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。     

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。     

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.     

亚麻籽和鱼油对蛋鸡蛋黄n-3多不饱和脂肪酸含量与肝脏脂肪酸代谢的影响

本试验旨在研究饲粮中添加亚麻籽和鱼油对蛋鸡蛋黄n-3多不饱和脂肪酸含量、肝脏脂肪酸组成及其合成代谢基因表达的影响。选择28周龄海兰褐壳蛋鸡96只,随机分为4组,每组24只。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加10%亚麻籽、10%亚麻籽+5%鱼油和5%鱼油。饲养21 d后连续收集7 d鸡蛋,然后每组随机选取4只鸡屠宰取样。结果表明,与对照组相比:1)添加亚麻籽和鱼油均显著增加蛋黄中n-3多不饱和脂肪酸含量(P0.05),其中单独添加鱼油的蛋黄中二十二碳六烯酸(DHA)和二十碳五烯酸含量最高;2)试验组肝脏单不饱和脂肪酸比例均显著降低(P0.05),肝脏n-3多不饱和脂肪酸比例均显著增加(P0.05);3)单独添加鱼油显著降低肝脏脂肪酸延长酶1、脂肪酸延长酶2和去饱和酶(脂肪酸去饱和酶1、脂肪酸去饱和酶2和硬脂酰辅酶A去饱和酶1)基因表达水平(P0.05)。由此可见,蛋鸡饲粮中单独添加亚麻籽或鱼油可以富集蛋黄n-3多不饱和脂肪酸沉积;添加亚麻籽促进肝脏α-亚麻酸转化生成DHA过程,表现为上调脂肪酸延长酶和去饱和酶基因表达,添加鱼油显示相反结果。     

Hypocholesterolemic effect of karaya saponin in Japanese laying quails (Coturnix coturnix japonica)

The effect of karaya saponin supplementation on the serum and egg yolk cholesterol and fatty acid composition in egg yolk were investigated in Japanese quails. A total of 80 Japanese quails aged 5 weeks were equally divided into four groups of 20. Four levels (0, 25, 50 and 75 mg/kg feed) of karaya saponin were included in the basal diet and experiment was lasted for 6 weeks. The cholesterol fractions in the egg yolk and serum were measured by enzymatic assay, and the fatty acid composition in egg yolk was determined by gas chromatography. The results revealed that the supplementation of 75 mg/kg karaya saponin significantly reduced (p < 0.05) cholesterol and triglycerides concentration in serum and egg yolk. High-density lipoprotein-cholesterol was increased, low-density lipoprotein-cholesterol and the atherogenic index were decreased (p < 0.05) by the dietary supplementations. Hepatic cholesterol was reduced (p < 0.05) by the 25 mg/kg karaya saponin. A higher degree of yolk colour was improved (p < 0.05) when 75 mg/kg saponin was supplemented in the diet. The concentration of polyunsaturated fatty acids (PUFA) in egg yolk was increased (p < 0.05) in a dose-dependent manner in quails fed the supplemented diet than the control diet. The ratio of PUFA to saturated fatty acids in egg yolk was improved (p < 0.05) by 75 mg/kg feed karaya saponin-supplemented diet. Therefore, the dietary supplementation of 75 mg/kg karaya saponin may be a feasible means of producing quail eggs with lower cholesterol and higher PUFA content for health conscious consumers.     

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.     

Effect of dietary omega-3 fatty acids on red blood cell lipid composition and plasma metabolites in the cockatiel, Nymphicus hollandicus

