蝇蛆的营养特性及其在畜禽生产中的应用研究进展

蝇蛆繁殖能力强、生长周期短、养殖成本低,其粗蛋白质、不饱和脂肪酸和矿物质等含量高,必需氨基酸种类较齐全,并可提取几丁质、凝集素和抗菌肽等生物活性物质,是一种优质的昆虫蛋白质饲料。研究表明,蝇蛆及其制品能够部分替代饲粮中常规蛋白质饲料,提高畜禽生长或生产性能、提升产品品质、增强机体抗氧化和免疫功能以及调节肠道菌群结构。本文综述了蝇蛆的营养特性及其应用于畜禽生产中的最新研究成果,以期为其在养殖业中的应用及进一步研究提供参考。     

Essential oil and aromatic plants as feed additives in non-ruminant nutrition:a review

This paper summarizes the current knowledge regarding the possible modes of action and nutritional factors involved in the use of essential oils(EOs) for swine and poultry.EOs have recently attracted increased interest as feed additives to be fed to swine and poultry,possibly replacing the use of antibiotic growth promoters which have been prohibited in the European Union since 2006.In general,EOs enhance the production of digestive secretions and nutrient absorption,reduce pathogenic stress in the gut,exert antioxidant properties and reinforce the animal's immune status,which help to explain the enhanced performance observed in swine and poultry.However,the mechanisms involved in causing this growth promotion are far from being elucidated,since data on the complex gut ecosystem,gut function,in vivo oxidative status and immune system are still lacking.In addition,limited information is available regarding the interaction between EOs and feed ingredients or other feed additives(especially pro- or prebiotics and organic acids).This knowledge may help feed formulators to better utilize EOs when they formulate diets for poultry and swine.     

Research Progress of the Influence of Threonine on Poultry Nutrition

Threonine (Thr) is one of the four main limiting amino acids of poultry, and it plays a very important role in poultry's maintenance of normal growth, development and immune function. Although there have been very comprehensive studies on the mechanism of broilers and laying hens over the past ten years, there are still relatively fewer studies on ducks. This paper summarizes recent studies on Thr nutrition-physiological function in broilers, laying hens and ducks, including the influence of Thr on dietary amino acids balance, production performance, carcass quality, immune function and intestine health maintenance. At the same time, this paper also briefly analyzes the factors related to Thr requirement, including growth stage, crude protein level, energy concentration, other amino acids level in diet and raising environment. In brief, the review is respected to guide poultry production practices.     

Essential oil and aromatic plants as feed additives in non-ruminant nutrition: a review

This paper summarizes the current knowledge regarding the possible modes of action and nutritional factors involved in the use of essential oils (EOs) for swine and poultry. EOs have recently attracted increased interest as feed additives to be fed to swine and poultry, possibly replacing the use of antibiotic growth promoters which have been prohibited in the European Union since 2006. In general, EOs enhance the production of digestive secretions and nutrient absorption, reduce pathogenic stress in the gut, exert antioxidant properties and reinforce the animal’s immune status, which help to explain the enhanced performance observed in swine and poultry. However, the mechanisms involved in causing this growth promotion are far from being elucidated, since data on the complex gut ecosystem, gut function, in vivo oxidative status and immune system are still lacking. In addition, limited information is available regarding the interaction between EOs and feed ingredients or other feed additives (especially pro- or prebiotics and organic acids). This knowledge may help feed formulators to better utilize EOs when they formulate diets for poultry and swine.     

苏氨酸在家禽营养中的研究进展

苏氨酸是家禽体内4种主要的必需氨基酸之一,对维持家禽正常的生长、发育及免疫具有十分重要的作用。尽管过去十多年来有关苏氨酸对肉鸡、蛋鸡的影响机理研究较为全面,但在肉鸭上的研究相对较少。作者总结了近年来苏氨酸在肉鸡、蛋鸡和肉鸭生物学和营养生理功能上的研究成果,主要包括苏氨酸在平衡日粮氨基酸、促进蛋白质合成、提高生产性能、提升胴体品质、增强免疫机能及维护肠道健康等方面的作用效果;同时也简要分析了家禽苏氨酸需要量的影响因素,包括家禽的生长阶段、日粮粗蛋白质水平、日粮能量浓度、日粮其他氨基酸含量及饲养环境等,以期为家禽的生产实践提供一定的指导。     

