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Abstract Background Effective conservation and utilization of farm animals are fundamental for realizing sustainable increases in food production. In situ and ex situ conservation are the two main strategies that are currently used to protect the genetic integrity of Chinese domestic chicken breeds. However, genomic diversity and population structure have not been compared in these conserved populations. Results Three hundred and sixty-one individuals from three Chinese domestic chicken breeds were collected from populations conserved in situ and ex situ and genotyped using genotyping-by-sequencing (GBS). First, we used different parameters based on heterozygosity, genomic inbreeding, and linkage disequilibrium to estimate the genomic diversity of these populations, and applied principal component analysis (PCA), neighbor-joining tree, and ADMIXTURE to analyze population structure. We found that the small ex situ conserved populations, which have been maintained in controlled environments, retained less genetic diversity than the in situ conserved populations. In addition, genetic differentiation was detected between the in situ and ex situ conserved populations of the same breed. Next, we analyzed signatures of selection using three statistical methods (fixation index (FST), nucleotide diversity (Pi), and cross-population extended haplotype homozygosity (XP-EHH) to study the genetic footprints that underlie the differentiation between in situ and ex situ conserved populations. We concluded that, in these small populations, differentiation might be caused by genetic drift or by mutations from the original populations. The differentiation observed in the population of Beijing You chicken probably reflects adaptation to environmental changes in temperature and humidity that the animals faced when they were moved from their place of origin to the new site for ex situ conservation. Conclusions Conservation programs of three Chinese domestic chicken breeds have maintained their genomic diversity to a sustainable degree. The small ex situ conserved populations, which are maintained in controlled environments, retain less genetic diversity than populations conserved in situ. In addition, the transfer of populations from their place of origin to another site for conservation purposes results in genetic differentiation, which may be caused by genetic drift or adaptation. This study provides a basis for further optimization of in situ and ex situ conservation programs for domestic chicken breeds in China.

The Macrophya zhaoae group is reviewed and five species are recognized in China, including a newly described species, M. lishuii Li, Liu & Wei sp. nov. from Zhejiang Province, and four previously known species, M. hainanensis Wei & Nie, 2002, M. minutitheca Wei & Nie, 2002, M. nigrospuralina Wei, 2005 and M. zhaoae Wei, 1997. A key to all Chinese species and a distribution map of the M. zhaoae group in China are provided.

Spiroindoles are key scaffolds in a large number of natural products, pharmaceuticals, and agrochemicals. Selective C–H activation has emerged as a powerful synthetic approach to streamline the synthesis of substituted spiroindoles. To date, various 2- and 3-indolyl-tethered aza-spiro-centers have been successfully achieved via C–H activation. However, introduction of spiro-containing systems onto the benzenoid core of indole still remains challenging. Herein, a method of Rh(III)-catalyzed selective C7-H activation/cyclization of indole with maleimide to afford novel spiroindole derivatives is reported, which incorporate both succinimide and spirocycle into indole unit. Gram-scale synthesis demonstrates the utility of this protocol, further modification via click chemistry offered a novel scaffold as a versatile spiro linker. [ABSTRACT FROM AUTHOR]

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