST of the off springs will lay poorly. Double the genetic possibilities for slow feathering and you will get the majority of the chicks feathering later than normal. If one bird in the mating carries a fault it will remain in the bloodline.
Go back and look at the picture at the start of this and look closely at the birds eye. It doesn’t quite fill the socket. That fault was put there by a gene in the female line that showed up 3 generation after the original mating. (I traced it back to a sister of the hen I had used. I scrapped that whole line and started again)
If it is your intention to breed a worthwhile bird with quality utility features please do your utmost to pursue your goal this coming season. I shall be downsizing my breeding plans over the next month or two as ill health and the amount of work keeping around 300 birds fit and well generates is a full days work 7 days a week.
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