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British Poultry Science Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/cbps20
Further studies on the inheritance of the marbled chickdown phenotype of the domestic fowl W. C. Carefoot
a
a
’Cliveden’, Sandy Bank , Chipping, Preston, PR3 2GA, England Published online: 08 Nov 2007.
To cite this article: W. C. Carefoot (1992) Further studies on the inheritance of the marbled chickdown phenotype of the domestic fowl, British Poultry Science, 33:4, 889-891, DOI: 10.1080/00071669208417531 To link to this article: http://dx.doi.org/10.1080/00071669208417531
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/ page/terms-and-conditions
British Poultry Science (1992) 33: 889-891
SHORT COMMUNICATION
FURTHER STUDIES ON THE INHERITANCE OF THE MARBLED CHICKDOWN PHENOTYPE OF THE DOMESTIC FOWL W. C. CAREFOOT 'Cliveden', Sandy Bank, Chipping, Preston PR3 2GA, England
Downloaded by [] at 01:34 16 May 2015
Received for publication 15th October 1991
Abstract 1. An investigation was conducted among the progeny from crosses between Birchen Modern Game and Silver Sebright bantams into the inheritance of the marbled chickdown phenotype of the latter. 2. The marbled chickdown phenotype has been shown to depend upon homozygocity of both the birchen allele £R at the E-locus and the eumelanin restrictor gene Db. However, all stock used to establish this result were also homozygous for the linked eumelanin intensifier melanotic Ml and the pattern gene Pg, therefore yielding no information on the roles of Ml or Pg in the marbled chickdown phenotype. 3. Examination of the F2 generation both of chickdown and of adult plumage demonstrated the marbled chickdown to be homozygous ER (Db-Pg) with Ml dosage having an effect on adult plumage.
INTRODUCTION
The genotypes of the Silver-Spangled Hamburgh and Sebright bantams have been shown by Carefoot (1992) to depend upon homozygocity of EK co+ {Db—Ml—Pg) and £R Co (Db—Ml—Pg), respectively, where £R is the birchen allele at the E-locus and Co, Db, Ml and Pg are, respectively, the eumelanin restrictors, Columbian and dark-brown Columbian, the eumelanin extension melanotic and the pattern gene. Both breeds have marbled chickdowns which Carefoot (1992) demonstrated depended upon ER/ER Db/Db. However, in tests to establish this dependence all stock used were also homozygous Ml—Pg. Consequently, no conclusion was possible as to whether the marbled chickdown phenotype also depends on Ml, Pg or both. A mating was, therefore, set up between Birchen Modern Game and Silver-Sebright bantams to investigate the role of Ml and Pg in the marbled-chickdown phenotype. 889
890
W. C. CAREFOOT
Downloaded by [] at 01:34 16 May 2015
METHODS AND RESULTS
The Silver Sebright female and the Birchen Modern Game male to which she was mated, were typical of their respective breeds and, therefore, their genotypes were presumed to be ER Co (Db—Ml—Pg) and ER co+ (db+—ml+—pg+) homozygotes, respectively. The mating yielded 11 chicks: 4 males and 7 females, all of which had black chickdowns with variable brown heads. Two of the males and 5 females were selected at random and mated inter se to produce an F2 generation of 36 chicks. Classification of the F2 was firstly by chickdown into 25 black with variable brown heads, 4 with narrow back stripes and 7 marbled. As adults the marbled chicks were all patterned, whilst their adult phenotypes included transversely barred, lace-tailed laced, spangled and various intermediates. The chicks with narrow back stripes were classified as (Db—Pg)/(db+—Pg) by their similarity to those of that phenotype recorded by Carefoot (1992). The marbled chickdown segregants developed into patterned adults, and were classified as (Db—Pg)/(Db—Pg), variations in patterns being attributed to Ml and/or Co dosage. Therefore, the marbled-chickdown phenotype does not depend on Ml. If ER and Db when homozygous were the only genes required to produce the marbled chickdown, the three chickdown phenotypes would segregate in a 1:2:1 ratio. The observed segregation varied highly significantly (#2 = 39-78, 2DF, P
British Poultry Science Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/cbps20
Further studies on the inheritance of the marbled chickdown phenotype of the domestic fowl W. C. Carefoot
a
a
’Cliveden’, Sandy Bank , Chipping, Preston, PR3 2GA, England Published online: 08 Nov 2007.
