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支链氨基酸(branched-chain amino acids, BCAA)在家禽生长、生产性能、免疫功能和肠道健康等方面发挥着重要作用,涉及器官发育、免疫反应、肌肉蛋白周转和基因调控等关键过程。然而,单一BCAA的过量、缺乏或比例失衡均会影响家禽蛋白质合成和肠道健康,因此保持BCAA比例的平衡对于家禽的生产性能至关重要。尽管NRC(1994)提供了肉鸡、蛋鸡和种鸡的BCAA推荐量,但不同日粮蛋白质水平以及不同品种和生长阶段的家禽对BCAA的需求存在差异。同时,鉴于抗生素生长促进剂的禁用及养殖端所面临的多种疾病的挑战,也需要重新评估家禽对BCAA的推荐摄取水平。另外,BCAA在维持肠道完整性、调控肠道微生物组成以及提高机体蛋白周转效率的作用机理研究仍有待进一步探究。本综述在阐述BCAA在家禽中的营养生理作用以及其对生产和健康的基础上,推荐了不同饲养条件下不同肉鸡品种(肉鸡、蛋鸡和种鸡)BCAA需要量,以期为家禽低蛋白日粮BCAA推荐量提供理论参考。 相似文献
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苏氨酸在肉鸡、蛋鸡饲料中的应用研究进展 总被引：2，自引：0，他引：2
苏氨酸(Thr)的化学名称为α－氨基－β羟丁酸，分子式为NH2－CH(COOH)－CHOH－CH3。它有4种异构体，其中D－苏氨酸难以被动物吸收和利用(Baker.D.H等，1998)，天然存在的是L－苏氨酸，通常添加的苏氨酸一般都指L－苏氨酸，是动物生长所必需的氨基酸。苏氨酸已被证明是鸡饲料中继蛋氨酸、赖氨酸之后的第三个限制性氨基酸。由于苏氨酸的这种重要性，已成为影响肉鸡、蛋鸡生产性能的一个限制性因素，在日粮中添加适量苏氨酸已越来越为人们所重视。1肉鸡、蛋鸡苏氨酸缺乏症以及日粮中添加苏氨酸的效果 鸡日粮缺乏苏氨酸时整体表现采… 相似文献
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Uz曾报道在含粗蛋白16.5％的肉鸡生长后期日粮中添加L-盐酸赖氨酸和DL-蛋氨酸明显地改进了饲料转化率,而添加L-苏氨酸和L-色氨酸则没有作用。他指出,赖氨酸和蛋氨酸分别是第一,第二限制氨基酸。比较低蛋白日粮和NRC标准的氨基酸组成,肉鸡生长后期日粮第三限制氨基酸可能是苏氨酸或者是色氨酸。本实验目的在于研究添加L-盐酸赖氨酸和DL-蛋氨酸的肉鸡生长后期低蛋白日粮中补充L-苏氨酸和DL-色氨酸的效果。 相似文献
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苏氨酸在肉鸡蛋鸡饲料中的应用研究 总被引：1，自引：0，他引：1
苏氨酸的化学名称为α－氨基－β羟丁酸，分子式为NH－CH（COOH）－CHOH－CH，分子量为119，它有四种异构体，其中D－苏氨酸难以被动物吸收和利用（Baker．D．H等，1998），天然存在的是L－苏氨酸，我们所添加的苏氨酸一般都指L－苏氨酸，它是动物维持和生长所必需的氨基酸。由于这种重要性，苏氨酸逐渐成为影响肉鸡、蛋鸡生产性能的一个限制性因素，在日粮中添加适量苏氨酸已越来越为人们所重视。1 肉鸡、蛋鸡苏氨酸缺乏症以及日粮中添加苏氨酸的效果鸡日粮缺乏苏氨酸时整体表现是采食量下降（Wtanabe．R等，1997），关于苏氨酸… 相似文献
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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。 相似文献
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日粮添加维生素A对肉鸡和蛋鸡生长性能及免疫功能的影响 总被引：1，自引：0，他引：1
试验研究了不同的维生素A(VA)添加水平对肉鸡和蛋鸡的生长性能及机体免疫功能的影响.试验选用1日龄的雌性蛋鸡和雌性肉鸡各270只,分别随机分成3个处理,每个处理6个重复,每个重复15只,分别饲喂含维生素A 0(对照)、4 000和20 000 IU/kg的日粮,饲养试验时间为84 d.试验结果表明,日粮添加维生素A为0 IU/kg处理的肉鸡和蛋鸡的采食最显著高于添加维生素A的各处理(P＜0.05);日粮维生素A添加水平对肉鸡和蛋鸡的免疫器官指数(胸腺指数、脾脏指数和法氏囊指数)无显著影响(P＞0.05);对照的肉鸡和蛋鸡异嗜粒细胞/淋巴细胞(H/L)高于其他处理(P＞0.05);肉鸡和蛋鸡绵羊红细胞(SRBC)抗体滴度和新城疫(ND)抗体滴度随着日粮维生素A添加水平的升高而升高;日粮添加4 000 IU/kg维生素A处理的肉鸡和蛋鸡钥孔戚血蓝蛋白(KLH)抗体滴度、白蛋白浓度和白介素-2(IL-2)的浓度最高.蛋鸡的免疫器官指数和血清白蛋白浓度显著高于肉鸡(P＜0.05);肉鸡和蛋鸡的其他免疫指标差异不显著(P＞0.05).综上所述,日粮添加4 000 IU/kg维生素A能提高肉鸡和蛋鸡的生长性能和免疫功能,当添加水平达到20 000 IU/kg时,可对生长性能和免疫机能产生不利影响.肉鸡和蛋鸡的主要免疫指标没有最著差异. 相似文献
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苏氨酸的营养免疫作用及畜禽对其需要量的研究 总被引：1，自引：0，他引：1
苏氨酸作为畜禽的第二或第三限制性氨基酸,对机体有重要的营养免疫作用,在日粮氨基酸的平衡中也起重要作用。不同生长阶段的畜禽对苏氨酸的需要量不同。此外,其它一些氨基酸如赖氨酸、蛋氨酸、色氨酸、甘氨酸等均对苏氨酸的需要量有影响。 相似文献
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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. 相似文献
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海藻用作畜禽饲料的进一步研究 总被引：2，自引：0，他引：2
本项研究在调查我国海藻资源量,分析其化学成分的基础上,用40头生长肥育猪、800只产蛋鸡、3000只蛋鸭及3900只肉鸭做了共5次饲养试验以及生产应用观察。结果表明:海藻粉以适当比例加到饲粮中能改善饲粮适口性,增进采食量,并明显提高畜禽生产性能及繁殖能力。加入2％的海藻粉可使生长猪增重速度提高12％,使蛋黄含碘量增加10倍。海藻粉在畜禽饲粮中的用量以2—5％为宜。 相似文献
