不同品种鸡蛋蛋黄中胆固醇含量的比较

对土鸡蛋和普通鸡蛋蛋黄中胆固醇的含量进行了比较研究.试验结果表明,土鸡蛋蛋黄中的胆固醇含量(21.08 mg/g) 著高于普通鸡蛋(16.69 mg/g)(P<0.05).建议每人每天所食用鸡蛋的量应以不超过2枚为宜.     

营养成分对鸡蛋胆固醇含量的影响

近年来,随着人们消费水平的提高,鸡蛋中胆固醇、多不饱和脂肪酸(PUFA)的含量以及蛋黄颜色的深浅已成为衡量蛋品质的重要指标,直接影响着市场的需求。研究发现,通过营养代谢调控手段,能改善蛋品质,生产出胆固醇含量低、PUFA含量高的鸡蛋。现将影响鸡蛋胆固醇含量的因素报道如下。1能量物质大量研究表明,蛋鸡日粮中能量或脂肪的浓度过高会使鸡蛋中胆固醇的含量增加。当机体能量贮备足够时,过量摄入能量会表现为体重增加,胆固醇的生物合成提高。2脂类由于日粮中脂肪和胆固醇与家禽机体胆固醇的代谢密切相关,饲料中脂肪、脂肪酸的组成和含量…     

日粮中不同牛磺酸水平对蛋鸡体内脂类代谢的影响

将504只59周龄海兰褐蛋鸡随机分为7组,每组3个重复,每个重复24只鸡。在各组鸡饲粮中分别添加0%、0.005%、0.01%、0.02%、0.04%、0.08%、0.16%的牛磺酸,研究牛磺酸对蛋鸡血清、肝脏及蛋黄脂类代谢的影响。试验结果表明:1)日粮中添加牛磺酸能够显著降低68周龄蛋鸡血清总胆固醇、甘油三酯含量(P<0.05);显著提高64周龄及68周龄蛋鸡血清高密度脂蛋白胆固醇含量(P<0.05)。2)添加牛磺酸可显著降低68周龄蛋鸡肝脏胆固醇含量(P<0.05)。3)日粮中添加牛磺酸可降低68周龄蛋鸡蛋黄胆固醇含量但差异不显著(P>0.05);显著降低68周龄末产蛋鸡蛋黄中棕榈酸及硬脂酸含量(P<0.05);显著增加蛋黄油酸含量(P<0.05);极显著增加蛋黄亚油酸含量(P<0.01)。说明蛋鸡日粮中添加牛磺酸可以改善蛋黄脂肪组成。4)综合本试验各项结果,以添加0.005%水平牛磺酸调节蛋鸡脂类代谢的效果最佳。     

饲养方式及日粮对固始鸡蛋胆固醇含量的影响

试验选用630只12周龄的固始蛋用母鸡,按平均体质量分成7组,每组3个重复。第1～6组放养,分别饲喂6种不同配方的日粮;第7组笼养,饲喂日粮与第1组试鸡相同。结果表明,第1和第7组每克蛋黄胆固醇含量及每枚鸡蛋胆固醇含量差异不显著,说明饲养方式对降低鸡蛋胆固醇含量无明显效果,但放养表现出一定的优势,放养鸡蛋黄比例比笼养鸡低,放养鸡每枚鸡蛋胆固醇含量比笼养鸡低7.35%;对放养鸡而言,当日粮中蛋白质水平为13.77%时,每克蛋黄胆固醇含量随日粮中代谢能水平的提高而上升,提高日粮中蛋白质水平将显著提高蛋黄中胆固醇浓度。     

不同苜蓿草粉水平对产蛋鸡蛋黄胆固醇含量影响的研究

选择健康35周龄新罗曼商品代蛋鸡768只,采用2×4因子试验设计,随机分为8个处理组,每组3个重复,每个重复32只,分别在饲粮中添加0,3%,5%,7%的紫花苜蓿草粉和1.6%和2.4%的油脂,试验期60 d,观测苜蓿草粉和油脂对鸡蛋蛋黄重、蛋黄相对重、每克蛋黄胆固醇含量以及每枚鸡蛋中胆固醇含量的影响.结果表明:1)添加苜蓿草粉和油脂后,对蛋黄相对重无显著影响(P＞0.05);蛋黄重有显著增加,其中低油脂组中7%草粉添加组蛋黄重极显著高于不添加组(P＜0.01),各添加组之间差异不显著;高油脂组中各添加组之间无显著差异;每g蛋黄胆固醇含量有较大降低,添加草粉后,各试验组较不添加组极显著降低每g蛋黄中胆固醇含量(P＜0.01);每枚蛋中胆固醇含量有显著降低,其中高油脂组中5%和7%草粉添加组蛋黄重极显著高于不添加组(P＜0.01),各添加组之间差异不显著.二者的交互作用中,苜蓿水平对鸡蛋中胆固醇的影响高于油脂水平.2)随着苜蓿草粉添加水平的增加,每g蛋黄中胆固醇含量和鸡蛋中胆固醇含量逐渐降低,每g蛋黄中胆固醇含量在前30 d下降较快,随后逐渐降低,试验至45 d时趋于平稳.     