黄粉虫的营养特性及其在畜禽饲粮中的应用效果

蛋白质是动物饲粮的第二大成分,然而中国饲料蛋白质原料资源日益短缺,严重制约了畜牧业的健康可持续发展。黄粉虫（Tenebrio molitor L.）食性广、繁殖快、产出高,属于可再生的生物资源,其干物质中粗蛋白质、甲壳素、不饱和脂肪酸、维生素等含量较丰富,能够提取具有抗菌、抑炎、免疫调节等功能的生物活性物质,如抗菌肽、凝集素,且具有生长快、易规模饲养、占用土地少等优点,有望成为一种新型蛋白质饲料资源,进而缓解当前饲料蛋白质原料不足的现状。有研究表明,黄粉虫可以部分替代饲粮中的常规蛋白质饲料原料,提高畜禽生长或生产性能,改善产品品质,以及提高畜禽机体健康水平。作者阐述了黄粉虫的营养成分、畜禽对黄粉虫营养物质的消化率,在参考国内外最新研究成果的基础上综述了黄粉虫部分替代常规蛋白质饲料原料,改善畜禽生长或生产性能,提高肉禽屠宰性能,改善家禽产品品质,调节畜禽机体物质代谢,增强机体免疫和抗氧化功能以及改善肠道健康的作用,并对其在畜禽生产中的应用前景进行展望,以期为推广黄粉虫在畜牧业中的应用提供参考。     

日粮氨基酸对犊牛生长和健康影响的研究进展

犊牛在断奶前免疫系统发育不成熟，体质敏感，而在断奶后生长发育迅速。这两个阶段的犊牛都需要提供含有优质蛋白质的日粮以保证其生长发育。结合中国蛋白质资源紧缺的现状，做好犊牛阶段的氨基酸营养在促进犊牛健康生长和提高蛋白质利用率上都具有重要作用。此外，氨基酸在提高犊牛免疫力方面有不可替代的作用，近年来的研究还发现，氨基酸对犊牛消化道易感细菌和病毒有特殊的抑制功能。针对犊牛生长速度快、免疫功能不完善、死亡率高、断奶前后生理结构和营养需要变化迅速的生理特点，作者重点介绍了单一氨基酸不同水平及多种氨基酸不同比例对犊牛断奶前后生长性能的影响，并从氨基酸提高犊牛自身免疫力和抑制微生物繁殖两方面来阐述氨基酸对犊牛健康的影响机制，以期为推进氨基酸在犊牛生产中的应用提供理论依据。     

分泌性免疫球蛋白A与肠道黏膜免疫的关系及其分泌的营养调控

分泌性免疫球蛋白A(SIgA)是由J链连接成的二聚体免疫球蛋白A(IgA)与分泌片段结合后形成的复合物。肠道内的SIgA是肠道黏膜免疫中的重要环节之一。SIgA可维持肠道黏膜内环境稳态,调控肠道内源微生态,并在黏膜上皮通过干扰病原体与上皮细胞受体结合,阻止病原体附着宿主细胞,影响病原菌毒力及免疫排异,从而阻止病原体的传播和进一步的感染,因而在免疫防御中起着非常重要的作用。营养因子(如脂肪酸、氨基酸、维生素等)在机体受到病原菌入侵或应激的情况下,可显著促进肠道SIgA的分泌,提高机体对病原菌的抵抗能力,在一定程度上改善应激动物的生产性能。     

Strategies to modulate the intestinal microbiota and their effects on nutrient utilization,performance, and health of poultry

Poultry is widely produced and consumed meat global y. Its demand is expected to continue increasing to meet the animal protein requirement for ever-increasing human population. Thus, the chal enge that poultry scientists and industry face are to produce sufficient amount of poultry meat in the most efficient way. In the past, using antibiotics to promote the growth of poultry and manage gut microbiota was a norm. However, due to concerns over potential fatalistic impacts on food animals and indirectly to humans, their use as feed additives are banned or regulated in several jurisdictions. In this changed context, several alternative strategies have been proposed with some success that mimics the functions of antibiotics as growth promoters and modulate gut microbiota for their beneficial roles. These include the use of probiotics, prebiotics, organic acids, and exogenous enzyme, among others. Gut microbiota and their metabolic products improve nutrient digestion, absorption, metabolism, and overal health and growth performance of poultry. This paper reviews the available information on the effect of feed additives used to modulate intestinal microbiota of poultry and their effects on overal health and growth performance. Understanding these functions and interactions wil help to develop new dietary and managerial strategies that wil ultimately lead to enhanced feed utilization and improved growth performance of poultry. This review wil help future researchers and industry to identify alternative feed ingredients having properties like prebiotics, probiotics, organic acids, and exogenous enzymes.     

