Velasco S, Cañeque V, Pérez C, Lauzurica S, Díaz M T, Huidobro F, Manzanares C, González J
Instituto Nacional de Investigación y Tecnologı́a Agraria y Alimentaria, Departamento de Tecnologı́a de los Alimentos, Carretera de la Coruña, km 7.5, 28040 Madrid, Spain.
Meat Sci. 2001 Nov;59(3):325-33. doi: 10.1016/s0309-1740(01)00135-8.
Forty-nine male Talaverana-breed suckling lambs slaughtered at 14 kg live weight were used to study the fatty acid composition of adipose depots of lambs raised under different management systems (pasture or drylot) and diets (maternal milk with or without a concentrate supplement). Drylot lambs displayed a higher fatness score, in addition to greater dorsal fat thickness; these parameters corresponded with a greater percentage of total fat at dissection. Addition of concentrate to the diet did not modify carcass fatness. Drylot lambs presented higher proportions of oleic acid (C18:1) and monounsaturated fatty acids (MUFA) and lower linolenic acid (C18:3) values in subcutaneous and intramuscular fat (muscle longissimus thoracis). The subcutaneous fat of these lambs thus displayed a higher n-6/n-3 PUFA ratio (C18:2/C18:3) than that of pasture-raised ones. Concentrate in the diet of both pasture and drylot lambs resulted in higher linoleic fatty acid (C18:2) and PUFA values and a greater PUFA/SFA ratio in intramuscular fat than the corresponding values of lambs which consumed maternal milk alone. Loin displayed a higher percentage of subcutaneous and intramuscular chemical fat than leg. Compared with intramuscular leg fat (muscle quadriceps femoris), intramuscular loin fat (muscle longissimus thoracis) had lower oleic acid (C18:1) and MUFA values, higher PUFA values and a higher PUFA/SFA ratio, due to greater linolenic acid (C18:3) levels.
选用49只体重达14千克时屠宰的塔拉韦拉品种雄性哺乳羔羊，研究不同饲养系统（牧场或舍饲）和日粮（有无精料补充的母乳）条件下饲养的羔羊脂肪组织的脂肪酸组成。舍饲羔羊除背部脂肪厚度更大外，还表现出更高的肥度评分；这些参数与屠宰时总脂肪的更高百分比相对应。日粮中添加精料并未改变胴体肥度。舍饲羔羊皮下和肌内脂肪（胸最长肌）中的油酸（C18:1）和单不饱和脂肪酸（MUFA）比例更高，亚麻酸（C18:3）值更低。因此，这些羔羊的皮下脂肪比牧场饲养的羔羊表现出更高的n-6/n-3多不饱和脂肪酸比例（C18:2/C18:3）。牧场和舍饲羔羊日粮中的精料均使肌内脂肪中的亚油酸（C18:2）和多不饱和脂肪酸值更高，且多不饱和脂肪酸/饱和脂肪酸比例比仅食用母乳的羔羊相应值更高。腰部的皮下和肌内化学脂肪百分比高于腿部。与股四头肌的肌内脂肪相比，胸最长肌的肌内腰部脂肪的油酸（C18:1）和MUFA值更低，多不饱和脂肪酸值更高，且多不饱和脂肪酸/饱和脂肪酸比例更高，这是由于亚麻酸（C18:3）水平更高。
