种公禽繁殖系统对光要素的应答机制研究进展

光照是生物体重要的生活环境因素之一。禽类具有优越的感光机能,光线通过其光感受器被感知,并转变为生物学信号,从而对生长发育、繁殖和行为等方面产生影响。在现代养禽业中,人工优化光照环境已成为提高动物生产性能的一项重要手段。近年来,随着种用母鸡笼养、人工授精技术的广泛应用及精液处理、包装和存储技术的发展,在家禽养殖中,也逐步将种公禽单独饲养。研究光照对种公禽繁殖性能的影响,一方面可以进一步解析种公禽繁殖系统对光要素的生物应答机制,另一方面可为生产中采用精细化的光照条件提高种公禽繁殖效率提供科学依据。笔者就禽类的光感受器,参与光-性信号传导的激素,以及光照节律、光照强度和光波长对种公禽性成熟和繁殖性能的影响等方面的研究进展进行综述,以期为其在生产中的应用奠定基础。     

家禽附睾功能及其对睾丸后精子成熟调控机制研究进展

睾丸内的精子虽已成型,但仍需要在附睾中经过一系列修饰,使形态结构和功能进一步变化,才能获得运动和受精能力,这个过程即精子成熟。与哺乳动物相比,家禽附睾发生一定退化,但近年来越来越多的研究表明家禽附睾对精子成熟有调控作用。在畜禽良种繁育体系中,精子功能直接与繁殖效率高度关联,影响制种成本和养殖效益。因此,挖掘家禽精子功能和精液品质的调控机制,对于改善雄性不育、建立家禽繁殖性能的选育方法和改良技术具有重要的应用价值。本文将对家禽附睾功能及其对精子睾丸后成熟的作用机制研究进展进行综述,以期为进一步研究附睾的家禽繁殖性能调控机制奠定基础。     

三价铬对畜禽繁殖性能的影响及其作用机制

三价铬是动物需要的微量元素之一,具有缓解应激、改善肉质的功能,对动物的繁殖也有重要作用。铬通过缓解应激对繁殖的损伤和调节机体的内分泌等方面影响畜禽的繁殖性能。本文就铬对畜禽繁殖性能的影响及其可能的机制作一综述,以期为三价铬在种用畜禽上的合理应用提供理论支持。     

氨气影响动物健康和生产性能的机理

随着畜禽养殖数量和规模不断扩大,养殖环境趋于恶化。畜禽对空气质量敏感,空气质量与发病率直接相关。氨气（NH₃）是影响动物健康及生产最主要的环境有害气体之一。动物长期暴露于氨气中会诱发呼吸系统疾病,引起神经功能障碍,降低生殖能力和生长能力。本文总结了氨气影响动物健康和生产性能的机制。     

Effects of artificial supplemental light on the reproductive season of geese kept in open houses

1. New lighting programmes were designed to change the pattern of goose reproduction, based on the response of predictable avian photoperiodic stimulation. The objective of this study was to evaluate the efficiency of a long photoperiod of 20L on shifting goose reproduction to the non-breeding season in an open housing system. 2. Eighty mature White Roman geese were randomly allocated into 4 groups (male:female = 1:4). The supplemental lighting programmes with a daily photoperiod of 20 h were initiated on 22 November and withdrawn when 90% of geese were moulting in the treatment groups. Artificial light intensities of 220, 120 and 20 lux were provided to experimental groups A, B and C, respectively. In contrast, the geese in control group D were kept under natural lighting conditions throughout this study. 3. The annual reproductive curves of all the experimental groups consisted of two separate laying periods. The first period was induced by the supplemental lighting programme while the second was induced by the naturally increasing photoperiod in this subtropical region. The first laying period of the experimental groups occurred in the breeding season, and the second was relocated to the non-breeding season. 4. The supplemental lighting could shift the laying periods of geese to the non-breeding season and had no significant effect on annual reproductive performance. The supplemental light programmes described here were able to manipulate the reproductive season of geese reared in open houses, which would be of practical value.     