热应激畜禽的营养调控

夏季高温环境下,畜禽极易发生热应激。畜禽发生热应激后其生产性能降低,严重影响养殖效益。营养调控措施是根据畜禽的发育规律,通过调配适宜的营养成分和含量,降低热应激对畜禽的生长过程的影响,使畜禽养殖朝着健康、绿色、持续、高效的方向发展。从调节电解质、矿物质、维生素等营养调控的角度综述了热应激防控的最新研究进展,以期为防控热应激和寻找新的措施、最大限度地降低畜牧业生产损失提供有益的思路。     

Tryptophan in poultry nutrition: Impacts and mechanisms of action

Many studies have shown that productivity, immune system, antioxidant status, and meat and egg quality can be optimized by dietary supplementation with amino acids that are not usually added to poultry diets. Understanding the effects of these amino acids may encourage feed manufacturers and poultry producers to include them as additives. One of these amino acids is tryptophan (Trp). The importance of Trp is directly related to its role in protein anabolism and indirectly related to its metabolites such as serotonin and melatonin. Thus, Trp could affect the secretion of hormones, development of immune organs, meat and egg production, and meat and egg quality in poultry raised under controlled or stressed conditions. Therefore, this review discusses the main roles of Trp in poultry production and its mode (s) of action in order to help poultry producers decide whether they need to add Trp to poultry diets. Further areas of research are also identified to address information gaps.     

反刍家畜营养免疫学研究进展

本文对氨基酸，脂肪酸，低聚糖，维生素，矿物质等各类营养素在反刍家畜免疫中的作用及其补饲效果进行了综述。     

小肽对家禽肠道生理功能的影响

家禽肠道生理功能与家禽机体健康状态关系密切,维护家禽肠道生理功能是实现家禽健康养殖的关键。小肽以其独特的营养特性和吸收机制能够促进家禽肠道系统发育、肠道消化酶的分泌、肠道有益菌的大量繁殖、微量元素的吸收及肠道免疫力的提高,从而增强肠道的屏障作用和养分吸收能力,对肠道起到保护作用。开发以小肽为主的新型饲料添加剂在维护家禽肠道生理功能,实现健康养殖方面潜力巨大。     

木薯及其副产品的营养价值及在动物生产中的应用

木薯耐干旱、耐贫瘠且易管理，其茎叶、块根及工业副产物营养物质含量较高，是一种优质的非常规饲料。木薯叶粗蛋白质、粗脂肪、灰分含量较高，含有丰富的钙、铁、锌、锰。木薯块根是很好的能量来源，其粗蛋白质、粗脂肪、矿物质、维生素含量低于木薯叶。木薯渣主要由木薯的外皮、破碎细胞壁等组成，粗蛋白质含量很低，粗纤维、中性洗涤纤维、酸性洗涤纤维含量较高，矿物质、氨基酸丰富，但钙、磷、氨基酸不平衡。木薯品种、生长条件、收割方式、收获时间、加工工艺等均会影响木薯及其副产品营养物质的含量。木薯中含有氰化物、单宁及植酸等抗营养因子，其中氰化物是限制木薯应用的最主要因素，其可结合细胞色素C氧化酶，阻断线粒体电子传递链，抑制有氧呼吸，导致中枢神经系统抑制和死亡。单宁、植酸与蛋白质结合生成络合物，阻碍营养物质的消化吸收，可通过水煮、烘烤、干燥等物理化学方法，以及发酵、育种等手段对木薯进行脱毒。研究表明，木薯及其副产品可广泛应用于动物生产中，对动物生长性能、肉品质无不良影响。开发与利用非常规饲料有利于缓解饲料资源紧张，降低养殖成本。作者详细介绍了木薯及其副产品的营养价值、抗营养因子及其脱毒方法以及其在动物生产上的应用，以期为木薯在畜禽养殖中的综合利用提供一定的参考。     

丝氨酸的生理功能及其在猪生产中的应用研究进展

丝氨酸可通过内源性途径合成,在传统营养学上属于非必需氨基酸。在机体正常生理功能下,丝氨酸广泛参与嘌呤合成、一碳代谢、谷胱甘肽合成以及脂质合成等多个重要的机体代谢过程。此外,丝氨酸还对细胞增殖分化、氧化还原平衡、神经系统和免疫功能等具有调节作用。近期研究发现,丝氨酸有益于肠道健康,且可提高猪的生长性能。本文主要综述了丝氨酸的生理功能及其在养猪生产中的应用,为丝氨酸的研究及在畜牧生产中的应用提供参考。     

