饲粮中添加微藻DHA和ALA对蛋黄脂肪酸构成及蛋黄胆固醇、三酰甘油的影响

试验旨在研究饲粮中添加微藻二十二碳六烯酸(DHA)和α-亚麻酸(ALA)对蛋黄脂肪酸成分以及蛋黄胆固醇、甘油三酯的影响。方法:选取300日龄海兰褐蛋鸡576只,随机分为3个处理,每个处理3个重复,每重复64只鸡。对照组饲喂基础饲粮,试验组添加0.2%DHA和0.3%ALA,试验期42 d。结果表明:添加DHA和ALA的鸡蛋,多不饱和脂肪酸(PUFA)的含量均有显著提高(P0.05);添加DHA比添加ALA更能显著增加蛋黄中的二十二碳六烯酸(P0.05),更具降低胆固醇等作用。2个添加组均能显著增加n-3多不饱和脂肪酸(n-3PUFA)的含量(P0.05),并且添加DHA或ALA均能降低n-6/n-3的比值;添加DHA和ALA都可以显著降低蛋黄中的总胆固醇(TC)和总三酰甘油(TG)值(P0.05);添加DHA能更有效的降低血清TG。     

2%裂殖壶菌粉蛋鸡饲粮中添加胆碱和磷脂可增加蛋黄中二十二碳六烯酸的富集

本试验旨在研究2%裂殖壶菌粉蛋鸡饲粮中添加胆碱和磷脂对蛋鸡生产性能、蛋品质和蛋黄脂肪酸组成的影响。选用360只28周龄的海兰灰产蛋鸡,随机分为5个处理,每个处理6个重复,每个重复12只鸡。基础饲粮含有2%裂殖壶菌粉(二十二碳六烯酸(DHA),137.09mg/g)。对照组饲喂基础饲粮,其他4个处理组在基础饲粮上分别添加1,000mg/kg胆碱(CHO)、1,000mg/kg乙醇胺(MEA)、1,000mg/kg溶血磷脂酰胆碱(LPC)和500mg/kgLPC+500mg/kgMEA(LPC+MEA)。所有饲粮等能(代谢能,11.15MJ/kg)等氮(粗蛋白,16.60%)。试验期28天。结果表明:各处理饲粮对蛋鸡的生产性能和蛋品质无显著影响(P0.05)。饲喂28天后,饲粮添加LPC显著降低了蛋黄单不饱和脂肪酸(MUFA)的含量(P0.01),提高了多不饱和脂肪酸(PUFA)含量(P0.05)。与对照组相比,饲粮添加LPC有增加蛋黄n-6PUFA含量的趋势(P=0.07);饲粮添加CHO和LPC显著提高了蛋黄n-3PUFA和DHA含量,降低n-6PUFA与n-3PUFA的比例(n-6/n-3)(P0.01)。饲喂14天后,蛋黄DHA含量达到最大值,且蛋黄DHA含量在CHO和LPC组高于其他各组(P0.05)。结论:2%裂殖壶菌粉蛋鸡饲粮中添加胆碱,饲喂周期达到14天后,可增加蛋黄n-3PUFA和DHA含量,且对蛋鸡的生产性能、蛋品质和鸡蛋组分无不良影响。     

