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Urano K.,Kyoto University | Yamada T.,Kyoto University | Taniguchi Y.,Kyoto University | Iwaisaki H.,Kyoto University | And 3 more authors.
Animal Science Journal | Year: 2011

The Japanese Crested Ibis Nipponia nippon is a critically threatened bird. The post-hatch eggs of the current captive population of this species on Sado Island have been stored at room temperature for the long-term. In this study, we investigated the suitability of the vascularized chorioallantois membrane from the eggs as a non-invasive DNA source. Using microsatellite loci developed for the Japanese Crested Ibis, we performed three experiments for comparison of genotypes obtained among DNA. First, DNA from five different sites of the identical membrane showed the same genotypes at either of two loci examined. Second, DNA from the membrane of each full-sibling birds and blood of their parents showed the genotypes that were consistent with Mendelian parent-offspring relationships at any of eight loci examined. Third, DNA from the membrane and blood of the same bird showed the matched genotypes at any of eight loci examined. These results indicate that the vascularized chorioallantois membrane from post-hatch eggs stored at room temperature for the long- term can be used as a reliable DNA source of offspring that had hatched from the egg. This study will promote a molecular genetics study on genetic diversity of the current captive Japanese Crested Ibis population on Sado Island. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science. Source


Tsubono K.,Kyoto University | Taniguchi Y.,Kyoto University | Matsuda H.,Kyoto University | Homma K.,Niigata University | And 3 more authors.
Animal Science Journal | Year: 2014

Japanese population of the Japanese crested ibis Nipponia nippon was founded by five individuals gifted from the People's Republic of China. In order to exactly evaluate genetic structure, we first performed development of novel genetic makers using 89 microsatellite primer pairs of related species for cross-amplification. Of these, only three primer pairs were useful for the genetic markers. Additionally, we sequenced allelic PCR products of these three markers together with 10 markers previously identified. Most markers showed typical microsatellite repeat units, but two markers were not simple microsatellites. Moreover, over half of the markers did not have the same repeat units as those of the original species. These results suggested that development of novel genetic markers in this population by cross-amplification is not efficient, partly because of low genetic diversity. Furthermore, the cluster analysis by STRUCTURE program using 17 markers showed that the five founders were divided into two clusters. However, the genetic relationships among the founders indicated by the clustering seemed to be questionable, because the analysis relied largely on a small number of triallelic markers, in spite of the addition of the three useful markers. Therefore, more efficient methods for identifying large numbers of single nucleotide polymorphisms are desirable. © 2013 Japanese Society of Animal Science. Source


Wajiki Y.,Chuo Livestock Hygiene Service Center | Kaneko Y.,Sado Japanese crested ibis Conservation Center | Sugiyama T.,Niigata University | Yamada T.,Niigata University | Iwaisaki H.,Kyoto University
Journal of Poultry Science | Year: 2016

The Japanese captive population of Japanese crested ibis (Nipponia nippon) was established using 5 founders derived from the Chinese captive population. Its size has increased rapidly, and the maintenance phase is about to start. Thus, this study was designed to perform genetic analyses in this population with pedigree information, considering the adoption of mean kinship strategy as the breeding strategy suited to the maintenance phase. Because the relationships among the 5 founders were unknown, different assumptions were set up ranging from 0 to 0.25 of kinship coefficients between the 5 founders. Assuming that the 5 founders were non-inbred in all the assumptions, the results showed that the gene diversity and the mean inbreeding coefficient would fluctuate largely from ∼65% to ∼82% and from ∼0.07 to ∼0.29, respectively. Moreover, the genetic importance of individuals based on mean kinship shifted largely. This study suggested that the Japanese captive population had low gene diversity and high mean inbreeding coefficient even under the assumption that the 5 founders were unrelated and non-inbred. In addition, the study also suggested that it became more effective to analyze the genetic status and to introduce mean kinship strategy into this population with more credible molecular evaluation of the relationships among founders. © 2016, Japan Poultry Science Association. Source


Kaneko K.,Niigata University | Uematsu E.,Niigata University | Takahashi Y.,Niigata University | Tong B.,Niigata University | And 9 more authors.
Reproduction in Domestic Animals | Year: 2013

Contents: This study aimed to develop a polymerase chain reaction (PCR)-based sexing and effective semen collection methods for black-headed and straw-necked ibis species. However, most birds are not sexually dimorphic, that is, the sexes appear similar. Therefore, the gender should be determined before semen collection. DNA was extracted from the blood samples of 11 black-headed and 4 straw-necked ibis. The sex was determined after PCR amplification of the EE0.6 region of W-chromosome. The PCR products were separated using gel electrophoresis. A single band indicated the presence of the EE0.6 region and that the individual was a female, while no band indicated that the individual was a male. Further, the single bands from seven specimens were amplified. Semen collection was performed by massage or a combination of massage with electro-ejaculation and was attempted during all four seasons. The semen was successfully collected in March from male straw-necked ibis using the massage method. Limited motility, viability and concentration of straw-necked ibis sperm were observed. The sperm length was 180 μm and that of the nucleus was 30 μm with acrosome located at the tip of the nucleus. Thus, the PCR-based sexing proved to be an accurate molecular sexing method for black-headed and straw-necked ibis. Furthermore, we successfully collected semen and observed the stained sperm nucleus and acrosome of the straw-necked ibis sperm. We propose that the use of this PCR methodology can be applied as a routine method for sex determination and semen collection in ibis species for future ecological research. However, considering our limited success, further studies on semen collection method are required. © 2013 Blackwell Verlag GmbH. Source


Taniguchi Y.,Kyoto University | Matsumoto K.,Kyoto University | Matsuda H.,Kyoto University | Yamada T.,Niigata University | And 5 more authors.
PLoS ONE | Year: 2014

The major histocompatibility complex (MHC) is a highly polymorphic genomic region that plays a central role in the immune system. Despite its functional consistency, the genomic structure of the MHC differs substantially among organisms. In birds, the MHC-B structures of Galliformes, including chickens, have been well characterized, but information about other avian MHCs remains sparse. The Japanese Crested Ibis (Nipponia nippon, Pelecaniformes) is an internationally conserved, critically threatened species. The current Japanese population of N. nippon originates from only five founders; thus, understanding the genetic diversity among these founders is critical for effective population management. Because of its high polymorphism and importance for disease resistance and other functions, the MHC has been an important focus in the conservation of endangered species. Here, we report the structure and polymorphism of the Japanese Crested Ibis MHC class II region. Screening of genomic libraries allowed the construction of three contigs representing different haplotypes of MHC class II regions. Characterization of genomic clones revealed that the MHC class II genomic structure of N. nippon was largely different from that of chicken. A pair of MHC-IIA and -IIB genes was arranged head-to-head between the COL11A2 and BRD2 genes. Gene order in N. nippon was more similar to that in humans than to that in chicken. The three haplotypes contained one to three copies of MHC-IIA/IIB gene pairs. Genotyping of the MHC class II region detected only three haplotypes among the five founders, suggesting that the genetic diversity of the current Japanese Crested Ibis population is extremely low. The structure of the MHC class II region presented here provides valuable insight for future studies on the evolution of the avian MHC and for conservation of the Japanese Crested Ibis. © 2014 Taniguchi et al. Source

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