English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

vasive source of DNA for humans (Feigelson et al. 2001), experimental animals (Zimmerman et al. 2000), livestock (Kwon et al. 1993), and wild primates (Hashimoto et al. 1996), but have not been used for wild birds. Blood is the most commonly used source of DNA for avian molecular ecological studies because safe and effective sampling techniques have been well-developed (reviewed in Wingfield 1999), hence other non-invasive methods have not been deemed necessary. In the case of the Ryukyu Robin Erithacus komadori, endemic only to southwestern Japan (Kawaji & Higuchi 1989), however, blood sampling is difficult. Because of its limited distribution and the steep population declines on some islands, it has been designated as a “national natural treasure” and “national endangered species of wild fauna and flora” of Japan. Consequently, both the Kagoshima prefectural government and the national agency for cultural affairs are against taking blood samples from robins, especially from nestlings, for political and cultural reasons. However, in order to reveal sex-related mortality and dispersal distances of sexually monomorphic fledglings, molecular sexing is needed (Seki 2002). Here I report the results of molecular sexing of adult robins using DNA extracted from buccal cells, comparing them with those from blood, and examine the reliability of buccal cells as a source of DNA for avian sexing. Samples of both buccal cells and blood were obtained from 20 male and 20 female adult Ryukyu Robins, that had been previously sexed based on morphological characteristics. Robins were captured (under license by mist-net) during the breeding season, from 15 April to 30 June 2002, on Nakanoshima Island, Kagoshima, Japan. Buccal cells were collected by rolling cotton swabs against the inside of each robins’ mouth and throat five times. Each swab was put into a microtube and soaked in 1 ml of preservation buffer (150 mM NaCl, 10 mM Tris-HCl pH 8.0, 10 mM EDTA), and kept at room temperature during the one week it took to transport them to the laboratory, where they were stored at 5°C for up to one month (see also Appendix 1 for longer preservation). After adding 10 m l of 10%-SDS, the samples were digested with proteinase K (5 m l of 20mg/ml) at 55°C for one hour and an additional 16 hours at 37°C. DNA was then extracted by the conventional phenol/chloroform method. Up to 30 m l of blood samples were obtained by brachial vein puncture and no ill effects were recorded. Blood samples were stored in GenTLE solution I (Takara) at room temperature and DNA was extracted using an extraction kit (QIAamp DNA Blood Mini Kit, QIAGEN) within 10 days of sampling. The sex of each individual was determined by length polymorphism at the chromo-helicase-DNAbinding (CHD) gene, using Ellegren & Fridolfsson’s (1997) primer set 3007F (5 -TACATACAGGCTCTACTCCT-3 ) and 3112R (5 -CCCCTTCAGGTTCTTTAAAA-3 ), following the methods used by Fridolfsson & Ellegren (1999). All PCR reactions were performed in 25 m l volumes on a Perkin Elmer 9600 Thermal Cycler, using Taq DNA polymerase (Takara Taq, Takara). Each reaction mixture contained 0.625 unit of Taq, 200 mM dNTPs, 20 mM Tris-HCl pH 8.0, 50 mM KCl, 2 mM MgCl2, 5 pmol of primers. The thermal profile comprised an initial denaturing step of 94°C for two minutes, followed by a “touch-down” scheme where the annealing temperature was lowered by 1°C per cycle, starting from 60°C until a temperature of 50°C was reached. Then 35 additional cycles were run at a constant annealing temperature of 50°C. Denaturation was at 94°C for Molecular sexing of individual Ryukyu Robins Erithacus komadori using buccal cells as a non-invasive source of DNA