日粮中添加亚麻籽油对鸡蛋脂肪酸组成和风味的影响

试验旨在研究日粮中添加亚麻籽油对蛋鸡生产性能、蛋品质、蛋黄脂肪酸组成及鸡蛋风味的影响。选取40周龄海兰灰商品代蛋鸡288只,随机分为4组,每组8个重复,每个重复9只鸡。设计分别添加0、0.5%、1.0%和3.0%亚麻籽油的4种等能等氮日粮。预试期1周,正试期4周。结果显示:(1)日粮中添加0.5%、1.0%、3.0%亚麻籽油对产蛋鸡生产性能、蛋品质均无显著影响(P0.05);(2)亚麻籽油可显著提高蛋黄中α-亚麻酸(ALA)、二十碳五烯酸(EPA)、二十二碳六烯酸(DHA)及总n-3多不饱和脂肪酸(PUFA)含量,且其随亚麻籽油添加水平增加呈线性和二次变化(P0.05);(3)3.0%亚麻籽油组显著降低了蛋黄气味及滋味评分,同时显著增强了蛋黄鱼腥气味及滋味评分(P0.05),而蛋黄总体接受度显著降低(P0.05),且其均随亚麻籽油添加水平增加呈线性和二次变化(P0.05);(4)鸡蛋蛋黄总n-3PUFA含量与鱼腥气味、滋味间具有显著相关性(P0.05),且鸡蛋蛋黄接受度随n-3PUFA含量增加而降低(R2=0.801)。综上所述,日粮添加亚麻籽油可提高蛋黄总n-3PUFA含量,但添加量过高时对鸡蛋风味产生不良影响导致总体接受度下降;蛋黄总n-3PUFA含量不高于21.26mg/g时,可接受度评分大于5分,鸡蛋感官品质在可接受范围内。     

饲粮脂肪对山麻鸭蛋品质和血清、蛋黄脂质生化指标的影响

本试验旨在研究饲粮不同水平的多不饱和脂肪酸对山麻鸭蛋品质以及血清和蛋黄脂质生化指标的影响。试验选择585只产蛋期山麻鸭,采用4×4的两因子随机试验设计,分别饲喂在基础饲粮中添加三个不同水平(0.5%、1%和2%)的鱼油、亚麻籽油、菜籽油和牛脂的试验饲粮28天。试验结果表明,饲粮脂肪来源和水平对蛋品质无显著影响。鱼油、亚麻籽油和菜籽油显著降低了山麻鸭蛋黄胆固醇、饱和脂肪酸和单不饱和脂肪酸的比例,显著提高了蛋黄多不饱和脂肪酸、ω-6多不饱和脂肪酸、ω-3多不饱和脂肪酸、二十碳五烯酸和二十二碳六烯酸的比例。添加鱼油、亚麻籽油和油菜籽油显著提高饲粮DHA和EPA的含量。与对照组相比,鱼油显著提高了山麻鸭血清低密度脂蛋白-胆固醇的浓度,亚麻籽油显著降低了其血清总胆固醇和极低密度脂蛋白-胆固醇的浓度,菜籽油显著降低了其血清总胆固醇和低密度脂蛋白浓度,提高了其极低密度脂蛋白-胆固醇浓度,牛脂显著提高了其血清低密底脂蛋白-胆固醇浓度。综上,添加鱼油、亚麻籽油和菜籽油的富含不饱和脂肪酸饲粮未显著影响山麻鸭蛋品质,但可提高山麻鸭蛋黄的多不饱和脂肪酸比例、降低蛋黄胆固醇浓度和改变血清脂质参数。     

陈化玉米对蛋鸡生产性能和蛋品质的影响

试验研究了陈化玉米和添加大豆油对蛋鸡生产性能、蛋品质、蛋黄胆固醇和脂肪酸分布及血清参数的影响。试验采用2×2因子设计,2种玉米(正常和陈化)和2种大豆油水平(0和2%),一共4种日粮。试验动物为50周龄左右的商品蛋鸡共960只,随机分为4组,每组5个重复,每个重复48只,试验为期8周。结果 :日粮处理对鸡蛋产量、鸡蛋重量、料蛋比和鸡蛋质量无显著影响(P 0.05)。日粮添加陈化玉米显著提高了血清胆酸盐和单不饱和脂肪酸水平(P 0.05),同时显著降低了蛋鸡血清胆固醇水平、蛋黄颜色、多不饱和脂肪酸和n-6多不饱和脂肪酸水平(P 0.05)。日粮添加大豆油显著增加了血清总胆固醇甘油三酯、蛋黄n-6和n-3多不饱和脂肪酸及不饱和脂肪酸水平(P 0.05),但蛋鸡平均日采食量、血清极低密度脂蛋白、饱和脂肪酸和单不饱和脂肪酸含量显著降低(P 0.05)。综上所述,蛋鸡使用陈化玉米对生产性能无显著影响,但使蛋黄颜色变浅,蛋黄中多不饱和脂肪酸和n-6多不饱和脂肪酸含量降低。     