日粮中添加紫苏籽对鸡蛋黄多不饱和脂肪酸含量影响的研究

玉米 豆粕型蛋鸡日粮中分别加入 8% ,1 2 % ,1 6 % ,2 0 %的紫苏 ,研究鸡蛋黄多不饱和脂肪酸 (PUFA)的含量及其比例变化 ,分析蛋黄胆固醇含量。结果表明 :添加 8% ,1 2 % ,1 6% ,2 0 %的紫苏 ,蛋黄PUFA由添加前的 1 7 0 3 %分别提高到 2 0 42 % ,2 3 61 % ,2 4 0 7% ,2 4 62 % ,添加 1 2 % ,1 6 % ,2 0 %紫苏组与对照组间差异极显著 (P <0 0 1 )。蛋黄脂肪中ω - 3含量分别提高到 6 88% ,8 72 % ,9 86%和 9 95 % ,添加组与对照组 (1 1 2 % )相比差异极显著 (P <0 0 1 )。每枚鸡蛋中ω - 3的绝对含量由添加前的 52 83mg增加到 2 99 82 ,394 89,436 77,452 97mg。ω - 6/ω - 3的比例由添加前的 1 3 0 7,分别降到 1 98,1 67,1 44,1 47。PUFA/SFA (饱和脂肪酸 )由对照组的 0 38升高到 0 68(2 0 %组 )。蛋黄胆固醇含量无明显变化。紫苏可提高PUFA、ω - 3含量 ,改善ω - 6/ω - 3和PUFA/SFA的比例 ,降低生产成本 ,因此建议在饲粮中添加 1 6 %紫苏。     

日粮不同种类脂肪酸对青壳Ⅱ号蛋鸭蛋黄胆固醇含量和肌肉pH值的影响

为了研究日粮不同种类的脂肪酸对蛋鸭蛋黄中胆固醇含量和肉质pH值的影响,试验将264只17周龄健康、体重相近的青壳Ⅱ号蛋鸭随机分成4组,每组66只(含3个重复,每个重复22只)进行饲养试验。对照组饲喂基础日粮,试验组分为鱼油组(含3%鱼油)、葵花籽油组(含2.5%葵花籽油)、高脂组(含3%棕榈油+2%牛油),试验期为8周。结果表明:与对照组相比,鱼油组和葵花籽油组,蛋黄胆固醇(TC)含量显著下降(P0.05),而高脂组TC含量显著提高;此外,鱼油组和葵花籽油组对肉质pH值在1 h内无显著差异(P0.05),在随后的48 h内pH值显著降低(P0.05);而高脂组48 h内pH值与其它各组相比有升高趋势。     

日粮中不同铜源及添加水平对产蛋鸡生产性能及蛋黄胆固醇含量的影响

高铜(硫酸铜)能降低肉鸡血浆和肌肉中胆固醇的含量.在其他动物上的研究也表明,缺铜引起的高胆固醇血症是一个与动物种类无关的普遍现象,缺铜时机体的胆固醇合成以及组织沉积均增加.     

日粮月见草籽对鹌鹑蛋黄中脂肪酸的作用

通过饲养试验,在基础日粮中分别添加0%、8%1、0%、12%、15%的月见草籽(磨碎),研究不同添加量对鹌鹑蛋黄中脂肪酸的影响。选用150羽健康1日龄鹌鹑随机分成5组,每组设3个重复,每个重复10羽鹌鹑进行为期50 d的饲养。结果显示:添加月见草籽可明显增加鹌鹑蛋黄中不饱和脂肪酸(PUFA)的含量(P<0.05),尤其是C18:2的含量显著高于对照组(P<0.05)。蛋黄中ω-6含量和日粮中月见草籽添加量之间呈现出显著的相关关系(P<0.05),其关系可用一次回归式Y=3.688 7 X+42.038(r=0.958 9)来表示。     

