Review of genetic diversity and breed identification of black-bone silky fowl / 中国中药杂志

Black-bone silky fowl, sweet, pungent, and hot-natured, is one of the valuable domesticated birds with special economic value in China's genebank of poultry breed, which has a long history of medicinal and edible uses. It has the effects of tonifying liver and kidney, replenishing Qi and blood, nourishing yin, clearing heat, regulating menstruation, invigorating spleen, and securing essence. Therefore, it has remarkable efficacy of enhancing physical strength, tonifying blood, and treating diabetes and gynecological diseases. Various local black-bone silky fowl breeds have been generated due to the differences in environmental conditions, breed selection, and rearing conditions in different areas of China, which are mainly concentrated in Taihe, Wan'an, and Ji'an in Jiangxi province and Putian, Jinjiang, and Yongchun in Fujian province. The indigenous chicken breeds in China have different body sizes, appearance, coat colors, etc. The complex lineages lead to extremely unstable genetic traits. The diverse breeds similar in appearance result in the confusion in the market of silky fowl breeds. With the rapid development of molecular biological technology, the genetics of black-bone silky fowls has been intensively studied. This article reviews the research progress of the germplasm resources, genetic diversity, and breed identification of black-bone silky fowl in China at the morphology, chromosome, protein, and DNA levels. Further, it introduces the principles, application status, and limitations of DNA markers such as mitochondrial DNA, microsatellite markers, and SNPs. This review provides a theoretical basis for the mining of elite trait genes and the protection and utilization of local black-bone silky fowl germplasm resources in China.

Macromolecular array patterns of silk gland secretion in social Hymenoptera larvae

The cocoon, produced by most holometabolous insects, is built with silk that is usually produced by the larval salivary gland. Although this silk has been widely studied in the Lepidoptera, its composition and macromolecular arrangement remains unknown in the Hymenoptera. The macromolecular array patterns of the silk in the larval salivary gland of some meliponids, wasps, and ants were analyzed with polarized-light microscopy, and they were compared with those of Bombyx mori (Lepidoptera). There is a birefringent secretion in the glandular lumen of all larvae, due to filamentous structural proteins that display anisotropy. The silk in the distal, middle and proximal regions of the secretory portion of Formicidae and Vespidae glands presented a lattice optical pattern. We found a different pattern in the middle secretory portion of the Meliponini, with a zigzag rather than a lattice pattern. This indicates that the biopolymer fibers begin their macromolecular reorganization at this glandular region, different from the Formicidae and the Vespidae, in which the zigzag optical pattern was only found at the lateral duct. Probably, the mechanism of silk production in the Hymenoptera is a characteristic inherited from a common ancestor of Vespoidea and Sphecoidea; the alterations in the pattern observed in the Meliponini could be a derived characteristic in the Hymenoptera. We found no similarity in the macromolecular reorganization patterns of the silk between the Hymenoptera species and the silkworm.