饲粮中添加微藻和亚麻籽提高鸡蛋黄中ω-3多不饱和脂肪酸含量对比研究

本试验旨在比较饲粮中添加微藻和亚麻籽对蛋鸡生产性能、蛋品质、蛋黄脂肪酸组成的影响及蛋黄ω-3多不饱和脂肪酸(PUFA)沉积规律。选取37周龄健康、产蛋率和体形相近的罗曼蛋鸡216只,随机分为3个组,每组6个重复,每重复12只。对照组饲喂玉米-豆粕型基础饲粮,2个试验组分别饲喂基础饲粮中添加8%微藻(微藻组)和8%亚麻籽(亚麻籽组)的饲粮。试验期4周。结果表明:1)与对照组相比,微藻组和亚麻籽组的产蛋率、平均日采食量、平均蛋重和料蛋比均无显著差异(P0.05)。2)与对照组相比,微藻组和亚麻籽组的蛋重、蛋黄重、蛋黄比例、蛋白重、蛋白比例、蛋白高度和哈氏单位均无显著差异(P0.05);但贮存时间延长可极显著降低哈氏单位和蛋白高度(P0.01),且微藻组和亚麻籽组的降低程度高于对照组;微藻组蛋黄颜色评分极显著高于对照组和亚麻籽组(P0.01)。3)与对照组相比,微藻组和亚麻籽组蛋黄ω-3 PUFA含量均极显著提高(P0.01),ω-6 PUFA含量和ω-6/ω-3极显著降低(P0.01)。4)微藻组和亚麻籽组蛋黄中二十二碳六烯酸(DHA)、ω-3PUFA含量均第13天富集饱和,后出现缓慢降低趋势。由此可见,饲粮中添加微藻和亚麻籽均可生产富含ω-3 PUFA鸡蛋,最佳时间为第13天后,并且对蛋鸡生产性能和蛋品质无不良影响,但富含ω-3PUFA鸡蛋不易贮存。     

亚麻籽对鸡蛋中脂肪酸富集及蛋品质的影响

本试验旨在探讨日粮中亚麻籽添加水平和添加时间对蛋中n-3多不饱和脂肪酸的富集以及蛋品质的影响。选取46周龄京粉1号蛋鸡1 344只,随机分为4个组,每组6个重复,每个重复56只。4个处理组日粮中亚麻籽的添加水平分别为0%(对照组)、5%、10%、15%。试验期60 d。试验第10、20、30、45、60天测定蛋中α-亚麻酸、二十碳五烯酸(EPA)、二十二碳六烯酸(DHA)等n-3多不饱和脂肪酸(n-3PUFA)含量。第30、60天测定蛋壳强度、蛋黄色度和哈氏单位。结果表明:亚麻籽的添加水平、时间以及二者互作均对蛋中n-3PUFA的富集产生显著影响,蛋中n-3PUFA含量随着亚麻籽添加水平和添加时间增加呈上升趋势,随后达到稳定;5%亚麻籽组中鸡蛋DHA含量最高,其他脂肪酸含量以15%亚麻籽组最高;蛋中EPA含量在20 d达到最高,其他脂肪酸在30 d达到最高;蛋黄色度随着日粮中亚麻籽添加水平升高而显著降低,其他蛋品质指标无显著变化。由此表明,给蛋鸡饲喂含15%亚麻籽日粮30 d以上,可获得理想n-3PUFA富集鸡蛋,但要保证日粮色素水平稳定。     