北京鸭苏氨酸营养研究进展

苏氨酸是家禽第三限制性氨基酸,对北京鸭生长发育、肠道健康、免疫机能、脂肪代谢等方面都有重要的调节作用。北京鸭是中国自主培育的肉鸭品种,具有生长发育快、育肥性能好等特点,是闻名中外的"北京烤鸭"的制作原料。作者总结了近几年国内外苏氨酸调节北京鸭营养及生理功能的研究成果,包括苏氨酸对不同日龄、不同品系北京鸭生长性能的影响,以及苏氨酸对北京鸭屠宰性能、免疫功能、肠道健康以及脂肪代谢的影响及其代谢机制等方面,汇总了近几年关于苏氨酸需要量的研究成果,利用二次曲线断线模型和直线-断线模型,以日增重、平均日采食量、胸肌率、料重比等为指标重新评估了1~14/21日龄北京鸭的苏氨酸需要量,推荐满足1~21日龄北京鸭最大日增重和产肉的苏氨酸需要量为0.60%~0.67%。然而生长后期北京鸭的苏氨酸需要量研究较少,还需要进一步研究。此外,还需要进一步研究苏氨酸调节北京鸭脂肪代谢、肠道健康和免疫功能的分子机制。     

驴乳营养成分研究进展

驴乳因其乳清蛋白、乳糖、溶菌酶、不饱和脂肪酸和VC含量较高而酪蛋白及脂肪含量较低的特点，被誉为人乳的理想替代品，同时具有低致敏性、抑菌性和抗癌活性等多种生理功能。本文介绍驴乳的营养成分特点，包括蛋白质、氨基酸、脂肪、矿物质、维生素等，并与人乳、牛乳、水牛乳、羊乳和骆驼乳进行比较，以期为驴乳的综合加工与利用提供参考。     

Nutrition--mechanisms of immunosuppression.

Nutritionists must formulate diets that supply adequate amounts of nutrients from five major groups. These are carbohydrate, protein (amino acids), fat, minerals and vitamins. Carbohydrate is usually a cheaper source of energy than fat, but fat is often used to increase the caloric concentration of the diet. Variations in energy intake which may effect immunocompetence usually result from management practices rather than diet formulation. Feed restriction for broiler breeders and withholding feed in forced molting practices may affect immunocompetence. Feed restriction causes higher plasma corticosterone levels, which are known to decrease the immune response, possibly through effects on cytokines. Excessive feed, through forced feeding, may also have short-term effects on indicators of humoral immunity. Protein and amino acid nutrition have been studied in relation to immunocompetence. The level of dietary amino acid needed to maximize growth and feed efficiency will also generally maximize measures of immunocompetence. The level of amino acids needed for maximum growth is lower in chicks which have been immunologically stressed than in chicks which have not. An immune response changes metabolism so that less growth occurs, thereby decreasing the need for amino acids. Dietary levels of minerals can affect immunocompetence. While deficient levels of sodium and chloride decrease humoral immunity, levels of these nutrients which supported maximum growth also supported maximal humoral immunity. Low dietary zinc levels did not affect indicators of immunocompetence in the chick. The effect of fat soluble vitamin levels on the immune system has been studied. Vitamin A is needed to maintain epithelial tissue and prevent infection. Cellular immune response is decreased when the chick is deficient in this nutrient. Several indicators of immune responsiveness are depressed when chicks are vitamin E and/or selenium deficient. Since these nutrients serve as antioxidants, cellular integrity may be affected by a deficiency. Cellular integrity is very important for receiving, and responding to the messages needed to coordinate an immune response. High levels of vitamin E (greater than 10 times the required level) have been found to be immunostimulatory.     

牛磺酸在动物内分泌系统中的生理作用

牛磺酸是一种含硫条件性必需氨基酸,对机体生长发育、繁殖、免疫机能等有重要的营养和生理作用。研究表明,机体缺乏牛磺酸时,内分泌系统功能发生障碍,导致各种内分泌疾病发病率上升,包括甲状腺功能亢进、生殖功能退化、糖尿病、肾脏疾病等内分泌疾病,阻碍机体正常的生长与发育,严重影响畜牧养殖业。近年来,关于牛磺酸对内分泌系统作用的研究并不多,临床上的应用上更不多见。论文对牛磺酸在下丘脑-垂体、甲状腺、肾上腺、性腺、胰岛等器官的内分泌作用进行综述,为牛磺酸在畜牧生产中的应用提供参考。     

Fish meal--nutritive value

Understanding the interactions between nutrition and immune system is crucial for adjusting nutrient allowances in dietary formulations that optimize production efficiency. Among various animal proteins, fish meal (FM) is rich in protein (amino acids), readily available throughout most of the world, and competitively priced against other animal proteins (e.g. milk and blood). In addition, many researchers reported that FM is traditionally recognized as a high digestible protein with a high content of amino acids, vitamins and minerals for pigs. Supplementation of fatty acids by FM and fish oil (FO) is one strategy to modify an animal immune response. As a result of FM and FO effects, those supplementations can result in improved performance and immunity of young animals.