Page Title

ORIGINAL
BOOK REVIEW
by
Dr. Rainer R.
Erhardt
"Well, there is help on
the horizon and
anyone seriously
interested in color
genetics should take a
look at Linda Rubin's
book: COCKATIEL
G ENETICS MADE EASY!
Though this book is
primarily directed to
breeders of cockatiel
mutations, there is
enough information in
this little volume to
teach anyone the
secrets of dealing
with recessive,
sex-linked, and
dominant mutations..."
ACBM, Vol. 65, No.12
CLICK TO READ THE
REST OF THE REVIEW!
112 pages, 15 chapters,
glossary & more!

Multiple Bird
Households
by Linda S.
Rubin

Ultimate
Parrot Guide
by Linda S.
Rubin

click for descriptions, chapter excerpts, & reviews!

Series by
Linda S. Rubin

Tick Markings and Split Pieds
Copyright © 2003 LINDA S. RUBIN
CF Genetics Consultant/Panel Judge
www.CockatielsPlusParrots.com
All Rights Reserved
Selected Q&A's "From My Mailbox"

Q. I have two 6-week-old Normal Grey cockatiels that have several yellow
feathers on the back of their heads. Their mother is a Whiteface Pearl
and their father is a very light Lutino. What are they?

A. Yellow and/or white feathers appearing on the back of the head,
nape of the neck, or on other parts of the body are known as “tick
markings” and indicate a cockatiel that is heterozygous (split) to Pied.
Because Pied is a recessive mutation, the gene for Pied may be
inherited from either parent.

If your Whiteface Pearl hen is split to Pied, she has a 50/50 chance of
producing split Pied offspring of both genders. This simply means that
although the Pied mutation itself would not be visible, the affected chicks
would carry the Pied mutation in hidden form, which may – or may not –
be identified by tick markings.

Although many cockatiels that are split to Pied are ticked around the
head and neck, not all cockatiels that are split to Pied necessarily show
tick markings. Here is the catch; unmarked birds must be held until
breeding age when they can be testbred in order to discover whether
these birds carry the Pied gene when properly paired. Unmarked birds
that produce Pied offspring are still split to Pied; they just lack the
outward telltale tick markings; many split Pieds do lack ticking.

If your Lutino cock is split Pied, he also has a 50/50 chance of throwing
split Pieds of both genders. Furthermore, if both parents are split to
Pied, which you will find out over time, it is possible to produce a small
percentage of Lutino Pied cross mutation daughters.
However, the Lutino mutation can sometimes mask the Pied mutation so
that you won't necessarily realize that the chick is also Pied (i.e., Lutino
Pied). Most Lutino Pied cross mutations usually exhibit increased yellow
carotenoid pigment in their feathers and have obvious ruby-red eyes
compared to standard Lutino cockatiels. Standard Lutino cockatiels often
acquire additional melanin pigment in their eyes as they age.

If by chance your Lutino cock is a Lutino Pied (and if the Whiteface Pearl
hen does not carry the Pied gene), all of the chicks produced will be split
to Pied. These offspring, if correctly paired to other split Pieds, or visual
Pieds, will in turn pass the Pied gene onto the majority of their own
offspring in the next generation.

You can test-breed whether you have a Lutino Pied by mating it with
another Pied. In your case, a Lutino Pied cock mated to a Pied hen
would produce all Pieds however, the daughters would be Lutino Pieds
like their father, and the sons would all be Pied split to Lutino. (If the sire
were simply a Lutino cock paired with a Pied hen, the pair would only
produce Lutino/Pied daughters and Normal Grey/Lutino and Pied sons).

You stated that the father is a "very light Lutino." I am not certain what
this means. If your male is not a Lutino mutation, then other rules of
inheritance may apply. Some Lutinos carry a lot of yellow pigment, others
lack the yellow and are almost entirely white with the exception of some
yellow on the face and crest, and still others are an equal combination of
white and yellow pigment.

If your cockatiel does not conform to this description it is possible that
you have a very lightly colored Fallow mutation that is mostly whitish/light
tan feathering, with more yellow pigment on the breast (especially on
hens), and red eyes. Different strains of Fallows can show various
intensities of melanin (tan/brown) pigment and can range from extremely
light to a much darker pigment coloring feathers. Other color mutations
that could mimic Lutino are the red-eyed Recessive Silver mutation that
has very light melanin pigment, or the Double Factor Dominant Silver
mutation that has black eyes, rather than red eyes.

Whiteface is a recessive color that is inherited in the same manner as
Pied, so we know the two offspring you previously mentioned are also
split to Whiteface. Because the mother is also Pearl, any sons produced
would be split to Pearl (as well as split to Lutino from their sire).
Daughters produced would be visual Lutinos split to Whiteface.

The Pied gene will affect the outcome depending upon which of the
adults carry Pied, or whether both adults are split to Pied. If you are
fortunate to have both parents split to Pied, then expect future nests to
produce 25% visual Pieds (pp), 50% split Pieds (np), and 25% to LOSE
the Pied gene altogether (nn).

Because your first nest produced two ticked Normal Greys from a
Whiteface Pearl hen and Lutino cock, I would surmise that you have two
Normal Grey male offspring that are split to Whiteface, Lutino, Pearl, and
Pied. Again, this assumption is based on the argument that your adult
cock is a bona fide Lutino. Should your adult cock not be a Lutino, but
rather a different color mutation, it would then affect the color mutations
the resultant offspring carry in the recessive state.