植物类化学物质对家禽氧化应激和免疫反应的潜在功能

植物化学物质存在于各种植物和真菌中,是一种非营养性化合物,对动物具有多种有益的生物活性。近年来,随着抗生素的限制,植物化学物质已被认为是家禽生产过程中应对挑战的首选。快速生长型肉用鸡品种在生长环境中受到应激时表现出较强的脆弱性,降低家禽生产性能的氧化还原平衡可能与免疫系统有关,因为氧化应激和炎症损伤是一个多阶段过程。本文首先讨论了氧化应激和炎症对家禽业的影响,其次综述了近年来植物化合物的抗氧化和免疫调节作用的研究进展。     

Research Progress on Genetic Breeding and Reproduction of Domestic and International Rabbits in 2019

The rabbit is a kind of grain-saving and small herbivore animal.Rabbit breeding which is low investment and obvious efficiency has become an advantageous industry of increasing income of rural farmers and poverty alleviation.In recent years,with the development of life science,great progress has been made in rabbit genetic breeding at home and abroad.In this paper,the research progress in genetic breeding and reproduction of rabbits in 2019 are reviewed from the traditional breeding,molecular breeding and reproduction of rabbits.For abroad,lots of researches involved in traditional breeding,molecular breeding and reproduction were done.Effects of selection,environment and additives on productive performance had been analyzed in traditional breeding.Molecular breeding mainly focused on reproductive performance among which there were more studies on litter size and spermatine.Secondly,the related genes of growth,meat quality and hair color were studied.The research on reproduction mainly focuses on the preservation method of male rabbit semen and the effects of additives on rabbit semen quality,litter size and conception rate.In China,genetic breeding and reproduction research on rabbit also mainly included traditional breeding,molecular breeding and reproduction,but the focus of domestic research was molecular breeding,among which breed and genetic diversity and functional genes of fur trait were mainly researched using high-throughput sequencing,gene cloning and gene editing to screen the important functional genes and regulatory networks related to research traits.However,compared with molecular breeding,there are fewer studies on the traits evaluation of traditional breeding and rabbit reproduction.This review can provide references for rabbit breeding and production.     

2019年国内外家兔遗传育种与繁殖研究进展

家兔是节粮型草食小动物,其养殖投资少、见效快,已成为中国促进农民增收、助力脱贫攻坚的优势产业。近年来,随着生命科学的发展,国内外家兔遗传育种取得了较大进展。文章分别从家兔传统育种、分子育种和繁殖等方面对国内外2019年家兔遗传育种与繁殖研究进展进行了综述。国外在传统育种、分子育种和家兔繁殖方面均作了较多的研究,传统育种主要是针对选择和环境及添加物对家兔生产性能影响的研究;分子育种方面主要是对繁殖性状相关基因的研究,其中产仔数及精液蛋白方面的研究较多,其次是生长、肉质、毛色等性状相关基因的研究;而繁殖方面的研究主要针对公兔精液的保存方法及添加物对家兔精液品质、产仔数和受胎率的影响。国内家兔遗传育种与繁殖研究也主要包括传统育种、分子育种和家兔繁殖,但国内的研究重点在分子育种研究,其中品种与遗传多样性及皮毛性状功能基因的研究较多,主要采用高通量测序、常规基因克隆和基因编辑的方法筛选对研究性状具有重要调控功能的基因及调控网络;而传统育种性状评定和家兔繁殖方面的研究相对较少。该综述可为家兔的育种和生产研究提供参考。     

Sustainable transparent farm animal breeding and reproduction

Farm animal breeders are facing challenges. More and more powerful technologies are at their disposal for creating genetic change. At the same time, society is concerned about the impact of breeding practices and the use to which new technologies are being put. European breeders must compete in a global market. To meet these challenges, European farm animal breeders have conducted three projects to contribute to sustainable and transparent farm animal breeding and reproduction. In “Farm animal breeding and society”, an overview is presented of farm animal breeding in Europe and its technical, ethical, legal and consumer constraints and possibilities. In ‘SEFABAR’, European breeders, scientists and socio-economists have worked towards sustainable breeding and reproduction scenarios. In ‘CODE–EFABAR’, breeders aim to develop, with experts on ethics, communication and certification, and in close contact with NGOs, farmers' organisations and policy makers, a Code of Good Practice for farm animal breeding and reproduction organisations. Along this Code of Good Practice organisations will be able to explain their goals and practices to the public in a transparent way. This paper reviews these projects.     