Meta分析法研究亚麻籽对蛋黄中多不饱和脂肪酸的影响

为研究蛋鸡日粮中添加亚麻籽对蛋黄中多不饱和脂肪酸富集的影响,根据相关标准,采用人工和系统的检索方法检索相关文章,并用荟萃分析(Meta-analysis)的方法分析计算合并标准均数差(SMD)及95%置信区间(95%CI)。通过检索与筛选,共有8篇文章21个试验被纳入,共包括1390个研究对象。Meta分析的结果显示:蛋黄中亚麻酸(ALA)、二十二碳六烯酸(DHA)、亚油酸(LA)、总n-3多不饱和脂肪酸(n-3PUFA)、花生四烯酸(AA)、总n-6多不饱和脂肪酸(n-6PUFA)、n-6PUFA/n-3PUFA的SMD和95%CI分别为17.51(13.34,21.69)、5.39(4.22,6.55)、0.42(-0.39,1.23)、8.86(7.59,10.14)、-1.62(-2.54,-0.70)、-0.44(-0.97,0.08)和-5.22(-6.62,-3.82);混合线性模型的结果显示:DHA和n-3PUFA的异质性来源为亚麻籽添加剂量,蛋黄中ALA、AA、LA和n-6PUFA/n-3PUFA的异质性来源为亚麻籽的添加剂量和蛋鸡产蛋周龄。由分析结果可知,蛋鸡日粮中添加亚麻籽能显著提高蛋黄中的ALA、DHA及n-3PUFA的含量并能显著降低AA和n-6PUFA/n-3PUFA的水平,且富集水平受到亚麻籽添加剂量和蛋鸡产蛋周龄的影响。     

亚麻籽饲粮中添加不同水平酵母硒对蛋鸡肝脏抗氧化能力、蛋黄脂肪酸组成和蛋中硒含量的影响

本试验旨在研究在亚麻籽饲粮中添加不同水平酵母硒对蛋鸡生产性能、肝脏抗氧化能力、蛋品质、蛋黄脂肪酸组成和蛋中硒含量的影响。采用单因素试验设计,选取28周龄、体重[(1.99±0.05)kg]和产蛋率[(88.42±3.57)%]接近的海兰褐蛋鸡360只,随机分为4组,每组6个重复,每个重复15只鸡。各组蛋鸡分别饲喂在含15%膨化亚麻籽基础饲粮中添加0.3(Se_(0.3)组)、0.6(Se_(0.6)组)、0.9(Se_(0.9)组)和1.2 mg/kg(以硒计)酵母硒(Se_(1.2)组)的试验饲粮。预试期2周,正试期12周。结果显示:1)在亚麻籽饲粮中添加不同水平酵母硒对蛋鸡的生产性能和蛋品质均无显著影响(P0.05)。2)与Se_(0.3)组相比,Se_(1.2)组肝脏总抗氧化能力(T-AOC)显著降低(P0.05),Se_(0.9)组和Se_(1.2)组肝脏总超氧化物歧化酶(T-SOD)活性显著降低(P0.05)。随着饲粮中酵母硒添加水平的升高,肝脏中谷胱甘肽过氧化物酶(GSH-Px)活性有增加的趋势(P=0.094)。此外,与Se_(0.3)组相比,Se_(0.6)组、Se_(0.9)组和Se_(1.2)组肝脏丙二醛(MDA)含量均显著降低(P0.05)。3)在亚麻籽饲粮中添加不同水平酵母硒对蛋黄脂肪酸组成和ω-3多不饱和脂肪酸(PUFA)含量均无显著影响(P0.05),各组蛋黄中ω-3 PUFA含量均高于41 mg/g(干物质基础)。4)鸡蛋中硒含量随着饲粮酵母硒添加水平的升高而显著增加(P0.05)。由此得出,本试验条件下,在亚麻籽饲粮中添加不同水平的酵母硒对蛋鸡的生产性能和蛋品质无显著影响,但添加0.6 mg/kg(以硒计)酵母硒可提高蛋鸡肝脏的抗氧化能力。鸡蛋中硒含量随着饲粮酵母硒添加水平的升高而显著增加,并在此基础上进一步达到硒和ω-3 PUFA同时富集于鸡蛋中的效果。     

