An B K, Banno C, Xia Z S, Tanaka K, Ohtani S
Science of Biological Production, United Graduate School of Agricultural Science, Gifu University, Japan.
Comp Biochem Physiol B Biochem Mol Biol. 1997 Jan;116(1):119-25. doi: 10.1016/s0305-0491(96)00182-4.
The effect of dietary fat sources with different degrees of unsaturation and double bond positioning on lipid metabolism was studied in growing chicks. Four-week-old chicks were given semi-purified diets containing 6% palm oil (PLO), 6% safflower oil (SFO), 3% safflower oil and 3% linseed oil (SFO + LNO), 6% linseed oil (LNO), or 3% linseed oil and 3% fish oil (LNO + FO) with 0.5% cholesterol supplementation. Cholesterol ester content in the liver and serum of chicks fed PLO diet was significantly higher than that of other diet groups. Liver triacylglycerol and free cholesterol contents were significantly decreased in chicks fed a diet containing n-3 fatty acids (i.e., linseed oil or fish oil). Serum triacylglycerol level was also decreased by feeding the LNO or LNO + FO diet. The activity of serum lecithin-cholesterol acyltransferase was not affected by dietary treatments. Fecal neutral steroid excretion was significantly increased in the LNO+FO diet group as compared with the SFO + LNO or LNO diet groups. With the increase in linseed oil levels, the levels of C18:2n6 and C20:4n6 fatty acids in tissue lipids decreased, but C18:3n3 and C20:5n3 were gradually increased. The levels of longer chain n-3 fatty acids (i.e., C20:5n3 or C22:6n3) in chicks fed a diet containing fish oil (LNO + FO diet) were significantly increased compared to those fed linseed oil with a corresponding level. These results demonstrated that dietary fat enriched with alpha-linolenic acid and longer chain n-3 fatty acids have stronger effects on lowering serum lipid levels than dietary fat composed of either saturated, or n-6 fatty acids, but both n-3 fatty acids sources show differing effects on the deposition of longer chain n-3 fatty acids into tissue lipids.
研究了不同不饱和程度和双键位置的膳食脂肪来源对生长鸡脂质代谢的影响。给4周龄的雏鸡喂食半纯化日粮，日粮中含有6%的棕榈油（PLO）、6%的红花油（SFO）、3%的红花油和3%的亚麻籽油（SFO + LNO）、6%的亚麻籽油（LNO）或3%的亚麻籽油和3%的鱼油（LNO + FO），并添加0.5%的胆固醇。喂食PLO日粮的雏鸡肝脏和血清中的胆固醇酯含量显著高于其他日粮组。喂食含n-3脂肪酸（即亚麻籽油或鱼油）日粮的雏鸡肝脏三酰甘油和游离胆固醇含量显著降低。喂食LNO或LNO + FO日粮也可降低血清三酰甘油水平。日粮处理对血清卵磷脂胆固醇酰基转移酶的活性没有影响。与SFO + LNO或LNO日粮组相比，LNO+FO日粮组的粪便中性类固醇排泄显著增加。随着亚麻籽油水平的增加，组织脂质中C18:2n6和C20:4n6脂肪酸水平降低，但C18:3n3和C20:5n3逐渐增加。与喂食相应水平亚麻籽油的雏鸡相比，喂食含鱼油日粮（LNO + FO日粮）的雏鸡中长链n-3脂肪酸（即C20:5n3或C22:6n3）水平显著增加。这些结果表明，富含α-亚麻酸和长链n-3脂肪酸的膳食脂肪比由饱和脂肪酸或n-6脂肪酸组成的膳食脂肪对降低血清脂质水平的作用更强，但两种n-3脂肪酸来源对长链n-3脂肪酸在组织脂质中的沉积表现出不同的影响。
