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关键词： TGF-β   水产动物   系统进化   生物学功能  

摘要： 转化生长因子-β(Transforming growth factor-β,TGF-β)超家族是一类普遍存在于真核生物中的调控型细胞因子,其家族成员众多,按照其序列结构特征和生物学功能的不同,主要分为TGF-β亚家族、DVR(Decapentaplegic/vg-1-related)亚家族、激活素(Activin)/抑制素(Inhibin)亚家族及其他亚家族等。大量研究显示,TGF-β蛋白超家族成员可调控细胞外基质合成、胚胎发育、器官形成、骨骼再生、组织损伤修复、机体免疫及肿瘤发生等多种生理生化过程。近年来,TGF-β超家族成员在调控水产动物细胞分化、胚胎发育、骨骼形成及免疫应答等生理生化过程中的作用受到人们的广泛关注,本文中综述了近年来水产动物TGF-β超家族成员的系统进化及生物学功能研究进展,为全面系统地了解和掌握该家族成员在水产动物繁殖、发育、生理生化及病理响应等过程中的作用提供线索和参考资料。

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关键词： Evolutionary biology   Modern synthesis   Animal behavior   Population biology   Behavioral ecology   Sociobiology  

摘要： This paper examines the history of animal behavior studies after the synthesis period. Three episodes are considered: the adoption of the theory of natural selection, the mathematization of ideas, and the spread of molecular methods in behavior studies. In these three episodes, students of behavior adopted practices and standards developed in population ecology and population genetics. While they borrowed tools and methods from these fields, they made distinct uses (inclusive fitness method, evolutionary theory of games, emphasis on individual selection) that set them relatively apart and led them to contribute, in their own way, to evolutionary theory. These episodes also highlight some limitations of "conjunction narratives" centered on the relation between a discipline and the modern synthesis. A trend in conjunction narratives is to interpret any development related to evolution in a discipline as an "extension," an "integration," or as a "delayed" synthesis. I here suggest that this can lead to underestimate discontinuities in the history of evolutionary biology.

摘要： All the five species of the genus Thaumatomyia Zenker, 1833 present in Middle Asia have predatory larvae feeding on root aphids. Four species of this genus were recorded in the agrobiocenoses of Uzbekistan and Kyrgyzstan: 2 species (Th. sulcifrons and Th. notata) in the rainfed zone of Uzbekistan, and all the 4 species (Th. glabra, Th. rufa, Th. sulcifrons, and Th. notata) in the beet growing regions of Kyrgyzstan. The remaining species Th. hallandica was recorded only in the mountains of Kyrgyzstan. Adults of Thaumatomyia prefer cereals, alfalfa, sugar beet, umbellifers, and flowering forage herbs. Of the 47 species of root aphids recorded in Uzbekistan and Kyrgyzstan, 38 species develop on cultural plants and weed while 9 species occur on wild shrubs, semi-shrubs, and trees. All the Middle Asian Thaumatomyia species are polyphagous;the larvae of Th. glabra feed on 31, Th. rufa on 22, Th. sulcifrons on 35, Th. notata on 27, and Th. hallandica on 13 species of root aphids. The activity of Thaumatomyia larvae is an important factor of control of the sugar-beet root aphid Pemphigus fuscicornis (Koch) and the bean root aphid Smynthurodes betae Westwood in sugar beet crops in Kyrgyzstan. The efficiency of Thaumatomyia larvae as root aphid control agents was much higher in sugar beet crops than in cereal fields within the rainfed agriculture zone of Uzbekistan. © 2019, Pleiades Publishing, Inc.

关键词： 共轭亚油酸(CLA)   抗炎   免疫调节   脂质代谢   抗氧化  

摘要： 共轭亚油酸(CLA)作为一种天然的新型功能性脂肪酸,具有抗高血压、抗癌、抗糖尿病等生物学特性,其发挥不同作用的主要活性异构体不同。近年来,随着CLA人工合成成本的降低及动物营养领域研究的深入,发现CLA既可抑制促炎因子的表达和产生,促进抑炎因子的产生,达到抗炎的效果;又可调控淋巴细胞的增殖和分化、巨噬细胞的活性、促进抗体合成,调节机体体液免疫和细胞免疫,进而增强动物免疫力;CLA还可调节多种核转录因子的表达,影响脂肪酸的摄取和氧化及脂质的合成代谢,从而降低体脂沉积,提高肌内脂肪含量,改变脂肪酸组成,改善肉品质等。因此CLA在畜牧业生产中具有潜在的应用价值和广阔的市场前景。作者主要介绍了CLA在抗炎、免疫功能、脂质代谢和抗氧化等方面的作用,综述了CLA的生物学功能及其在动物生产上的应用研究进展。此外,还探讨了CLA作为饲料添加剂,其合成纯度,在不同种类动物、不同年龄阶段的最适添加量、饲喂方式等问题,旨在为其在动物生产中的合理应用提供理论参考。