日粮多不饱和脂肪酸类型对蛋鸡生产性能和蛋黄脂肪酸富集的影响

将135只26周龄海兰褐商品蛋鸡随机分为3个处理,分别饲以3种日粮:n-3多不饱和脂肪酸日粮(PUFA)、n-6PUFA日粮和普通日粮研究PUFA类型对蛋鸡生产性能和蛋黄脂肪酸富集的影响。试验结果表明:n-3PUFA日粮使产蛋率和饲料效率显著(P<0.05)降低;n-6PUFA日粮组死亡率与其他组相比极显著(P<0.01)上升。两种PUFA日粮使蛋黄n-3PUFA及n-6PUFA含量显著(P<0.05)改变。结果表明:PUFA日粮能显著改变蛋黄PUFA的组成,可生产出n-3PUFA含量达到585mg/枚和n-6PUFA含量达到1595mg/枚的鸡蛋;但试验发现日粮中添加过多的亚麻籽和葵籽对蛋鸡生产性能有不良的影响(P<0.05)。     

日粮中添加亚麻籽油对鸡蛋脂肪酸组成和风味的影响

试验旨在研究日粮中添加亚麻籽油对蛋鸡生产性能、蛋品质、蛋黄脂肪酸组成及鸡蛋风味的影响。选取40周龄海兰灰商品代蛋鸡288只,随机分为4组,每组8个重复,每个重复9只鸡。设计分别添加0、0.5%、1.0%和3.0%亚麻籽油的4种等能等氮日粮。预试期1周,正试期4周。结果显示：①日粮中添加0.5%、1.0%、3.0%亚麻籽油对产蛋鸡生产性能、蛋品质均无显著影响（P>0.05）;②亚麻籽油可显著提高蛋黄中α-亚麻酸（ALA）、二十碳五烯酸（EPA）、二十二碳六烯酸（DHA）及总n-3多不饱和脂肪酸（PUFA）含量,且其随亚麻籽油添加水平增加呈线性和二次变化（P<0.05）;③3.0%亚麻籽油组显著降低了蛋黄气味及滋味评分,同时显著增强了蛋黄鱼腥气味及滋味评分（P<0.05）,而蛋黄总体接受度显著降低（P<0.05）,且其均随亚麻籽油添加水平增加呈线性和二次变化（P<0.05）;④鸡蛋蛋黄总n-3 PUFA含量与鱼腥气味、滋味间具有显著相关性（P<0.05）,且鸡蛋蛋黄接受度随n-3 PUFA含量增加而降低（R²=0.801）。综上所述,日粮添加亚麻籽油可提高蛋黄总n-3 PUFA含量,但添加量过高时对鸡蛋风味产生不良影响导致总体接受度下降;蛋黄总n-3 PUFA含量不高于21.26 mg/g时,可接受度评分大于5分,鸡蛋感官品质在可接受范围内。     

饲粮胆碱和裂殖壶菌油联合添加促进二十二碳六烯酸在鸡蛋卵黄中的富集

本试验旨在研究饲粮添加胆碱与裂殖壶菌油(Schizochytrium oil,SO)对鸡蛋卵黄脂质及二十二碳六烯酸(DHA)富集的影响。选取26周龄京红蛋鸡288只,分4组(每组6个重复,每重复12只鸡)。采用2×2因子试验设计,饲粮添加胆碱(500和1 000 mg/kg)和SO(0和0.5%)为2个主效应,共配制4种等氮等能饲粮。预试期1周,正试期8周。结果表明:1)试验期内,各组生产性能和蛋品质均无显著差异(P0.05)。2)各组卵黄中干物质、粗脂肪、胆固醇及甘油三酯含量均无显著差异(P0.05)。1 000 mg/kg胆碱组卵黄总磷脂含量显著高于500 mg/kg胆碱组(P0.05)。胆碱和SO对卵黄总磷脂含量有显著交互作用(P=0.04),1 000 mg/kg胆碱+0.5%SO组卵黄总磷脂含量最高。3)0.5%SO显著提高卵黄n-3多不饱和脂肪酸(PUFA)和DHA含量(P0.05),显著降低n-6 PUFA含量及n-6 PUFA/n-3 PUFA值(P0.05)。胆碱和SO对卵黄中n-3 PUFA(P0.001)、n-6 PUFA(P=0.01)及DHA(P0.001)含量和n-6 PUFA/n-3 PUFA值(P=0.01)有显著交互作用,1 000 mg/kg胆碱+0.5%SO组卵黄中n-3PUFA和DHA含量显著高于其他组(P0.05),且n-6 PUFA含量及n-6 PUFA/n-3 PUFA值显著低于其他组(P0.05)。综上,本试验条件下,饲粮中1 000 mg/kg胆碱和0.5%SO联合添加可促进卵黄DHA富集,且对蛋鸡生产性能和蛋品质无显著影响。     

