日糧油脂對高產母豬奶水組成及必須脂肪酸平衡的影響

2017-7-5 09:11| 發布者: 畜牧編輯| 查看: 1438| 評論: 1|原作者: 畜牧編輯

　　2015. J. Anim. Sci. 93(6): 2935-2947

　　D. S. Rosero, J. Odle, S. M. Mendoza, R. D. Boyd, V. Fellner和E. van Heugten

　　本論文開展兩個試驗研究日糧中添加油脂（必需脂肪酸亞油酸和α-亞麻酸的日糧來源）對高產母豬奶水組成的影響，并預估母豬必需脂肪酸的沉積。

　　試驗一，30頭母豬，處理間母豬胎次一致，每頭母豬帶仔12頭。試驗處理為6%動植物混合油（A-V），6%精煉油（CWG）和對照組（無油脂添加）。日糧為玉米豆粕型，并添加8%玉米DDGS、6%麥麩，日糧中SID賴氨酸含量為3.25g /Mcal代謝能。日糧中添加油脂可以增加母豬奶水中脂肪的分泌量（P=0.082，559g/d VS 499g/d）。必需脂肪酸沉積以表觀回腸吸收量減去乳中分泌量計算得到。對照組哺乳母豬奶水中的亞油酸分泌量高于攝入量，導致了哺乳母豬機體亞油酸的負平衡（分娩后第3、10、17天分別為-22.4、-38.0、-14.1g/d）。

　　試驗二，50頭母豬，處理間胎次一致，每頭母豬帶仔12頭。將母豬隨機分為五組，一組為對照組（無脂肪添加），另四組為2×2雙因素試驗設計，試驗處理包括兩個亞油酸水平（添加量分別為2.1%和3.3%）和兩個α-亞麻酸水平（添加量為0.15%和0.45%）。試驗處理由日糧中添加4%不同比例的混合油脂（菜籽油、玉米油、亞麻油）達成。日糧中n-6和n-3脂肪酸比例由5至22不等。增加日糧中必須脂肪酸含量可以提高乳汁中亞油酸（P < 0.001；日糧中亞油酸2.1%和3.3%添加量組乳中亞油酸含量分別為16.7%和20.8%）和α-亞麻酸的含量（P < 0.001；日糧中α-亞麻酸0.15%和0.45%組乳中α-亞麻酸分別為1.1%和1.9%）。日糧中添加必需脂肪酸可以增加α-亞麻酸的沉積（P＜0.001；0.15%和0.45%組分別為-0.2和5.3g/d），但是對亞油酸沉積無顯著影響（P=0.14；2.1%和3.3%添加量組分別為-3.4和10.0g/d）。總之，哺乳母豬日糧中添加脂肪能增加乳脂分泌。日糧中必需脂肪酸的添加可以改變乳脂脂肪酸組成。日糧中添加必須脂肪酸可以促進哺乳母豬必需脂肪酸的儲備，隨后改善保育豬的健康和母豬后期生產水平。

　　Impact of dietary lipids on sow milk composition and balance of essential fatty acids during lactation in prolific sows

　　D. S. Rosero, J. Odle, S. M. Mendoza, R. D. Boyd, V. Fellner and E. van Heugten

　　Two studies were designed to determine the effects of supplementing diets with lipid sources of EFA (linoleic and α-linolenic acid) on sow milk composition to estimate the balance of EFA for sows nursing large litters. In Exp. 1, 30 sows, equally balanced by parity (1 and 3 to 5) and nursing 12 pigs, were fed diets supplemented with 6% animal-vegetable blend (A-V), 6% choice white grease (CWG), or a control diet without added lipid. Diets were corn-soybean meal based with 8% corn distiller dried grains with solubles and 6% wheat middlings and contained 3.25 g standardized ileal digestible Lys/Mcal ME. Sows fed lipid-supplemented diets secreted greater amounts of fat (P = 0.082; 499 and 559 g/d for control and lipid-added diets, respectively) than sows fed the control diet. The balance of EFA was computed as apparent ileal digestible intake of EFA minus the outflow of EFA in milk. For sows fed the control diet, the amount of linoleic acid secreted in milk was greater than the amount consumed, throughout lactation. This resulted in a pronounced negative balance of linoleic acid (-22.4, -38.0, and -14.1 g/d for d 3, 10, and 17 of lactation, respectively). In Exp. 2, 50 sows, equally balanced by parity and nursing 12 pigs, were randomly assigned to a 2 × 2 factorial arrangement of diets plus a control diet without added lipids. Factors included linoleic acid (2.1% and 3.3%) and α-linolenic acid (0.15% and 0.45%). The different concentrations of EFA were obtained by adding 4% of different mixtures of canola, corn, and flaxseed oils to diets. The n-6 to n-3 fatty acid ratios in the diets ranged from 5 to 22. Increasing supplemental EFA increased (P < 0.001) milk concentrations of linoleic (16.7% and 20.8%, for 2.1% and 3.3% linoleic acid, respectively) and α-linolenic acid (P < 0.001; 1.1 and 1.9% for 0.15 and 0.45% α-linolenic acid, respectively). Increasing supplemental EFA increased the estimated balance of α-linolenic acid (P < 0.001; -0.2 and 5.3 g/d for 0.15% and 0.45% α-linolenic acid, respectively), but not linoleic acid (P = 0.14; -3.4 and 10.0 g/d for 2.1% and 3.3% linoleic acid, respectively). In conclusion, lipid supplementation to sow lactation diets improved milk fat secretion. The fatty acid composition of milk fat reflected the dietary supplementation of EFA. The net effect of supplemental EFA was to create a positive balance during lactation, which may prove to be beneficial for the development of nursing piglets and the subsequent reproduction of sows.