| 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 GENETICS MADE EASY! Though this book is primarily directed to breeders of cockatiel mutations, there is enough information in this 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! |
Copyright 2006 Linda S. Rubin
| Multiple Bird Households by Linda S. Rubin |
| Series by Linda S. Rubin |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| Splits and Genetics Testing Copyright © 2004 LINDA S. RUBIN CF Genetics Consultant/Panel Judge www.CockatielsPlusParrots.com All Rights Reserved Selected Q&A's "From My Mailbox" Q. How do you know if a cockatiel is split to another color? Is there genetic testing you have to do? A. Some color mutations in cockatiels can be sexually dimorphic, which means you can identify genders and occasionally other hidden colors from certain pairings. This holds true with sex-linked color mutations (where the parentage is known) such as: Lutino, Cinnamon, Pearl, Sex- linked Yellowcheek, etc. For Example, if the sire is a Lutino, we know that any Lutino chicks in the nest are daughters and any grey chicks produced are Normal Grey sons split to Lutino. In the autosomal recessive color mutations, e.g., Pied, Recessive Silver, Fallow, Whiteface, Pastelface, etc., test breeding is the most non- invasive and direct method of finding out which mutations, if any, your birds could be carrying, depending upon parentage. For additional comments on cockatiels with tick markings, see "Tick Markings and Split Pieds" in the Color Mutations Articles. To the best of my knowledge, there is no “genetic testing” or gene mapping that has been done in cockatiels – they’ve only recently completed it in humans – that would allow a gene to be identified as a hidden trait carried on a particular chromosome identified by number. It is not impossible to accomplish this, it is just highly unlikely because scientists prefer to be paid for such difficult work and unless an individual or organization could offer that amount of money, there would doubtfully be any motivation to do so. Keep in mind too, that the appearance of mutational splits are found in accordance with percentages that are based on every 100 chicks produced. Theoretically, if your pair is split to a mutation, it may not affect chicks in the first nest, but it could affect all the chicks in the second clutch - or a varying percentage in subsequent clutches than what you would otherwise expect. However, the closer you get to producing 100 chicks with the same pair - over the years - eventually the precise numbers predicted will hold true. It is the order in which the mutations appear (not the percentages expected) that may vary. Also, keep in mind that percentage expectations can be reflected in damaged and addled eggs that may never have had the chance to hatch, which may have been that genetic "roll of the dice" you had hoped for. Finally, a very helpful way to find out the background of a cockatiel is to obtain its birth certificate or pedigree record from the breeder. This may not always be possible in all cases, but when obtaining future pets or breeding stock, it may be best to seek out a cockatiel breeder who keeps conscientious records and who close band their birds for accurate record keeping. Such a record would provide an exact birth date, band number for identification purposes, color and background on the parents and possibly earlier generations if known. You would then have the background information to calculate the possibility of whether or not specific mutations could be passed on to offspring produced. |
| SPLITS & GENETICS TESTING Copyright © 2004 Linda S. Rubin All Rights Reserved |
| c.2005 Linda S. Rubin (click thumbnail for larger image). |