Supplemental defatted microalgae affects egg and tissue fatty acid composition differently in laying hens fed diets containing corn and flaxseed oil

Effects of defatted microalgae (DFA) on fatty acid composition of eggs and tissues of hens have not been well studied. This experiment was to determine how low concentrations of supplemental DFA in the presence or absence of flaxseed oil (FO) altered fatty acid profiles of egg yolk, liver, adipose tissue, and plasma of layers. A total of 60 Shaver Leghorn layer hens (individually caged, 20-wk old) were allotted into 6 groups (n = 10) and fed a corn/soybean meal basal diet containing 0, 3, or 5% DFA and 0 (1.5% corn oil, CO) or 1.5% FO for 6 wk. BW, ADFI, egg production rate, and egg component weights were not affected by any of the dietary treatments at various time points, but egg yolk color was changed (P < 0.05) with increasing concentrations of DFA. The concentration of n-3 fatty acids in egg yolk and plasma were elevated by FO up to 9-fold (P < 0.05) starting at wk 1 or 2, and 39 to 83% (P < 0.05) by DFA. Supplemental DFA improved (P < 0.05) n-6/n-3 fatty acid ratios in egg yolk and plasma from 13 to 23 and 7 to 13, respectively, only in hens fed diets without FO. Fatty acid profiles of liver and adipose tissue (at wk 6) displayed responses to supplemental DFA and FO similar to those of egg yolk or plasma. In conclusion, supplemental 3 or 5% DFA caused moderate enrichments of n-3 fatty acids and decreased the n6/n3 fatty acid ratios of egg yolk and tissues in hens fed diets without FO.     

Long-Term Feeding of Conjugated Linoleic Acid and Fish Oil to Laying Hens: Effects on Hepatic Histopathology,Egg Quality,and Lipid Components

The present study was conducted to investigate the effect of long-term feeding of conjugated linoleic acid (CLA) and fish oil on egg quality characteristics, production performance, liver pathology, and egg fatty acid content of laying hens. Single Comb White Leghorn laying hens (n = 112), 21 wk old, were placed in cages and randomly assigned to 4 diets (28 hens/diet, 4 replicates of 7 hens) containing 3.0% yellow grease (control), 2.75% yellow grease + 0.25% CLA (YG-CLA), 2.5% yellow grease + 0.25% CLA + 0.25% fish oil (YG-CLA-FO), and 2.75% yellow grease + 0.25% fish oil (YG-FO). The experimental diets were fed for 12 mo. Eggs were collected daily for 12 mo. Feed consumption, hen-day egg production, and feed efficiency were monitored. At the end of the trial, hepatic tissue was collected for histopathology. No effect of diet was found on feed consumption, hen-day egg production, feed efficiency, egg weight, yolk weight, shell weight, or Haugh unit. The YG-CLA and YG-CLA-FO diets produced an increase in CLA and saturated fatty acids in the egg and liver tissue with a concomitant reduction in monounsaturated fatty acids (P < 0.05). Feeding YG-CLA-FO and YG-FO increased the n-3 fatty acids in egg yolk and liver of hens (P < 0.05). No difference was observed in the number of fat vacuoles in the liver tissue. The total fat content of hepatic and abdominal fat pads did not differ among treatments (P > 0.05). Regardless of the diet, as the hens aged, egg weight, yolk weight, and egg total fat increased, and shell weight decreased (P < 0.05). These data demonstrate that eggs with increased n-3 fatty acids and CLA can be generated by minor diet modifications without affecting the production performance or health of birds.     