关键词： 白藜芦醇   抗氧化   抗炎   肠道  

摘要： 白藜芦醇是一种含有茋类结构的天然非黄酮类多酚类化合物,具有多种生物学功能:可抑制和清除体内过量的自由基,激活机体抗氧化酶系统,发挥抗氧化功能;通过调控一系列炎症或抗炎通路,降低机体内炎性因子表达,降低炎症反应。白藜芦醇还具有调节糖脂代谢、保护心血管、抗癌、抗病毒等重要生物学功能,且具有安全高效、无残留、不产生耐药性的优点,在动物生产中的应用具有广阔的应用前景。动物试验表明,白藜芦醇能提高肉鸡平均日增重、平均采食量,降低料重比;提高育肥猪肉品质,增加背最长肌pH 24 h、红度、粗蛋白质和肌红蛋白含量,还可降低24 h后肌肉亮度、剪切力、滴水损失、背膘厚度;提高动物机体内抗氧化酶活性;降低炎性因子的产生,增强机体免疫;改善肠道菌群组成和肠道黏膜形态;抑制癌细胞的生成。本试验针对白藜芦醇生物学特性、生理功能及其在畜禽生产中的应用现状进行综述,旨在为其在畜禽生产中的应用提供参考依据。

关键词： PCR   semen   selective breeding   genotyping  

摘要： The laboratory exercise described here aims to provide a relevant context for learning basic DNA techniques in an introductory animal science course at tertiary level. In two 4-hr laboratory sessions, students assess the suitability of bulls for inclusion in a gene-assisted selection program for A2 beta-casein by genotyping commercial bull sperm. Sperm cells are lysed to extract the genomic DNA, and PCR with primers for the beta-casein gene is performed. Using the principle of amplification-created restriction sites, restriction digestion with TaqI can be used to distinguish between the A1 allele and the A2 allele of the gene. Cut PCR amplicons are separated by gel electrophoresis to evaluate the genotype of each bull. Students then write a diagnostic report with accompanying letter to their fictional client, explaining the DNA test, and interpreting the results. (c) 2019 International Union of Biochemistry and Molecular Biology, 1-4, 2019.

关键词： Amphibians   Tadpoles   Rainforests   Ribosomal RNA   Conservation science   DNA barcoding   Species diversity   Frogs  

摘要： Amphibians are the focus of a recent debate and public attention owing to the global decline in their populations worldwide. Amphibians are one of the most threatened and poorly known groups of vertebrates in several geographic areas, even though they play a central role in their own ecosystems. At different levels, amphibians make their contribution to proper ecosystem functioning. They act as regulators of the food web and nutrient cycling, and they also provide several valuable ecosystem services, e.g., as a food source and as animal models for lab research. In this sense, it seems clear that the maintenance of amphibian diversity should be one of the major goals for the several countries where their population decline is observed. However, we are still struggling with the very first step of this process, i.e., the correct identification of the amphibian species diversity. Over the past few decades, research on molecular identification of amphibians using DNA barcoding has encountered some difficulties related to high variability in the mitochondrial genome of amphibians, and a research gap is noticeable in the literature. We herein evaluated both COI and 16S rRNA mitochondrial genes for the molecular identification of frogs and tadpoles in a large fragment of the South American Atlantic Rainforest in Rio de Janeiro, Brazil. Our results suggest that both COI and 16S rRNA are informative markers for the molecular identification of the amphibian specimens with all specimens unambiguously identified at the species level. We also made publicly available 12 new sequences of Atlantic Rainforest amphibian species for the first time, and we discussed some conservation issues related to amphibians within the Atlantic Rainforest domains in the state of Rio de Janeiro, Brazil.