共轭亚油酸对鹌鹑蛋品质、蛋黄胆固醇及ω-3多不饱和脂肪酸含量的影响

Effects of Conjugated Linoleic Acid on Egg Quality, Cholesterol and ω-3 Polyunsaturated Fatty Acid Content in Egg Yolk of Laying Quail

试验旨在研究共轭亚油酸(CLA)添加对鹌鹑蛋品质、蛋黄胆固醇含量及ω-3多不饱和脂肪酸沉积的影响。选用15周龄"神丹1号"蛋鹌鹑400只,按单因子试验设计随机分成5组,每组4个重复,每个重复20只,各组日粮分别含0、0.75%、1.50%、2.25%和3.00%CLA,试验期42 d,分别收集第7、14、28和42天鹌鹑蛋进行分析。结果表明:日粮添加1.50%和2.25%CLA饲喂28 d后可显著降低鹌鹑蛋重(P<0.05),而添加3.00%CLA饲喂14 d后即显著降低鹌鹑蛋重(P<0.05)。CLA添加对蛋形指数、蛋壳厚度无显著影响(P>0.05)。日粮添加CLA饲喂至第7天,鹌鹑蛋黄中胆固醇含量随CLA添加浓度的增加而显著降低(P<0.05);饲喂14 d后,降低蛋黄胆固醇含量的最佳CLA添加量为1.50%。日粮添加CLA可降低鹌鹑蛋黄总ω-3多不饱和脂肪酸和二十二碳六烯酸(DHA)含量,小幅增加亚麻酸(ALA)和二十碳五烯酸(EPA)含量。综上所述,CLA添加浓度少于1.50%,饲喂时间少于14 d不影响鹌鹑蛋均重,但可显著降低蛋黄胆固醇含量,且对ω-3 PUFA沉积产生的不利影响较小。

The objective of this study was to investigate the effects of dietary conjugated linoleic acid （CLA）on egg quality, cholesterol and ω-polyunsaturated fatty acid content in egg yolk of quail. Four hundred 15-week-age ＂Shendan No.1＂ laying quails were randomly assigned to 5 dietary treatments with g replicates. Laying quails were fed corn and soybean meal-based diets containing 0, 0.75%, 1.50%, 2.25% or 3.00% CLA for 42 d. During the test period, eggs were collected to analysis on 7, 14, 28 and 42 d. The results showed that the average egg weight of 3.00% CLA group was significantly decreased after 14 d （P〈0.05）while 1.5% and 2.25% CLA groups were decreased after 28 d （P〈0.05）. The egg shape index and shell thickness were not influenced by CLA. The cholesterol contents of yolks were decreased with increasing dietary CLA at 7 d, but 1.5% CLA group had best effect on decreasing cholesterol level after 14 d （P〈0.05）. Increasing the amount of CLA would decrease the total ω-3 polyunsaturated fatty acids （PUFA） content of yolk. Specifically, DHA content was significantly decreased （P〈0.05）while EPA and ALA were increased a little. In conclusion, high level （〉1.50%）and long-term （more than 14 days）supplementation of CLA showed adverse effects on egg quality and DHA content of yolk.