The Effects of n-3 Fatty Acid Supplementation on Bleeding Time, Plasma Fatty Acid Composition, and In Vitro Platelet Aggregation in Cats

Dietary supplementation with fish and fish oils rich in the n-3 fatty acids eicosapentaenoic acid ( EPA ) and docosahexaenoic acid (DHA) has been shown to alter eicosanoid metabolism and impair platelet function in several species. As an initial step in evaluating the antithrombotic effect of these n-3 fatty acids in cats, purified EPA and DHA were administered daily to 8 clinically normal cats for 2 months. Platelet function was evaluated biweekly by determining mucosal bleeding time and in vitro platelet aggregation parameters. Plasma fatty acid profiles were obtained before fish oil supplementation and at the termination of the study. In spite of significant increases ( P < .0001) in the plasma concentrations of EPA and DHA after n-3 fatty acid supplementation, there were no significant changes in platelet aggregation or bleeding times. Although it is tempting, based on extrapolation of data from other species, to recommend dietary supplementation with fish oil for cats prone to arterial thromboembolism, these results indicate that administration of large doses of purified EPA and DHA once daily does not inhibit platelet function in normal cats and is unlikely to prevent thrombosis in cats with cardiovascular disease. Additional studies are recommended to ascertain whether more frequent administration of these purified n-3 fatty acids or continual feeding of diets high in n-3 fatty acid content will impair platelet function.     

饲粮中配合橡胶籽饼对蛋鸡蛋黄脂肪酸组成的影响

本试验通过在海兰褐蛋鸡饲粮中配合不同比例的橡胶籽饼,评价其对蛋黄脂肪酸组成及胆固醇含量的影响。选取72只25周龄的健康海兰褐蛋鸡,随机分成6个组,每组4个重复,每个重复3只鸡。对照组饲喂玉米-豆粕型基础饲粮,Ⅰ~Ⅴ组饲粮分别配合5.00%、10.00%、15.00%、20.00%和25.00%的橡胶籽饼。各组饲粮的营养水平一致。试验期6周。结果表明:饲粮中配合不同比例橡胶籽饼对蛋鸡蛋黄饱和脂肪酸(SFA)含量无显著影响(P0.05);但蛋黄亚油酸(LA)、α-亚麻酸(ALA)、二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)含量随饲粮橡胶籽饼配合比例的增加呈增加趋势,且各试验组蛋黄DHA含量与对照组相比差异显著(P0.05);随饲粮橡胶籽饼配合比例的增加,蛋黄总多不饱和脂肪酸(PUFA)、n-6 PUFA和n-3 PUFA含量呈增加趋势,n-6/n-3 PUFA呈降低趋势;各试验组蛋黄胆固醇含量与对照组相比差异不显著(P0.05),但均低于对照组。由此可见,饲粮中配合一定比例的橡胶籽饼能够获得较低的n-6/n-3PUFA,达到提高蛋黄总PUFA、n-6 PUFA和n-3 PUFA含量的效果。     

日粮中脂肪酸对羊牛猪肉中长链多不饱和脂肪酸和共轭亚油酸的影响

随着消费者健康意识的提高,越来越多的研究关注提高家养动物肉产品中多不饱和脂肪酸(PUFA)含量,尤其是n-3长链脂肪酸和共轭亚油酸(CLA)在羊、牛、猪肉肌内脂中的含量。研究结果表明通过添加鱼油或鱼粉能提高动物肉中n-3长链脂肪酸含量。富含亚麻油酸(LNA)的日粮能提高肉中LNA、二十碳五烯酸(EPA)和二十二碳五烯酸(DPA)水平,但大部分对肌肉中二十二碳六烯酸(DHA)水平没有影响。然而,在日粮中添加鱼油或鱼粉大部分能提高动物肌肉中DHA含量。大部分研究中提高n-3脂肪酸含量的同时n-6脂肪酸含量下降,这主要归因于试验组日粮中n-6脂肪酸降低。这样刚好可以使肉中两者比例更合理,但对多不饱和脂肪酸与饱和脂肪酸比例没什么影响。饲喂反刍动物富含n-3脂肪酸日粮(亚麻籽或加草料)、鱼油或富含LA的浓缩料可提高肌肉中c9t11CLA含量。牛肉、羊肉中c9t11CLA在总脂中含量介于0.2~1.0 g/100 g,不随营养因素提高到更高。相对应的,在单胃动物日粮中添加混合CLA油则显著提高CLA含量。     

