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Breeding Questions
Question: I have a Normal cock who's
mother was a Lutino and the father was a Pearl. I was told these are sex linked
color genes and since a cock has two chromosomes where a hen has only one, the
Lutino color occupies one chromosome and the Pearl occupies the other. If so,
why am I getting Normal females? If this is information is correct I should only
get Lutino or Pearl hens, as it takes only one sex linked gene to produce a hen
but two to produce a cock? D.F. KS
Answer: What you have been told is
correct. The information you were given doesn't take into consideration
crossover and reverse crossover. When you have a normal cock split Lutino(XL)
and Pearl(XP) it would be diagrammed as XL x XP. When crossover occurs, one of
the sex linked genes relocates to the other chromosome, making your chromosomes
Xn x XLP. It is when the XLP chromosome bonds with the females chromosomes that
a Lutino-Pearl chick is produced, just as when the Xn chromosome, above, bonds
with the females chromosome a Normal is produced. In the March/April issue a
similar question was asked dealing with a Normal/Cn/L. The percentages given
were as follows:
25% Normal hens 20% Normal cocks
25% Lutino hens 20% Normal split Lutino cocks
25% Pearl hens 20 % Normal split Pearl cocks
25% Lutino-Pearl hens 20% Normal split Lutino and Pearl
(crossover) 20% Normal split Lutino-Pearl
(crossover) cocks
Also, as previously stated these percentages are based on the pair producing
100 chicks. The above crossover percentages are approximated. As crossovers
occur at random, crossover percentages always vary from pair to pair, I believe
the actual percentages of Normal and Lutino-Pearl hens produced should fall in
the range of 12.5% to 25% with a higher percentage of Pearl hens and
Lutino hens being produced.
CLARIFICATION: Reference the article on Cockatiel
Genetics in the January/February 1996 Magazine. The article was interesting and
fairly easy to follow(genetics being as they are), there was one significant
error. It was stated that it was impossible to tell clear Pieds from Lutinos. I
have been raising clear Pieds for several years and there is an obvious
difference-clear Pieds have black eyes not red like a Lutino. In addition, if
clear Pieds have been selectively produced, they will not have the bald spot on
the head, which is unfortunately still common in the Lutino. C.C.TX
REPLY: Thank you for your concern for the accuracy of
the information in these articles. All Lutinos and Albinos do have red eyes of
some shade or depth of color. But, not all red eyes are readily identifiable
without the aid of a flashlight or other bright light being shone directly into
the birds eye at extremely close range. I believe a previous article describes
the traits that some lines of Lutinos and Albinos exhibit in having bright red
eyes, dark ruby red eyes at birth and others where the bright eye darkens to the
ruby red color as the bird ages. It also describes a cross breeding that ensures
a bird will retain the bright red eyes its entire life, this being a cross
between the Lutino and the Pied, the Lutino-Pied. The bald spot on Lutinos and
Albinos is not as common as you might think, since their appearance, breeders
and exhibitors have selectively worked to eliminate the bald spot and increase
their size. As long as ten years ago A.C.S. had breeders producing Champion
quality Lutinos with no bald spots. It does take longer for the pet trade to
eliminate flaws that appear in any mutation, but the Lutinos faults are becoming
less and less common with each breeding season, with most getting larger and
having no bald spot at all. You also mention the bald spots on the Pied, it is
my understanding that when the Pied first appeared it did have a bald spot, but
the bald spot has disappeared in the same manner as any flaw in a new mutation,
through selective breeding. If the Lutinos in your area are small or have bald
spots and you are currently having to selectively breed your Pieds to eliminate
baldness, I would recommend purchasing some unrelated stock from a reputable
breeder outside your area. The reason I recommend this is, when cockatiels are
continuously line bred, the flaws that have previously disappeared or
suppressed, can reappear and crossing out to new stock is used to revitalize and
stabilize a blood line.
I continue to receive letters where individuals have purchased clear Pieds,
thinking they were Lutinos, then bred them with a Lutino hen and produced only
Normals. This happens all over the country and is not limited to just one area,
indicating there are many dark eyed Lutinos and many clear Pieds being mistaken
for them.
Keep in mind when breeding Pieds, the ACS Standard of Perfection states the
ideal Pied is 75% clear and 25% dark, recognizing a Pied for its markings
not its lack of markings. For this reason the clear Pied is at a disadvantage on
a show bench and in less demand than a well marked (symmetrical patterned) Pied
of equal size.
Totally clear Pieds are impossible to tell from a Lutino with dark red eyes,
as are the totally clear Whiteface-Pieds impossible to tell from the
Lutino-Whiteface(Albino) when it has dark eyes.
Thank you for bringing this to my attention so I could clarify that the
Lutinos needed to be of the dark eyed variety.
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