Although dietary n-3 fatty acids have been extensively studied in poultry, they have not yet been prospectively investigated in psittacines, despite potential benefits for preventing and treating atherosclerosis, osteoarthritis, and other chronic disease processes. The objectives of this study were to investigate the incorporation of dietary n-3 fatty acids into red blood cells (RBC) and to determine the effects of supplementation of psittacine diets with fish or flax oil on plasma lipids and lipoproteins in the cockatiel. Adult cockatiels were fed a custom-formulated diet containing either 4% (wt/wt, as-fed) beef tallow (CON), 3% fish oil + 1% tallow (FSH), or 3.5% flax oil + 0.5% tallow (FLX; n = 20 per diet group). Baseline measurements were obtained for RBC fatty acid composition, triacylglycerides (TAG), and cholesterol. After 8 to 13 wk on the study diets, plasma chemistry profiles, lipoprotein density profiles, and RBC fatty acid composition were determined. At 8 wk, total plasma cholesterol was least in FSH birds (P < 0.05) and TAG concentrations were less in FSH birds than FLX birds (P < 0.05). Total n-3 fatty acids, docosahexaenoic acid, docosapentaenoic acid, and eicosapentaenoic acid were markedly greater in the RBC of FSH birds than FLX or CON birds (P < 0.05). Alpha linolenic acid was greatest in FLX (P < 0.05). Initial and final BW, and nonlipid plasma chemistry values did not differ among diet groups. No adverse effects of dietary supplementation of cockatiels with 3.5% flax oil or 3% fish oil were observed during the 13-wk feeding period. Although fish and flax oils provided similar total n-3 PUFA to the diets, fish oil caused greater reductions in cholesterol and TAG, and greater total RBC n-3 incorporation. Thus, dietary modification of psittacine diets with long chain n-3 PUFA from fish oil appears safe and may be beneficial to these long-lived companion birds.     

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。     

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.     

日粮中添加辣诺素对海兰褐蛋鸡产蛋性能和蛋品质的影响

本试验旨在研究日粮中添加辣诺素（辣木和诺丽果的提取物）对蛋鸡生产性能及蛋品质的影响。将产蛋高峰期（22周龄）的海兰褐商品蛋鸡540只随机分为6个处理,每个处理6个重复,每个重复15只鸡。负对照组（NC）饲喂基础日粮,正对照组（PC）饲喂添加50 mg/kg杆菌肽锌的基础日粮,4个试验组分别饲喂添加0.25、0.50、0.75和1.00 g/kg辣诺素（LNS）的基础日粮。试验期24周。结果显示：①日粮处理对蛋鸡试验前期和后期生产性能均无显著影响（P>0.05）,试验后期添加0.50和0.75 g/kg辣诺素有改善料蛋比的趋势（P=0.087）;日粮处理对试验前期和后期鸡蛋蛋形指数、蛋壳强度、蛋壳厚度、蛋黄重和哈氏单位均无显著影响（P>0.05）,但日粮中添加杆菌肽锌和辣诺素有提高蛋壳强度的趋势（P=0.062）,其中以添加0.75g/kg辣诺素组鸡蛋强度最高。②与正、负对照组相比,添加辣诺素显著增加了生蛋黄和熟蛋黄的罗氏蛋黄色比率（P<0.05）,显著降低了蛋黄胆固醇的含量（0.25 LNS组除外）（P<0.05）。③与负对照组相比,添加0.50 g/kg辣诺素显著提高了鸡蛋总黄酮、二十二碳六烯酸（DHA）、卵磷脂、亚麻酸和亚油酸含量（P<0.05）。综合以上试验结果,辣诺素作为饲料添加剂具有提高鸡蛋营养品质的功能,考虑到添加成本,产蛋鸡日粮中添加0.25~0.50 g/kg为宜。     

油脂对鸡蛋内容物含量影响的研究

为探讨不同油脂对蛋鸡生产性能及蛋黄多不饱和脂肪酸和胆固醇含量的影响,160只42周龄的海塞克斯蛋鸡随机分成四组,分别饲喂对照日粮、5%鱼油、5%棕榈油和5%豆油日粮,试验三周。结果表明,棕榈油组的产蛋量比豆油组高(P<0.05),而对照组的平均蛋重和蛋黄重明显低于鱼油组(P<0.05),鱼油组鸡的总增重明显高于豆油组(P<0.05);鱼油组的血清和蛋黄的胆固醇含量都低于棕榈油和对照组(P<0.01);鱼油组蛋黄中的C20:5n-3含量明显高于对照组和豆油组(P<0.01),鱼油组蛋黄中的C22:6n-3含量高于棕榈油组(P<0.01);豆油组的C18:1n-9含量最低,与棕榈油组的相比,差异显著(P<0.05);豆油组的C18:2n-6含量明显高于其它三组(P<0.01),又以对照组最低,与鱼油组相比,差异显著(P<0.05);鱼油组的C18:3n-3含量高于豆油组和棕榈油组(P<0.05);鱼油组的C20:1n-9含量明显高于其它三组(P<0.01)。     

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。     

桑叶粉对蛋鸡生产性能及蛋品质的影响研究

选用240只330日龄的健康罗曼商品蛋鸡,随机分为5个组,每组3个重复,每个重复16只。5组蛋鸡饲喂5种日粮,对照组饲喂基础日粮,其他处理组在基础日粮的基础上分别添加2%、4%、6%和8%的桑叶粉形成的试验日粮,试验期5周,研究桑叶粉对蛋鸡生产性能和蛋品质的影响。试验结果表明：在蛋鸡日粮中添加桑叶粉能降低蛋鸡每日的采食...     

