Department of Agricultural Sciences, Biotechnology and Food Sciences, Cyprus University of Technology, P.O. Box 50329, Lemesos, Cyprus.
Trop Anim Health Prod. 2021 Mar 26;53(2):229. doi: 10.1007/s11250-021-02674-7.
This study aimed to evaluate the use of a by-product, olive cake silage (OCS), as a forage replacement in sheep diets for the improvement of fatty acid (FA) content of milk and thus, the lipids of the ovine halloumi cheese produced. Sixty second-parity purebred Chios ewes in mid-lactation were assigned to three diet treatments (2 lots of 10 animals per treatment) receiving 0%, 10%, and 20% of OCS on dry matter basis for 3 weeks (treatments S0, S10, and S20, respectively). Halloumi cheese was manufactured from fresh raw milk of ewes fed the three different diets. Inclusion of OCS in the diets increased linearly the concentration in milk of unsaturated FA up to 20%, monounsaturated FA up to 23%, polyunsaturated FA up to 11%, rumenic acid (CLA cis-9, trans-11) up to 61%, and consequently reduced the atherogenicity and thrombogenicity milk indices by 31% and 27%, for the S10 and S20 treatments, respectively, compared with the control treatment. Moreover, these differences were carried over to the lipid profile of ovine halloumi cheese showing, on average, more than 25% increase of unsaturated, polyunsaturated, and monounsaturated FA, with particularly enhanced oleic and rumenic acid content. These changes resulted in reduced atherogenicity by 29% and 45% and thrombogenicity by 23% and 24% of ovine halloumi cheese made from milk of S10 and S20 diets, respectively. Milk yield, milk fat, or protein content was not affected by S10 or S20 feeding treatments compared to control. Overall, the applied ensiling method of olive cake produces a by-product that can be included as a forage replacement up to 20% of DM intake in Chios sheep without adversely affecting the lactating performance. Furthermore, the present study showed that such substitution improves the lipid quality of milk and related halloumi cheese enriching these ovine dairy products with beneficial to human health fatty acids.
本研究旨在评估橄榄饼青贮（OCS）作为绵羊饲料中替代物的用途，以改善牛奶中的脂肪酸（FA）含量，从而提高所产羊乳干酪的脂质含量。60 只处于泌乳中期的纯血奇奥绵羊被分配到 3 种饮食处理组（每组 10 只），分别接受干物质基础上 0%、10%和 20%的 OCS，为期 3 周（处理组 S0、S10 和 S20）。从饲喂三种不同日粮的母羊的新鲜原料乳中生产羊乳干酪。在日粮中添加 OCS 可使牛奶中不饱和 FA 的浓度线性增加至 20%，单不饱和 FA 增加至 23%，多不饱和 FA 增加至 11%，瘤胃酸（CLA 顺式-9，反式-11）增加至 61%，并分别使 S10 和 S20 处理组的致动脉粥样硬化和血栓形成的牛奶指数降低 31%和 27%，与对照组相比。此外，这些差异还延续到绵羊乳干酪的脂质谱中，平均显示出超过 25%的不饱和、多不饱和和单不饱和 FA 的增加，特别是油酸和瘤胃酸含量增加。这些变化使 S10 和 S20 日粮奶制成的羊乳干酪的致动脉粥样硬化性降低了 29%和 45%，血栓形成性降低了 23%和 24%。与对照组相比，S10 或 S20 饲养处理对牛奶产量、乳脂或蛋白质含量没有影响。总体而言，橄榄饼的应用青贮方法产生的副产品可以作为 Chios 绵羊饲料中 DM 摄入量的 20%的替代物，而不会对泌乳性能产生不利影响。此外，本研究表明，这种替代物可以改善牛奶的脂质质量，并使相关的羊乳干酪富含对人体健康有益的脂肪酸，从而丰富这些绵羊乳制品。