Lipid profile in eggs of Araucana hens compared with Lohmann Selected Leghorn and ISA Brown hens given diets with different fat sources

1. In a cross-over trial, the egg cholesterol and fatty acid composition of Araucana hens was compared with those of two commercial breeds (Lohmann Selected Leghorn and ISA Brown) under two feeding regimes, either high (Hn-3) or low (Ln-3) in long-chain n-3 fatty acids. 2. The Hn-3 diet was formed by isocaloric substitution of animal fat in the control diet (Ln-3) by a dry product containing stabilised fish oil with standardised concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). 3. Both breed and diet had influences on egg composition, without interactions. 4. The Araucana breed showed lower feed intake and lower egg weights than the other two breeds. The yolk weight was similar, leading to a much higher yolk:albumen ratio in the Araucana eggs. 5. In comparison to commercial breeds, Araucanas produced eggs with higher cholesterol content per g of yolk, which was even more pronounced when expressed per g of egg, due to the high yolk content of the eggs. The cholesterol content of an egg remained unchanged by the diet, irrespective of the dietary fat source. 6. Changing to the Hn-3 diet led to greater concentrations of polyunsaturated fatty acids (PUFA) and lower concentrations of monounsaturated fatty acids (MUFA) contents in the yolk, without a change in the ratio of saturated (SFA) to unsaturated fatty acids (UFA). 7. Within the PUFA, the n-3 fatty acids increased at the expense of the n-6 fatty acids, indicating a competition between n-3 and n-6 fatty acids for incorporation in the yolk.     

混合油脂对清远麻鸡胸肌脂肪酸组成的影响及其代谢组机制研究

本试验旨在研究单一和混合油脂日粮对肉鸡生长性能和胸肌脂肪酸组成的影响，并利用代谢组学技术探究日粮油脂干预后胸肌脂肪酸组成发生变化的代谢机制，为调控肉鸡脂肪酸组成的研究提供新思路。选取1日龄慢速型清远麻母鸡480只，随机分为2组（每组6个重复，每个重复40只），对照组（CON）饲喂大豆油日粮，试验组（BOF）饲喂等量的混合油脂（大豆油∶猪油∶鱼油∶椰子油=1.0∶1.0∶0.5∶0.5）日粮，试验期127 d。结果表明，与对照组相比，混合油脂日粮对肉鸡平均日增重没有显著影响（P > 0.05），但显著降低了肉鸡的平均日采食量和料重比（P < 0.05）；显著增加了肉鸡胸肌中月桂酸（C12∶0）、肉豆蔻酸（C14∶0）、油酸（C18∶1n-9）、二十碳五烯酸（EPA，C20∶5n-3）和二十二碳六烯酸（DHA，C22∶6n-3）的比例，显著降低了亚油酸（C18∶2n-6）比例（P < 0.05）。利用液相色谱－质谱联用（LC-MS）技术，在试验鸡胸肌中共筛选到110种差异代谢物（变量权重值（VIP） > 1，P < 0.05），其中63种差异物质被注释，主要是磷脂代谢物，包括磷脂酰胆碱（PC）、磷脂酰丝氨酸（PS）和磷脂酰乙醇胺（PE）等。此外，与对照组相比，混合油脂组显著增加了胸肌中谷胱甘肽和肌肽含量（P < 0.05）。代谢通路富集分析表明，α-亚麻酸代谢、花生四烯酸代谢、亚油酸代谢和甘油磷酸代谢等脂质代谢通路发生显著改变（P < 0.05）。综上，混合油脂日粮相较于大豆油日粮提高了肉鸡的饲料转化效率，促进了胸肌组织中DHA和EPA的沉积；日粮油脂干预后肉鸡胸肌中磷脂代谢物、氧化稳定性代谢物和脂类代谢途径发生显著改变。本研究鉴定出的差异代谢物和差异代谢通路可为调控肉鸡脂肪酸组成的研究提供参考。