Effect of dietary Rhodobacter capsulatus on lipid fractions and egg-yolk fatty acid composition in laying hens

The present study was conducted to investigate the effect of dietary Rhodobacter capsulatus on lipid fractions and egg‐yolk fatty acid composition in laying hens. Thirty‐six laying hens (30 weeks old) were randomly assigned into two dietary groups fed diets with (0.04%) or without (control) R. capsulatus for a 60‐day feeding trial. Dietary R. capsulatus decreased (p < 0.05) serum and hepatic cholesterol and increased (p < 0.05) the excreta cholesterol, and resultant lower (p < 0.05) cholesterol contents in egg yolk. The concentration of polyunsaturated fatty acids (PUFA) and ratio to saturated fatty acids in egg yolk was improved (p < 0.05) by dietary R. capsulatus. The concentration of hepatic bile acid was increased (p < 0.05) and excreta bile acid was decreased (p < 0.01) in the laying hens fed R. capsulatus diet. The incorporation of 1‐¹⁴C‐palmitic acid into hepatic lipids and lipid fractions was increased (p < 0.05) in laying hens fed R. capsulatus diet. Moreover, dietary R. capsulatus did not appear to cause any adverse effects on laying hen performances. Therefore, dietary supplementation of R. capsulatus in layer diets may be a feasible means of producing eggs with lower cholesterol and higher PUFA contents for health conscious consumers.     

鲜茶叶粉对蛋鸡生产性能、蛋品质、蛋黄脂肪酸水平及经济指标的影响

文章旨在评估日粮添加不同水平的鲜茶叶粉对蛋鸡生产性能、蛋品质及蛋黄脂肪酸水平的影响。试验将672只产蛋性能一致的28周龄海兰褐壳蛋鸡随机分为4组,每组4个重复,每个重复42只。对照组饲喂基础日粮,处理组蛋鸡分别饲喂基础日粮+20（T1）、40（T2）和60?mg/kg（T3）鲜茶叶粉,试验为期6周。结果：与对照组相比,T3组蛋鸡蛋重显著提高6.12%（P＜0.05）。T3和T2组蛋鸡料蛋比较对照组和T1分别显著降低了4.07、6.67%和2.12%、4.77%。T2和T3组蛋壳厚度较对照组分别显著提高了2.06%和2.27%（P＜0.05）。此外,T3组蛋黄颜色a值较对照组和T1组分别显著提高了34.78%和20.16%（P＜0.05）。T3组蛋黄胆固醇含量分别较其他组显著降低了10.90%、7.23%和8.16%（P＜0.05）,而对照组蛋黄硫代巴比妥酸值较处理组分别显著提高了54.91%、59.52%和57.65%（P＜0.05）,而T3组蛋黄C16：1脂肪酸水平较对照组和其他组分别显著降低25.60%、20.05%和24.51%（P＜0.05）。结论：日粮添加60?mg/kg鲜茶叶粉可以显著提高蛋鸡的蛋重、饲料效率和蛋壳厚度,降低蛋黄胆固醇及硫代巴比妥酸值。 [关键词]鲜茶叶粉|蛋鸡|生产性能|蛋品质|脂肪酸     