舍内关键环境因子对畜禽健康影响的研究进展

养殖环境是影响畜禽健康和生长的重要因素,饲养密度过高易导致畜禽舍内局部空气温湿度、空气环境颗粒物和有害气体浓度升高,畜禽易出现热应激和呼吸道疾病,降低生长性能。明确养殖不利环境因素对畜禽健康的影响和机制,对于通过改善养殖环境提高畜禽健康状况具有重要意义。文章针对畜禽舍高温、颗粒物和有害气体等关键环境因子对畜禽生长性能、繁殖性能、免疫性能和呼吸道健康等的影响进行综述,针对存在问题提出建议,旨在为我国畜禽养殖产业转型升级与可持续发展提供理论依据。     

激素对家禽卵泡发育的调节

从家禽的生殖生理特点出发，根据近年来有关研究资料，系统地综述了促进性腺激素释放激素，促性腺激素，孕激素，肾上腺皮质激素、性腺激素、细胞因子、褪黑素和前列腺素对家禽卵泡发育和排卵的调节机理，对于促进家禽卵泡发育，提高家禽繁殖性能提供了科学的参考。     

肉鸡福利评价指标研究进展

随着高密度、集约化畜牧业的发展,动物福利问题不容乐观,严重制约了我国畜牧业的发展。这种以牺牲动物福利为代价的生产,对家禽的生长造成了不良的生理和心理反应,导致呼吸道疾病、腹水症等的爆发,降低了生产性能、经济效益和产品质量。近年来,各国对动物福利问题日益重视。本文通过总结和分析肉鸡福利评价的指标,旨在为我国家禽福利评价体系的建立提供理论依据,提高肉鸡养殖福利水平,推动畜牧业的健康发展。     

畜禽场氨减排技术研究进展

近年来,随着规模化养殖业的迅速发展,畜禽饲养密度不断增大,导致养殖业氨排放量大幅上升,严重影响畜禽健康及其生产性能,同时造成大气污染,因此开展养殖场氨减排技术研究对于畜禽健康、产品安全和环境改善均具有重要意义。着眼于畜禽内源氨营养调控、畜禽舍内原位净化和粪污处理过程三个重点环节,综述了多种氨减排技术,包括从源头的饲料优化、粪便除臭剂使用、舍内空气净化及粪污处理过程中的固液分离、表面覆盖等技术,对于养殖业氨减排具有一定参考意义。     

The broiler breeder paradox: ethical, genetic and physiological perspectives, and suggestions for solutions

1. Due to intensive selection, broiler chickens became the most efficient meat-producing animals because of their fast growth, supported by a virtually unlimited voluntary feed intake. These characteristics cause many problems in the management of broiler breeder hens because of the negative correlation between muscle growth and reproduction effectiveness. 2. This problem, namely the fast muscle growth versus reproduction health paradox, induces a second paradox, acceptable reproduction and health versus hunger stress and impaired welfare, because broiler breeder hens require dedicated programmes of feed restriction (1) to maximise egg and chick production and (2) to avoid metabolic disorders and mortality in broiler breeders. 3. Given that poultry selection is a global large-scale business and chickens are a prolific species, improvement in profit can only be obtained by selecting on feed conversion and/or for higher breast meat percentage, which will intensify the broiler-breeder paradox. 4. New feeding strategies are being studied, but it is questionable if the paradox can be solved by management tools alone. Because breeding and selection are long-term processes, involving animals, farmers, consumers, industry, environment etc., a more sustainable breeding goal needs to be determined by a multidisciplinary approach and an open debate between several actors in the discussion. 5. Using dwarf broiler breeder hens could be one alternative, because dwarf hens combine relatively good reproductive fitness with ad libitum feeding. Another possibility is to accept lower broiler productivity by assigning economic values to welfare and including integrity traits in an extended breeding goal.     

Reproductive performance of dwarf broiler breeders given different allowances of food during the rearing and breeding periods and two lighting patterns

1. Dwarf broiler breeders were either fed ad libitum or restricted to allow growth to mean body weights of 1.4 or 1.8 kg at 20 weeks of age. During the breeding period these birds were fed ad libitum, or food was restricted to different degrees and the birds subjected to two different incremental lighting patterns. 2. Egg production of birds fed ad libitum during the breeding period increased with the degree of food restriction during rearing. 3. Food restriction during the breeding period increased the egg production of birds weighing 1.8 kg at 20 weeks but decreased that of birds weighing only 1.4 kg. 4. Fertility was relatively low and inversely related to body fatness of females. 5. The differences in lighting pattern did not influence performance. 6. For optimum reproductive performance during the rearing period dwarfs should not be restricted so severely as conventional breeders. Best chick production was obtained from birds with a bodyweight of 1.8 kg at 20 weeks of age, which were subjected to a 10% restriction of food during the breeding period.     