亚麻籽脂肪酸在蛋黄中的沉积效果

Greenland岛的爱斯基摩人摄入大量脂肪,但很少发生心脑血管疾病,营养学家推断廿碳五烯酸（Eicosapentaenoic acid,20:5ω-3 EPA）和廿二碳六烯酸（Docosahexaenoicacid,22:6ω-3 DHA）可减少心脑血管疾病发生,从此ω-3多不饱和脂肪酸（ω-3PUFA）的营养,引起了人们的重视。研究表明,ω-3脂肪酸是大脑发育所必需的物质,具有抗动脉硬化、抗血栓、降血脂、抗炎性反应等保健作用。ω-3脂肪酸的作用,提示蛋鸡生产者生产富含ω-3不饱和脂肪酸的保健鸡蛋,一方面可以提高鸡蛋的营养价值,另一方面可以缓解因鸡蛋中的高胆固醇（200-250mg胆固醇/枚）带给老年消费者的后顾之忧。尽管鸡蛋中的胆固醇能否使血中胆固醇升高仍有争议,但营养学家推荐每天     

泊洛沙姆-辛酸法对鸡卵黄脱脂条件的研究

本文就泊洛沙姆浓度、辛酸浓度、泊洛沙姆沉淀法沉淀离心条件对泊洛沙姆-辛酸法对鸡卵黄脱脂的影响进行了探讨。实验结果表明:泊洛沙姆浓度、辛酸浓度分别对卵黄脱脂存在不同程度影响,卵黄稀释液沉淀离心条件对卵黄脱脂影响不大。蛋黄稀释液不经离心直接纱布过滤,辛酸浓度为0.2%,泊洛沙姆浓度分别为0.6%、0.8%、1%、1.2%、1.4%、1.6%、1.8%的7个处理中,以1.2%浓度的提取效果最好;泊洛沙姆浓度为1.2%,辛酸浓度为0.2%,蛋黄稀释液经离心处理和纱布过滤处理对卵黄脱脂影响不大;泊洛沙姆浓度为1.2%,蛋黄稀释液纱布过滤处理,辛酸浓度分别为0、0.1%、0.2%、0.3%、0.4%、0.5%的6个处理中,以0.2%浓度的提取效果最好。     

北京油鸡杂交效果的研究

为培育优质北京油鸡配套系提供理论依据,试验采用北京油鸡纯系(Y系)与北京油鸡合成品系(G系)进行正反杂交,观测亲本及其杂交组合的体尺、外貌性状、生长性能、屠宰性能和肉质性状,并比较各性状的杂种优势。结果表明:Y系与G系的正反交组合不仅在生长性能、屠宰性能及相应的肉质性能上具有显著的杂种优势,而且杂交后代能够很好地保持北京油鸡的外貌特征;在正反交组合中,以Y系为父系、G系为母系的正交组合(YG)表现的更为优秀。说明北京油鸡在优质鸡育种和杂交利用上更适合做父系,以充分利用其优良的遗传品质。     

使鸡蛋脂质中ω-3脂肪酸富集的途径

目前许多研究已证明鸡蛋脂质中含有一些多不饱合脂肪酸(PUFA),特别是ω-3多不饱和脂肪酸,对人的健康是十分有益的,特别对大脑、视网膜及精子的功能至关重要.     

Effect of type and level of fish oil supplementation on yolk fat composition and n-3 fatty acids retention efficiency in laying hens

1. Laying hen performance and yolk fat fatty acid (FA) concentrations were evaluated with respect to the inclusion in the diet of different sources and levels of marine fish oil (MFO). 2. Twelve diets were arranged factorially, with three sources (MFO1, MFO2_EPA, MFO3_DHA) and four levels of inclusion (15, 30, 45 and 60 g/kg) of MFO. 3. Type of diet had little effect on egg production traits, although laying rate and shell thickness slightly decreased at the highest level of MFO supplementation. 4. An increase in level of inclusion of MFO from 15 to 60 g/kg linearly increased concentrations of C20:5 n-3, C22:5 n-3, C22:6 n-3 and total n-3 FA in yolk fat, but greatly impaired their efficiencies of deposition (g retained/g ingested). 5. An interaction between type and dietary concentration of MFO was found, as the reduction in efficiency of retention of n-3 FA in egg fat with level of MFO was less when the proportion of n-3 in total FA decreased or when that of DHA in total n-3 FA increased. 6. MFO3_ DHA was more efficiently used for total n-3 FA yolk deposition than MFO2_EPA at a similar total n-3 FA intake. 7. Dietary inclusion of MFO reduced LC n-6 FA yolk fat content, which additionally decreased the ratio between total n-6 and total n-3 FA in egg fat. 8. Regression equations were calculated in order to predict efficiency of retention and n-3 FA concentration of yolk fat in the range of diets studied.     