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《The Journal of Applied Poultry Research》2015,24(2):267-282
Poultry nutritionists should constantly evaluate their feeds and feeding programs in view of the changes that continue to be made to the potential growth rate of broilers and egg production in laying hens with the objective of providing the birds with the optimum economic level of nutrients at all times. In this review, the models generated at Universidade Estadual Paulista (UNESP) Jaboticabal, to estimate the optimum intake of amino acids (AA) for broilers and laying hens are presented. These models were used to estimate the variation in AA intake within a broiler population making use of coefficients of variation that represent the real situation in a commercial broiler operation. The range of AA intakes obtained was compared to some commonly applied feeding programs and recommendations. Based on results of our developed models and other feeding programs, feeds were formulated and growth was predicted using a growth simulation model (Avinesp). The prediction of growth showed that these models are reliable and useful tools to assist the nutritionists in decision making. In a study with laying hens, the Reading model (RM) was used to establish optimum economic AA intakes in a flock of hens. The input variables were the means and standard deviations of egg output and BW, and the relationship between the marginal cost of the AA and the marginal revenue for eggs. Based on this model, the optimum intake of each AA can vary with each of the variables considered. The models proposed in our study enable important decisions to be made regarding AA intakes to be used to obtain optimum economic performance from a population of broilers and laying hens. 相似文献
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Effect of dietary threonine on laying performance and intestinal immunity of laying hens fed low‐crude‐protein diets during the peak production period 
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下载免费PDF全文 M. M. M. Azzam X. Y. Dong X. T. Zou 《Journal of animal physiology and animal nutrition》2017,101(5):e55-e66
Threonine (Thr) may be a limiting amino acid for laying hens fed diets with lowered protein level. An experiment was conducted to examine laying performance, and the intestinal immune function of laying hens provided diets varying in digestible Thr levels. Lohmann Brown laying hens (n = 480), 28 weeks of age, were allocated to six dietary treatments, each of which included five replicates of 16 hens. Dietary crude protein (CP) 16.18% diet was offered as the positive control diet. L‐Thr was added to the negative diet (14.16% CP) by 0, 1.0, 2.0, 3.0 and 4.0 g/kg, corresponding 0.44%, 0.43%, 0.49%, 0.57%, 0.66% and 0.74% digestible Thr. At 40 weeks, a reduction in CP level