影响犬繁殖的因素

许多因素包括母犬的品种,年龄,健康,繁殖历史,交配类型,环境,以及母犬的营养水平,都影响了繁殖和幼犬的健康和性质的最终结果。这些不同的影响似乎独立的出现,但是之间有共同的关联。在育种计划中,繁育者在某种程度上要对所有这些加以控制。本文综述了影响犬繁殖的因素,这对于饲养和育种管理的有效的咨询辅导是至关重要的。     

Similar improvements in reproductive performance of male line, female line and parent stock broiler breeders genetically selected in the UK or in South America

1. Field data on the reproductive performance of parent stock and grandparent female line and male line broiler breeders were extracted from a commercial database covering the years of hatch from 1989 to 2002. The data were from the UK, Western Europe, Central and South America and Japan. Quadratic regression curves were fitted to the data to estimate the long-term phenotypic trends in total egg production, hatching egg production, chick numbers, hatchability and female mortality. 2. Changes in performance over time were similar in the UK, Western Europe and Central and South America and are consistent with the suggestion that genetic selection in separate breeding programmes in the UK (supplying the UK and Western Europe) and Brazil (serving Central and South America) was associated with similar improvements in the performance of commercial parent stock and grandparent flocks. Changes in performance in Japan (supplied from the UK) were different but recent performance was similar to those in the other regions. 3. The mean annual improvements over 10 years to 2002 for male line, female line and parent stock, respectively, were 0.4, 1.7 and 1.7 for total egg number; 0.5, 1.8 and 1.6 for hatching egg number; 0.6, 1.8 and 1.3 for total chick production; 0.25, 0.47 and 0.09% for hatchability; and -0.69, -0.05 and -0.41% for female mortality. 4. The results are consistent with claims that significant genetic change in pedigree selection (nucleus) flocks by the primary breeding company are reflected in substantial improvements in reproductive performance in commercial flocks. The presence of similar rates of improvement in different geographical regions as a result of genetic selection in two continents representing tropical and temperate regions suggests that genotype-environment interactions for reproduction traits are not important.     

Relationship between reproductive and productive performance in poultry flocks

The author analyses the interrelationship between the hygienic prerequisites of reproduction and performance in poultry farming, with regard to their impact on human health. The main factors influencing the hatching rate of poultry eggs are reviewed along with their epizootiological and economic aspects, and the possibilities of the prevention of egg-transmitted diseases are discussed.     

The Main Research Fields and Progress of Livestock Epigenetics

Epigenetics means that there are heritable changes in gene expression while without a change in DNA sequence.In the recent years,the researches of epigenetic regulation on livestock field have developed rapidly.The main studied domestic animals include poultry,swine,bovine,sheep and goat,thus a new subject——livestock epigenetics is developing.Livestock epigenetics mainly uses various kinds of epigenetic modifications involved in DNA methylation,histone modification and non-coding RNAs regulation to study livestock growth and development,disease resistance,reproduction and economic traits,and so on.Here,we reviewed the mainly research fields and progress on livestock epigenetics,the trends of livestock epigenetics studies were also discussed to comprehensively understand the molecular basis of the complex traits formation of livestock and poultry,which greatly broadened the research and strategy to improve the economic traits of livestock and poultry.     

畜禽表观遗传学主要研究领域及研究进展

表观遗传学（epigenetics）是指DNA序列未发生变化,而基因表达却发生了可遗传的变化。近年来,表观遗传学在家养动物研究领域发展极为迅速,主要畜种涉及鸡、猪、牛、羊等,并形成一门新兴学科--畜禽表观遗传学（livestock epigenetics）。畜禽表观遗传学主要针对各种表观遗传修饰,包括DNA甲基化、组蛋白修饰及非编码RNA等,研究家养动物的生长发育、疾病抗性、繁殖、经济等性状的表达调控基础。作者综述和分析了畜禽表观遗传学的主要研究领域及现状,进一步对其发展趋势进行了展望,有助于全面了解畜禽复杂性状形成的分子基础,这也极大开拓了研究和改善畜禽各类经济性状的思路与策略。