| COLOR DEPIGMENTATION IN COCKATIELS Copyright © 2004-2007 Linda S. Rubin All Rights Reserved (All cockatiel photos this page c. Laurie Bethea) |
| 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 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! |
Copyright 2007 Linda S. Rubin
| Multiple Bird Households by Linda S. Rubin |
| Series by Linda S. Rubin |
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| Q. Hi Linda, My adult Normal Grey cockatiel, Raven, has feathers on his tail and the undersides of his wings that are turning white. I wish I could figure out why. Here is a cute picture of Raven showing off below and another of a close up of his tail feathers. Thanks, Laurie A. Hi Laurie, Your question and two pictures are very interesting because I've written about this phenonemon in one of my earlier booklets that deals specifically with color depigmentation. Some of the research I refer to in includes inferences from a study conducted some years back by Tom Roudybush. In essence, Tom Roudybush's findings on cockatiels with depigmented feathers (grey feathers appearing white) indicated either a riboflavin (vitamin B2), or choline (vitamin B complex) deficiency in the diet. The article I wrote was originally published in full in the January/February 1990 Journal and includes a photo of a cockatiel with a more extensive depigmentation to its flight and tail feathers. For your convenience, I am reprinting the paragraphs from the article to help you. You may wish to ask your veterinarian to aid you in formulating an effective vitamin mix or find out why your bird may not be metabolizing these nutrients at this time should testing prove that your bird is deficient (presumably, a CBC blood panel and chemistry profile should be helpful). Here then, is the section of my article commenting on the research: "In the past, it has been found that, in poultry, lysine deprivation can depigment feathers causing them to appear white, with flight and tail feathers being those most commonly affected. To the contrary, lysine deprivation in cockatiels did NOT produce any depigmentation as was expected. Further studies on cockatiels by team members Debbie Nearenberg with the manipulation of riboflavin (vitamin B2), which normally results in curly toe paralysis in poultry, instead produced unusual results. It was found that deprivation of riboflavin did not produce the expected curly toe paralysis, but DID result in depigmentation in the cockatiels tested, producing white feathers! Furthermore, the team investigated a study with choline deficiency, which in poultry produces perosis (i.e., a slippage of the ligament of the hock joint). Interestingly, choline deficiency resulted in the loss of melanin (grey) pigment in both the flight and tail feathers in 30 to 40 percent of the cockatiels tested. The conclusion: applying signs of nutritional deficiencies from studies in poultry to cockatiels, and perhaps other cage birds, may not apply. A riboflavin (vitamin B2) or choline deficiency in cockatiels may look like a lysine deficiency in poultry." It appears your bird has lost some pigment, although it is not as severe as the photo that is included in the article I contributed in the Jan/Feb 1990 Journal. I'd also be interested to know the follow up to Raven's treatment, if any, or whether the feathers returned to normal coloration. Good luck, Linda S. Rubin |