鸡品种与日粮营养水平对脂肪酸的影响

试验对肉鸡、肉杂鸡、盐津鸟鸡、武定鸡和茶花鸡肌肉脂肪酸含量分析结果表明,地方鸡和国内培育鸡种（肉杂鸡）含较高多不饱和脂肪酸（PUFA）,尤其以茶花鸡的相对含量最高。采食低营养水平日粮其胸肌饱和脂肪酸含量最高,随着日粮营养水平的提高,不饱和脂肪酸有上升的趋势;日粮营养水平对多不饱和脂肪酸C18：2和C18：3的含量影响不显著。但随着日粮营养水平的提高,C18：2和C18：3的含量逐渐增加。     

Effect of maternal corticosterone on utilisation of residual yolk sac fatty acids by developing broiler embryo

1. Increased concentrations of maternal corticosterone are deposited into egg yolk under stress conditions. This experiment investigated the effect of maternal corticosterone on yolk and yolk sac fatty acid profiles of eggs and developing broiler embryos. 2. At 42 weeks of age, 200 broiler breeder females were randomly divided into two groups: maternal corticosterone (MC): 2 mg/hen/d of corticosterone dissolved in 1 mL of 99% ethanol and mixed in the individual daily feed for a 14 d period, and control: 1 mL of ethanol added to the individual daily feed. Hens were inseminated, and eggs were collected daily from d 3 of corticosterone feeding to d 14 and incubated. Fatty acid profiles of egg yolk and yolk sac were analysed before incubation and at 12, 14, 18 and 21 d of incubation. 3. Yolk corticosterone concentrations were greater in MC eggs. Before incubation, eggs from MC had lower DHA (22 : 6 n-3) but higher stearic (18 : 0) and dihomo-gamma linolenic (20 : 3 n-6 Cis 8,11,14) acid content compared with the control. 4. Higher concentrations of stearic (18 : 0), elaidic (18 : 1 tr n-9), eicosenoic (20 : 1 n-9), eicosadienoic (20 : 2 n-6), dihomo-gamma linoleic (20 : 3 n-6) and arachidonic (20 : 4 n-6) acids and lower concentrations of myristic (14 : 0), palmitoleic (16 : 1 n-7), linoleic (18 : 2 n-6) and DHA (22 : 6 n-3) were found at different periods of incubation in the residual yolk sac of MC than from controls. 5. The results suggest that the preferentially selective absorption of fatty acids is related to specific tissue requirements.     

用禽卵大量制备多克隆抗体的研究进展

禽类能将血清中免疫球蛋白主动传递给子代，而发挥被动免疫保护功能，禽卵卵黄中的免疫球蛋白只有ＩｇＧ。由于卵黄免疫球蛋白具有许多优点，如：不与ＳＰＡ，ＳＰＧ或哺乳动物Ｆｃ受体片段结合，以及不识别类风湿因子等。而且抗体制备过程简单、产量高。因此适宜于多种多克隆抗体的大量制备。本文就这方面的研究加以综述。     

Histochemical observations on the enzymes of chicken yolk sac membrane

In the endodermal cells of the yolk sac membrane of chicken embryos incubated for 12 to 18 d, the activity of glucose‐6‐phosphatase (G‐6‐Pase) was high, the activity of acid phosphatase (Acid Pase) was moderate, the activities of lactate dehydrogenase (LDH) and of glyceraldehyde‐3‐phosphate dehydrogenase (G‐3‐PDH) were low, and succinate dehydrogenase (SDH) and alkaline phosphatase (Alk Pase) activities were not detected. On the day before hatching, however, SDH became evident with low activity, and the activities of Acid Pase, LDH and G‐3‐PDH increased and remained higher until the day after. Five days after hatching, there were marked decreases in the activities of all the enzymes except SDH. Alk Pase was not detected at any time. The function of the yolk sac endo‐derm in the absorption of yolk is discussed in the light of these observations.