decreased laying performance (p < 0.05). In the low CP, increasing dietary Thr increased (p < 0.05) egg production and egg mass and rose to a plateau between 0.57% and 0.66%. The hens fed 0.66% Thr showed the lowest value (p < 0.05) of feed conversion ratio (FCR). Serum level of uric acid showed the lowest values (p < 0.05) at 0.57–0.66%. In addition, serum‐free Thr maximized (p < 0.05) between 0.66% and 0.74%. Digestive trypsin activity decreased (p < 0.05) when hens fed the low‐CP diet compared with hens fed CP (16.18%) and hens fed 0.57–0.66%. Expressions of ileal MUC2 mRNA maximized (p < 0.05) at 0.66% Thr. Occludin mRNA increased with increasing Thr level (p < 0.05). sIgA mRNA reached to the maximum level (p < 0.05) at 0.66% and 0.74% Thr. INF‐γ mRNA reached to the lowest level (p < 0.05) at 0.65%. Expressions of ileal IL‐2, IL‐6, IL‐1β mRNA decreased with increasing Thr level (p < 0.05). In conclusion, Thr supplementation resulting in optimal laying performance and stimulated the mucosal immune system, suggesting that it is a limiting amino acid in the low‐crude‐protein diet of laying hens during the peak production period. 相似文献
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本试验旨在通过4个剂量-反应试验,研究30～38周龄产蛋鸡对赖氨酸(Lys)、蛋氨酸(Met)、色氨酸(Trp)和苏氨酸(Thr)4种必需氨基酸(AA)的需要量及其比例.每个试验均采用360只海兰灰产蛋鸡,设5个处理,分别采食5个AA梯度水平的试验饲粮,每个处理6个重复,每个重复12只鸡.采用蛋公鸡回肠食糜法测定饲料原料的标准回肠可消化(SID)值.试验预试期14 d,正试期56 d.结果表明:海兰灰产蛋鸡的产蛋率、蛋重、日产蛋量和料蛋比与SIDLys、SID Met、SID Trp和SID Thr的摄入水平均有较好的折线回归关系;以日产蛋量为自变量(x),AA摄入水平为依变量(Y)分别建立的回归方程为:YSID Lys=51.60-0.041 6(682.5-x),R2=0.96;YsID Met=51.43-0.085(314.1-x),R2 =0.95;YSID Trp =51.17-0.155 4(163.0-x),R2=0.97;YsID Thr=52.85-0.057 6(499.5-x),R2=0.93.在饲粮粗蛋白质12.8％的条件下,以日产蛋量为参照指标确定的30 ～ 38周龄产蛋鸡的SID Lys、SID Met、SID Trp和SID Thr需要量分别为684、313、171和506 mg/(只·d).以日产蛋量为指标建立的30～38周龄产蛋鸡理想SID AA模式为:Lys:Met:Trp:Thr=100∶46∶24∶73. 相似文献
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为了研究虫草粉（古尼虫草地顶孢霉培养物）联合酵母硒对蛋鸡产蛋性能、蛋品质、抗氧化功能和免疫功能的影响,试验选用450羽24周龄海兰褐壳蛋鸡,随机分为5组,每组6个重复,每个重复15羽。对照组饲喂基础饲粮,试验Ⅰ~Ⅳ组饲喂添加0.1 mg/kg酵母硒联合不同剂量虫草粉（0、0.2%、0.3%和0.4%）的基础饲粮,试验期27周;选取产蛋高峰中期（第40周龄）蛋鸡进行产蛋性能、鸡蛋品质、免疫功能和抗氧化功能分析。结果显示,与对照组相比,产蛋高峰中期试验Ⅲ组蛋鸡的产蛋率、平均蛋重均显著提高,料蛋比显著降低（P<0.05）;鸡蛋哈夫单位、蛋壳颜色、蛋壳强度、蛋黄颜色、蛋清粗蛋白质含量、蛋黄粗蛋白质和粗脂肪含量均显著升高（P<0.05）,蛋清中必需氨基酸Leu、Lys、Met、Trp、Phe、Thr、Val和His及非必需氨基酸Ala、Asp、Glu、Pro和Tyr水平也显著增加（P<0.05）;试验Ⅳ组蛋鸡的蛋壳颜色、蛋壳强度、哈夫单位和蛋清粗蛋白质含量均显著提高（P<0.05）,蛋清中必需氨基酸Ile、Gly、Arg和非必需氨基酸Cys、Ser水平均显著增加（P<0.05）;试验Ⅰ~Ⅳ组蛋鸡蛋黄、蛋清中硒含量均显著增加（P<0.05）。同时,与对照组相比,产蛋高峰中期试验Ⅲ组蛋鸡血清MDA含量显著下降（P<0.05）,WBC数量、血清IFN-γ和IL-2水平及T-AOC和T-SOD活性均显著升高（P<0.05）。结果表明,饲粮中联合添加酵母硒和适量的虫草粉能明显提高产蛋高峰中期蛋鸡的产蛋性能和鸡蛋品质,增强机体免疫力和抗氧化能力,以0.1 mg/kg酵母硒联合添加0.3%虫草粉的效果最佳。 相似文献
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《The Journal of Applied Poultry Research》2017,26(1):9-22