Effect of dietary α‐tocopherol on the bioavailability of lutein in laying hen

Lutein and its isomer zeaxanthin have gained considerable interest as possible nutritional ingredient in the prevention of age‐related macular degeneration (AMD) in humans. Egg yolk is a rich source of these carotenoids. As an oxidative sensitive component, antioxidants such as α‐tocopherol (T) might contribute to an improved accumulation in egg yolk. To test this, chickens were fed lutein esters (LE) with and without α‐tocopherol as an antioxidant. After depletion on a wheat–soya bean‐based lutein‐poor diet for 21 days, laying hens (n = 42) were equally divided into three groups and fed the following diets for 21 days: control (basal diet), a LE group (40 mg LE/kg feed) and LE + T group (40 mg LE plus 100 mg T/kg feed). Eggs and blood were collected periodically. Carotenoids and α‐tocopherol in yolk and blood plasma were determined by HPLC. Egg yolk was also analysed for total carotenoids using a one‐step spectrophotometric method (iCheck^(?)). Lutein, zeaxanthin, α‐tocopherol and total carotenoids in egg yolk were highest after 14 days of feeding and decreased slightly afterwards. At the end of the trial, eggs of LE + T group contained higher amount of lutein (13.72), zeaxanthin (0.65), α‐tocopherol (297.40) and total carotenoids (21.6) compared to the LE group (10.96, 0.55, 205.20 and 18.0 mg/kg, respectively, p < 0.05). Blood plasma values of LE + T group contain higher lutein (1.3), zeaxanthin (0.06) and tocopherol (20.1) compared to LE group (1.02, 0.04 and 14.90 mg/l, respectively, p < 0.05). In conclusion, dietary α‐tocopherol enhances bioavailability of lutein reflecting higher content in egg yolk and blood plasma. Improved bioavailability might be due to increased absorption of lutein in the presence of tocopherol and/or a greater stability of lutein/zeaxanthin due to the presence of α‐tocopherol as an antioxidant.     

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.     

叶黄素对蛋鸡应用效果的研究

将144只52周龄绿壳商品产蛋鸡随机分为6组,各组在相同日粮基础上分别添加0、20、40、60、80、100mg/kg叶黄素,探讨叶黄素在蛋黄中的沉积规律以及对蛋黄色泽和蛋鸡生产性能的影响。结果说明,蛋黄中叶黄素的含量随日粮中叶黄素添加水平的增加而提高,最大沉积量达1.09mg/60g,是对照组0.23mg/60g的近5倍;日粮中叶黄素能显著(P<0.05)提高蛋黄的罗氏等级(RCF),降低亮值(L),提高红值(a),对黄值(b)无显著影响(P>0.05);日粮中添加高水平叶黄素对蛋鸡生产性能无显著影响(P>0.05)。     

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.     

Egg quality and lipid composition of eggs from hens fed Camelina sativa

The present study was conducted to investigate the effect of feeding Camelina sativa to layer birds on egg production, egg quality characteristics, egg lipids, and fatty acid and lipid oxidation products. Fifty-eight-week-old ISA Brown Leghorn laying hens (n = 48) were kept in individual cages and were fed a corn- and soybean meal-based diet with added Camelina meal at 0%, (control), 5%, (CAM5), 10% (CAM10), and 15% (CAM15). The experimental diets were fed for a period of 80 d. Hen-day egg production was lowest for CAM15 (P < 0.05). A significant reduction in yolk weight was observed for CAM10 and CAM15 eggs when compared with control eggs (P < 0.05). Yolk weight, as a percentage of egg weight, was lower for CAM10 and CAM15 eggs, whereas albumen weight, as a percentage of egg weight, was higher in CAM10 and CAM15 eggs than in control eggs (P < 0.05). The yolk:albumen ratio was higher in control eggs than in CAM10 and CAM15 eggs (P < 0.05). Egg total fat content was lowest for CAM15 eggs and was 31.5, 31.9, 30.8, and 29.5 for control, CAM5, CAM10, and CAM15 eggs, respectively (P < 0.05). Total n-3 fatty acids constituted 0.32% in control eggs compared with 2.54, 2.69, and 2.99% in CAM5, CAM10, and CAM15 eggs (P < 0.05). An 8-fold increase in docosahexaenoic acid was observed in CAM15 eggs when compared with control eggs (P < 0.05). The n-6:n-3 ratio was 14.8, 5.6, 4.6, and 4.3 for control, CAM5, CAM10, and CAM15 eggs, respectively (P < 0.05). Total saturated fats were lowest for CAM5 and CAM10 eggs. Eggs from the CAM15 regimen had higher TBA-reactive substance values (P < 0.05) than those from the CAM5, CAM10, or control regimen. Camelina meal could be incorporated into poultry rations as a source of energy, protein, and essential n-3 and n-6 fatty acids. However, inclusion of more than 10% Camelina meal in the hen diet may affect egg lipid quality aspects. Therefore, measures for minimizing lipid peroxidation should be used to enhance egg quality and lipid stability.