To cite this article: W. C. Carefoot (1992) Further studies on the inheritance of the marbled chickdown phenotype of the domestic fowl, British Poultry Science, 33:4, 889-891, DOI: 10.1080/00071669208417531 To link to this article: http://dx.doi.org/10.1080/00071669208417531
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http://www.tandfonline.com/ page/terms-and-conditions
British Poultry Science (1992) 33: 889-891
SHORT COMMUNICATION
FURTHER STUDIES ON THE INHERITANCE OF THE MARBLED CHICKDOWN PHENOTYPE OF THE DOMESTIC FOWL W. C. CAREFOOT 'Cliveden', Sandy Bank, Chipping, Preston PR3 2GA, England
Downloaded by [] at 01:34 16 May 2015
Received for publication 15th October 1991
Abstract 1. An investigation was conducted among the progeny from crosses between Birchen Modern Game and Silver Sebright bantams into the inheritance of the marbled chickdown phenotype of the latter. 2. The marbled chickdown phenotype has been shown to depend upon homozygocity of both the birchen allele £R at the E-locus and the eumelanin restrictor gene Db. However, all stock used to establish this result were also homozygous for the linked eumelanin intensifier melanotic Ml and the pattern gene Pg, therefore yielding no information on the roles of Ml or Pg in the marbled chickdown phenotype. 3. Examination of the F2 generation both of chickdown and of adult plumage demonstrated the marbled chickdown to be homozygous ER (Db-Pg) with Ml dosage having an effect on adult plumage.
INTRODUCTION
The genotypes of the Silver-Spangled Hamburgh and Sebright bantams have been shown by Carefoot (1992) to depend upon homozygocity of EK co+ {Db—Ml—Pg) and £R Co (Db—Ml—Pg), respectively, where £R is the birchen allele at the E-locus and Co, Db, Ml and Pg are, respectively, the eumelanin restrictors, Columbian and dark-brown Columbian, the eumelanin extension melanotic and the pattern gene. Both breeds have marbled chickdowns which Carefoot (1992) demonstrated depended upon ER/ER Db/Db. However, in tests to establish this dependence all stock used were also homozygous Ml—Pg. Consequently, no conclusion was possible as to whether the marbled chickdown phenotype also depends on Ml, Pg or both. A mating was, therefore, set up between Birchen Modern Game and Silver-Sebright bantams to investigate the role of Ml and Pg in the marbled-chickdown phenotype. 889
890
W. C. CAREFOOT
Downloaded by [] at 01:34 16 May 2015
METHODS AND RESULTS
The Silver Sebright female and the Birchen Modern Game male to which she was mated, were typical of their respective breeds and, therefore, their genotypes were presumed to be ER Co (Db—Ml—Pg) and ER co+ (db+—ml+—pg+) homozygotes, respectively. The mating yielded 11 chicks: 4 males and 7 females, all of which had black chickdowns with variable brown heads. Two of the males and 5 females were selected at random and mated inter se to produce an F2 generation of 36 chicks. Classification of the F2 was firstly by chickdown into 25 black with variable brown heads, 4 with narrow back stripes and 7 marbled. As adults the marbled chicks were all patterned, whilst their adult phenotypes included transversely barred, lace-tailed laced, spangled and various intermediates. The chicks with narrow back stripes were classified as (Db—Pg)/(db+—Pg) by their similarity to those of that phenotype recorded by Carefoot (1992). The marbled chickdown segregants developed into patterned adults, and were classified as (Db—Pg)/(Db—Pg), variations in patterns being attributed to Ml and/or Co dosage. Therefore, the marbled-chickdown phenotype does not depend on Ml. If ER and Db when homozygous were the only genes required to produce the marbled chickdown, the three chickdown phenotypes would segregate in a 1:2:1 ratio. The observed segregation varied highly significantly (#2 = 39-78, 2DF, P
