| Normal Splits and Pearl Males Copyright © 2004 & 2006 by LINDA S. RUBIN CF Genetics Consultant/Panel Judge www.CockatielsPlusParrots.com Adapted from "My Mailbox" Q. I am trying to understand what colors my Normal Grey male may carry as a split. What visual clues should I look for? He has a tiny white spot on the back of his head and his wings have a tiny bit of yellow splotching on them, with an occasional feather that is mostly grey with a hint of yellowing. What is this yellow color on the wings? Could it be an indication of liver disease? He just turned three years old, so I am beginning to think of breeding him. A. A small white or yellow spot on the back of the head, nape, or on the chest, signifies a cockatiel that is split to Pied. To date, Pied is the only mutation that demonstrates a phenotypic mark in other varieties to signify this heterozygous state. Or, more simply, the Pied variety is the only mutation in cockatiels that can be visually identified as a split in other color mutations. A state of being “split” means that a bird can carry the trait and pass it on to its offspring without showing it outwardly. The yellow on the wings (and back) could indicate one of two occurrences. First, it is not uncommon for some Normal Greys to show yellow or white “marbling” if the grey melanin pigment does not provide full coverage. This is regarded as a show fault - although it is minor because color depth and uniformity is only 10% of Show Standards. You did not mention how long you have owned this particular bird or whether you have owned him since his baby/juvenile or adult molt. However, another possibility is that your male is a Pearl mutation that has been losing its pearl markings once it reaches full maturity. However, from the photos you have sent it does not appear to be true pearl lacings, but rather, a reduction of grey melanin pigment revealing yellow carotenoid pigment beneath. Yet, this is only a minor fault; select a well-colored hen to correct this if you should decide to breed this male. Technically, the yellow (carotenoid) pigment appearing on the white wing bar is a show fault although frankly, few judges seem to notice. Often times, such birds are selectively bred for more yellow pigment and it is therefore not unknown that birds from these lines - even Normal Greys - may show that influence with yellow extending into the white wing bar area. You may want to refer to the article, "Tick Markings and Split Pieds," in this section of the Color Mutation Archives. I would not worry about your bird having liver disease as it appears this is more a matter of color genetics and normal pigmentation. However, if you have any doubts, it is always best to rule out any medical condition by bringing your cockatiel in for a veterinary exam with an avian specialist. Many times, cockatiels with liver disease may show subtle signs such as a thinning and elongation of the tip of the beak, overgrown or thin, brittle nails, fatigue, depression and/or an “unwell” look in the eye. Experience with normal behavior in our birds allows us to become familiar with any abnormal signs of illness. Liver disease among cockatiels is fairly common, so if your bird demonstrates any of these signs or other symptoms, it should be seen by an experienced avian veterinarian as soon as possible. Never breed a cockatiel that has liver disease. The stress of breeding would cause further damage to the liver and further hasten its demise. Additionally, there is the possibility of passing on the trait for developing liver disease to future offspring and perpetuating the malady in the line. We must always breed responsibly and not pass on damaging traits to future generations. Learn more about genetics and mutations, view |
Copyright 2006 Linda S. Rubin
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| NORMAL SPLITS & PEARL MALES Copyright © 2004 & 2006 Linda S. Rubin ~ All Rights Reserved ~ |
| c.2006 Alyssandra Young (click on thumbnail to enlarge image) |