ABSTRACT A type of feather structure abnormality in Japanese quail resulting from the ... Porcupine quail have poor egg production, lower fertility, and higher ...
"Porcupine": A Feather Structure Mutation in Japanese Quail J. E. FULTON, C. W. ROBERTS, 1 and K. M. CHENG
Avian Genetics Laboratory, Department of Poultry Science, University of British Columbia, Vancouver, British Columbia, Canada V6T 2A2 (Received for publication May 7, 1981) ABSTRACT A type of feather structure abnormality in Japanese quail resulting from the failure of barbs to uncoil was found to be controlled by a single autosomal recessive gene, pc (porcupine). The mutation was first identified in two birds from a population homozygous for white plumage color. Porcupine quail have poor egg production, lower fertility, and higher embryonic and chick mortality compared to wildtype or heterozygotes. (Key words: Japanese quail, mutation, feather, recessive, autosomal, amino acids) 1982 Poultry Science 61:429-433
In March of 1977, 2 birds with abnormal feathers were found in consecutive routine reproductions of a population of white Japanese quail (described by Roberts et al., 1978). The shafts of the feathers of these individuals appeared normal, but the barbs failed to uncoil, giving the feathers the appearance of porcupine quills (See Fig. 2; Fig. 1 shows quail with normal feathers). Gross examination under light microscope showed that both distal and proximal barbules were present and appeared normal. The affected feathers were particularly noticeable on the wings (i.e., the primary and secondary remiges) and also on the back. As the birds grew older, the barbs partially uncoiled so that the trait could be clearly observed only on the wings. A mutation with a similar phenotype was found in the pigeon, first in 1909 and again in 1927 (Cole and Hawkins, 1930), and was named "porcupine" (p). Genetic tests seemed to indicate that porcupine in pigeons was recessive and inherited autosomally. However, due to very poor reproduction in porcupine pigeons, sample sizes for the tests were small. Waters (1967) reported a mutation which caused abnormal feather development in an inbred line of chickens. The mutant chicks could be discerned at hatch, and as adults they were similar in appearance to that described for porcupine pigeons. This mutant was also called
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Deceased January 11, 1980.
porcupine (pc). Reproduction in porcupine chickens and survival of porcupine chicks was also very poor, and the author attributed this to the abnormal feathers. Because of the similarity in appearance between the abnormal quail and the previously described mutants in pigeons and chickens, the trait in quail was also called porcupine and breeding tests were designed to determine the inheritance of the trait. Results of these tests are presented and discussed in this paper.
MATERIALS AND METHODS
The first porcupine quail was a male and was mated to 4 normal females from the white population. The resulting Fj birds were intermated to produce F 2 progeny. The 2nd porcupine quail, found at 11 days of age, was also a male and was mated to 2 females from the white population. Further testing of the first porcupine male was discontinued because of poor reproduction of his progeny. All subsequent breeding and the resultant porcupine line were derived from the second male. During the following four generations, test matings were set up to determine the inheritance of the porcupine trait. Porcupine progeny that segregated from inter se ¥x (half-sib) matings were intermated and were also outcrossed to the white population to obtain more heterozygotes. With the increased number of porcupine birds and heterozygotes, further matings of heterozygotes X heterozygotes and reciprocal porcupine X heterozygotes were set up. With the exception of the F t matings, no
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INTRODUCTION
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FIG. 1. Japanese quail (Pc+/Pc+) feathering.
FULTON ET AL.
with normal
Data from the first three generations suggested a deficiency of porcupine chicks in matings where the progeny should be segregating for wild-type and mutant phenotypes. In generation four, 24 porcupine males were individually mated to both a normal white female (wild-type) and a porcupine female to determine if there was differential embryonic and chick mortality between porcupine and wild-type (WT) chicks. Eggs from each female were identified according to their shape and color (Jones et al., 1964).
with quill-like
RESULTS AND DISCUSSION Only 1 of the 4 females mated to the first porcupine male produced fertile eggs. Of the 29 eggs from this female, 28 were fertile but only 11 chicks hatched. All chicks were phenotypically normal. Assuming simple recessive inheritance, matings between fr\ individuals were expected to produce a 3:1 ratio of normal:mutant progeny, but no chicks with the mutant phenotype were found (35 WT:0 porcupine, \2 = 11.2, P
