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The white Marans was very widespread in the sixties, during its "semi industrial" era. Then it was abandoned in 1966 in the favor of the commercial hybrids, and it progressively disappeared. Considering its quasi-extinction, we can speak of it as a resurrected variety in France …
It's resurrection dates back to about 1990, the White is nowthe most fashionable variety in France.
Description of the White Marans
The plumage must be white on the whole body without any red, black or fawn feathers. The shanks must also be white or pinkish as for most of the Marans varieties.
However, in the white-colored cocks, the hackle, the shoulders, and the lancets can be straw-colored, a characteristic that has been tolerated in the Marans breed.
White plumage genetics in the Marans
The genetic characteristics responsible for white feathers are not genes that produce a white color, but genes, which prevent the deposition of color into the feather. The white plumage is due to genetic characters, which mask the existing underling plumage colors.
White is not to be confused with albinism, which are clearly different at the genetic factor level and produce an absence of all pigmentation including the eyes, which are pink.
The two main genes, which are responsible for the white plumage in chickens, are:
- - the Dominant White which has the symbol (I)
- - the Recessive White which has the symbol (c)
Dominant white (I)
As this characteristic is dominant, crossing a pure white bird (I/I) with a colored bird gives birds with white plumage (I/i+). The initial color (black, fawn, wheaten, cuckoo) will be masked or veiled. This gene has most effect on black, however is not completely effective on red, which can result in the Pyle pattern. By selection we can obtain Dominant White in a homozygous state, the main breed based on this gene are the White Leghorn, it is also found in some White Marans stocks. Dominant White is known as a leaky gene as it doesn’t fully suppress black and the odd feather may appear.
Recessive white (c)
Recessive White when crossed with a colored bird produces C+/c chicks, which are colored. For example a Recessive White hen crossed with a Black cock produces black (colored) chicks in first generation. These colored birds, even if they have no visible white feathering, carry the Recessive White allele, c, that they are able to pass on to their descendants by what is called the atavistic return of the white genes (c).
So the mating between two normally colored birds that are carriers of the (c) allele in the impure state (heterozygote) will produce about 25% white birds. The genotype for these white colored birds is (c/c), as (c) is present in the homozygous state. Breeds with recessive white are numerous: they include White Marans", Dorkings, and Wyandottes… Recessive White is also a leaky gene not fully suppressing the gold/red spectrum, so a yellowish sheen on the hackles, the back, the shoulders and the lancets of the cocks, may appear after the adult moult.
Note: the chick down may be either light yellow-colored or grayish-white (or smoky white)
The Selection Os White Marans
An examination of the good qualities and the faults of the best current white stock allows us to define three main lines of action for the improvement of the White Marans:
- - to improve the egg color by an out of variety mating, preferably by the use of Wheaten birds,
- - to sort out the serious and too much frequent anatomic flaw, such as the problem of split wings. This can only be achieved by test mating.
- - to select, first and foremost, the white shanked birds in order to get to obtain 100% of birds with pinkish white shanks.
- but not neglecting the selection for pure White birds
In respect to this, we must stress the fact that a White Marans pen, were all the breeding stock have blue or lead-gray feet, can’t produce white shanked birds.
Indeed, the Dermal Inhibitor (ID) characteristic which assists in producing white shanks, and is dominant, and can't miraculously be revived from breeding stock with gray feet, because they have the id+ gene, a recessive). So as far as possible use a white-shanked cock.
The effects of crossings with White Marans
To the Brown-Red, this will have no improvement on the color of the White plumage. Indeed it may cause gold tints in the hackle & lancets of the male. Whilst this cross may improve egg color, shank color will certainly not be improved.
The Wheaten and Black-tailed Buff varieties, due to their red and buff pigmentation, may also harm the plumage purity of the White Marans by introducing unwanted gold hackle & lancets tints. The egg color and shank color may be improved.
The introduction of a Silver Cuckoo bird will improve the White plumage, but not shank color. If lines of good dark egg color birds are available it will also improve egg color.
Today, it appears that there are a good number of birds with white shanks in the present White Marans lines.
As for the method of the crossings to another breed (for example with the White lancets can be straw-colored, a characteristic that has been tolerated in the Marans breed.
The outcross to another breed rapidly damages the genetic characteristic of the extra reddish-brown egg color, leading to an egg color recovery selection, which is long, fastidious and even insurmountable in the White Marans variety. Only inbreed crossings are required for the improvement that can only be obtained by the indispensable supply of the genes, which are contained in the genotype of other Marans varieties.
As the improvement of the White Marans egg shade is at the current time the top priority, it is especially advisable to carry out useful cross breeding to Marans varieties whose eggs are the darkest possible color.
It is advisable to remind you in this respect that the color which is the most suitable to cross for the best white plumage qualities of all our varieties is paradoxically the pure black colored birds (Black & Silver Cuckoo), especially if Dominant White is present in the White parent. Black is unfortunately a very rare color in the Marans and Silver Cuckoo can have problems with egg color quality and shank color.
Anyway, such "in-variety” crossings, if they proved to be essential, must be followed up with a selection plan for a minimum of several years.
Genome of the White
The best White would be produce by the following, for the cock E/E I/I c/c S/S B/B W/W Id/Id Pti-1/Pti1 and the hen E/E I/I c/c S/- B/- W/W Id/- Pti-1/Pti-1
but White may be based on any ‘e’ allele, only Dominant or Recessive White may be present, cuckoo/barring may also not be present. The Dermal Inhibitor must be present in order to get white shanks in the cock, but even this will not give a white shank in the hen. |