Using locally produced feedstuffs for poultry production in developing countries can greatly lower production costs. Pearl millet is a drought-resistant plant that produces a nutritious grain. Its cultivation in Mali spans thousands of years, but the suitability of the millet grain currently produced in Mali for poultry production is unknown. Therefore, the nutrient composition of 7 different, widely available varieties of pearl millet grown in Mali was assessed before completing experiments in which laying hens or broilers were fed diets containing 0, 14, 28, or 43% whole pearl millet. The 7 varieties of pearl millet grown in different regions of Mali all had protein concentrations that were better than corn and had apparent digestible amino acid coefficients similar to corn. The nitrogen-corrected true metabolizable energy values ranged from 3,395 to 3,738 Kcal/kg on an as-is basis. Egg production and egg weight did not differ between the hens fed the different levels of millet through out a 16-wk experiment. Broilers fed the highest level of pearl millet from 1 to 42 d of age gained less (3.088 versus 2.949 kg) body weight than those fed the control diet. However, body weight gains did not differ between the broilers fed the control diet and the diets containing 14 or 28% whole millet. The results indicate that Malian-grown pearl millet would be an effective feed ingredient for poultry production and that this small seed could be added in whole form into laying hen and broiler diets. 相似文献
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MacLachlan DJ 《British poultry science》2008,49(3):290-298
1. Implementation of Good Manufacturing Practice and HACCP (Hazard Analysis Critical Control Points) in the production of poultry feed requires efficient tools for profiling risks associated with pesticide use in the production of crops for feed. 2. This paper describes a simple model that may be of use in the first tiers of risk profiling of feeds. 3. The model adequately reproduced the pattern of residues in fat and eggs of laying hens dosed with a selection of lipophilic pesticides that may be used in the production of crops for poultry feeds: deltamethrin, diflubenzuron, fipronil, lindane, piperonyl butoxide and spinosad. 4. Simulations suggest results derived from studies on laying chickens can be extrapolated to other laying birds. 5. Poultry meat production systems focus on maximising growth of birds giving rise to significant potential for dilution of residues that transfer to fat from feed. 6. Simulations of residues in fat of chickens, ducks, geese and turkeys exposed to a lipophilic pesticide with an elimination half-life of one day at 10 mg/kg body weight/d from hatching to typical market ages suggest residues in fat that are highest in turkeys > chickens > geese > ducks. 7. The model is of use in interpreting published dosing studies and predicting likely residues in birds at times after last exposure/dosing. 相似文献