亚麻油对育肥猪肉品质及脂肪组织脂肪酸组成的影响

本试验旨在研究饲料添加亚麻油(linseed oil,LO)对育肥猪胴体指标、肉质及脂肪组织脂肪酸组成的影响.选用平均体质量为63 kg左右的健康大白猪84头(其中21头阉公猪),按体质量相近、性别比例一致原则随机分为3组,每组设4个重复,每个重复7头猪(1或2头阉公猪).3个处理口粮为玉米-豆粕型日粮,分别添加0%、1.5%和3.0%LO,饲养试验时间为50 d.结果显示,与对照组相比,日粮中添加LO对猪胴体和肉晶质指标均没有显著影响(P＞0.05);日粮中添加LO显著提高皮下脂肪的α-亚麻酸(ALA)(P＜0.01)、EPA(P＜0.01)、DPA(P＜0.05)含量,以及多不饱和脂肪酸(PUFA)(P＜0.05)和n-3PUFA(P＜0.01)总含量,同时显著降低花生四烯酸(P＜0.01)和二十二碳四烯酸(P＜0.01)含量,而对n-6PUFA总含量无显著影响(P＞0.05).结果表明,猪不但可以直接沉积α-亚麻酸,而且能将其进行进一步延长和脱饱和;饲料中添加1. 5% LO可将猪皮下脂肪n-6:n-3PUFA比值降至4.1:1,接近人类健康饮食推荐水平,而日粮中添加3.0%LO则能降低皮下脂肪n-6:n-3PUFA比值至2.5:1,大大增加了猪脂肪组织的保健价值.

Effects of Linseed Oil on Meat Quality and Fatty Acid Compositon of Adipose Tissue in Finishing Pigs

This experiment was conducted to study the effect of Linseed oil (LO) on meat quality and fatty acids composition of adipose tissue in finishing pigs. Eighty-four Large White pigs(21 barrows), average weight of 63 kg, were randomly assigned into three dietary treatments with four replicates and seven pigs (1 or 2 barrows)with each replicate. The groups received one of the three dietary treatments: 0%,1.5% and 3.0% LO, respectively. The feeding trial lasted for 50 days. There was no significant effect of LO added into diets on meat quality and carcass traits(P＞0. 05);The inclusion of LO in finishing pig diets significantly increased α-linolenic acid (ALA) (P＜0. 01), EPA(P＜0. 01) and DPA(P＜0. 05)levels,and total n-3 polyunsaturated fatty acid (PUFA) (P＜0. 01) concentration, and significantly reduced the levels of C20:4 n-6(P＜0. 01)and C22:4 n-6(P＜0. 01)in adipose tissue, but the total n-6 PUFA content was not significantly affected by the diet(P＞0. 05). These results indicated that pigs could not only deposit α-linolenic acid into adipose tissue, but also elongate and desaturate it; the 1.5 LO diet produced an n-6 : n-3PUFA ratio in the subcutaneous fat of 4. 1 : 1, close to the recommended ratio for the human diet, and the ratio of 2.5 : 1 for the 3.0% LO diet, which can significantly improve the health value of adipose tissue.