Добавлено: 15 фев 2010, 18:41
Не знаю - что такое аллели и локус , но осмелюсь вставить слово своё неуклюжее в разговор просвещенныХ дам. В паутине достаточно много рассуждений от японцев и не японцев о перспективах скрещивания разноцветных акит... Аргументированных и не очень... Они обходятся без упомянутых выше аллелей и локусов. Возможно они примитивны. От того - мне близки. Йаху лехко их обнаружит... К примеру: "The Akita colour geneticsBruna (olovo jr.) писал(а):спасибо:) Буду думать.
Честно говоря, я как ни напишу аллели, у меня то тигры не могут дать рыжих, то рыжие не могут дать тигра...:( Ерунда какая-то....
А насчёт белых акит - почему вы решили, что это пятнистость?... я вот склоняюсь к тому, что к пятнистости это как раз не имеет отношения, и это типа как самоеды - в другом локусе вообще... Не? Или есть всё исследования именно белых акит по этому признаку?...
(полный бардак и каша в голове, блин)
The basic colours of Akita dogs are red, which also includes sesame colour which consists of red hair with black tips, white and brindle. The desired red colour resembles that of ”red dust” or “red sand”.
Brindle are here called “Br” > White “Wh” > Red “Re”, which means that:
Brindle dominates over red, which in turn dominates over white.
A mating between a BrBr and a ReRe dog = F1 generation: BrRe
F2 generation: BrBr BrRe BrRe ReRe = 3 Brindle, 1 Red
A similar situation exists between brindle Br and white Wh = 3 Brindle, 1 White.
However, in the case of brindle BrRe x brindle BrWh, the outcome is = BrBr BrRe BrWh brindle and ReWh red or white (according to the foregoing factor, ReWh would be red).
Re x Wh should theoretically produce no brindles, but brindles do appear, depending on the parent’s colours. This is not easily explainable, but a brief explanation is in order.
Brindle. Should a red appear from Br x Br (BrBr or BrRe or BrWh), one may assume that ReRe or ReWh were involved. Reds from brindle parents (in this case, both parents may be from the same litter) have never produce brindles, only reds or whites.
However, if both parents are brindles or if one parent is a brindle, red x white will produce brindle(s). Their offspring will probably be brindle, red and white. It has been reported also that a brindle stud dog of over one thousand offspring has never produced a red offspring. This may be due to BrBr which seems to be very dominant. One theory says that the brindle colour amongst the Asian dogs is caused by the same gene that produces “tabby” (turtle colour) amongst e.g. cats and this theory is strengthened by the fact that the stripes are unevenly dispersed which gives them an impression of being somewhat “untidy”.The brindle colour come as red-brindles, silver-brindles (snow brindle) or black-brindles.
White. The white Akita is a “bleached” red or brindle colour, caused by the chinchilla-genes influence on the colour genes (does not influence the black colour). The difference can be seen on the purity and intesinty of the colour and with knowledge of the parent’s colours. A red x white will often produce a somewhat cream-coloured shade of white, while a brindle x white will produce a “blue-tinge” to the white colour. The latter is the most desired.
Akitaens
fargekoder
ay
B
C
cch
D
E
em
ebr
e
G
m
S
si
sp
sw (?)
T
t
ay
Limits dark pigmentation and produces red coloured dogs
B
The Akita is, genetically speaking, a black dog (black nose, eyelids, etc.)
C
He may have full colour pigmentation
cch
Chinchilla-gene which bleaches all colours except black
E
Allows dark pigmentation all over the body
Ebr
The brindle colour is dominant
e
He may lack black pigmentation in the coat colour e.g. red.
si
”Irish spotting” or the white pattern on an Urajiro dog.
T
”Ticking” or spots in the white regions (eg. nose, legs)
t
Clear white areas without the ”ticking”
Urajiro (si = ”Irish spotting”). Selective breeding/inbreeding in Japan on this particular colour pattern has entrenched it. There isn’t any variety of the Urajiro on the red colours today, with exception of a white bliss, spot on the neck, half/full collar. This is accepted if it isn’t excessive. The brindles do not necessarily need to have a complete Urajiro but it has to “suit” the dog, as the Japanese express it. However, the more Urajiro the better.
Modifying polygenes produces the soft transition of the Urajiro and also increases/decreases the spreading of the white markings in si.
Rufusgenenes enhances the colour intensity.
Umbrosgenenes manages the ”shades” in the coat colour.
For those interested in learning more I recommend the following litterature:
"The Inheritance of Coat Colour in Dogs" by Clarence Little
"Genetics of the Dog" by Malcolm Willis"
http://home.online.no/~kintos/britt/eng_tre.htm
или
http://www.shohagoken.com/shohagoken/in ... offset=-1n
и так далее...
