| 摘要: |
| 为观察泌乳奶牛十二指肠灌注游离亚麻酸(LNA)对干物质采食量、养分表观消化率和乳成分的影响,选用4头安装有十二指肠和瘤胃瘘管的中国荷斯坦奶牛,用灌注游离α-亚麻酸(LNA)处理和空白对照交叉试验设计,每期试验持续5周;期间2头牛进行LNA增量灌注(0、30、60、90和120 g/d),每个剂量灌注1周,另外2头奶牛只灌注乳化载体。结果表明:灌注LNA对奶牛干物质采食量和养分表观消化率无显著影响(P＞0.05);随LNA灌注剂量的增加(0、30、60、90和120 g/d)乳产量趋于降低(18.54、17.17、16.94、15.93和16.28 kg/d(P=0.08));但4％ (质量分数)脂肪校正乳产量无降低趋势;乳脂肪含量随LNA灌注剂量的增加呈线性升高趋势(4.01、4.12、3.96、4.32和4.41 g/100g(P=0.09)),乳脂产量无变化;乳糖含量(4.56、4.60、4.68、4.59和4.57 g/100 g)和乳产量(0.85、0.79、0.79、0.73和0.74 kg/d)随LNA灌注量的增加呈现二次式降低(P＜0.05),乳蛋白含量和产量无变化。结果显示,增加泌乳奶牛小肠游离亚麻酸的供给量(＜120 g/d)对干物质采食量和养分消化率无不良影响;灌注LNA可降低乳糖含量和产量。 |
| 关键词: 奶牛 脂肪添加 α-亚麻酸 生产性能 乳成分 消化率 |
| DOI：10.11841/j.issn.1007-4333.2010.02.008 |
| 投稿时间：2009-07-02 |
| 基金项目:国家"十一五"科技支撑项目资助(2006BAD04A06)第一作者:哈斯额尔敦,博士研究生,E-mail:hsed-2002@hotmail.com通讯作者:王加启,研究员,博士生导师,主要从事反刍动物营养与牛奶品质改良研究,E-mail:wang-jia-qi@263.net |
|
| Effects of duodenal infusion of α-linolenic acid on nutrient digestionand production performance in dairy cows |
|
Khas-Erdene, WANG Jia-qi, BU Deng-pan, LIU Qing-sheng, YANG Guang, ZHOU Ling-yun, SUN Peng
|
| (State Key Laboratory of Animal Nutrition/Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, China) |
| Abstract: |
| The purpose of this study was to determine the effects of duodenal infusion of a high content of C18∶3 free fatty acid mixture on nutrient digestion, milk production, and milk composition in dairy cows. Four multiparous Chinese Holstein cows fitted with duodenal cannulas were administered with aqueous mixtures of α-linolenic acid (LNA; 82.4% cis-9, cis-12, cis-15 18∶3; 14.7% cis-9, cis-12 18∶2; 2.8% cis-9 18∶1) or only the emulsifying ingredients in a crossover design, each period lasted 5 wk. Two of these cows received continuous increased LNA (0, 30, 60, 90 and 120 g/d) for 1 wk for each amount, and the other 2 cows received only the carrier infusate. Measurements were made during the last 3 d of each infusion amount. The results showed that the dry matter intake and total tract apparent digestibilities of DM, OM, CP and ADF were not affected by LNA infusions. Milk production tended to decrease (18.54,17.17,16.94,15.9 and 16.28 kg/d for 0, 30, 60, 90 and 120 g/d infusion amount, respectively; P=0.08) as LNA infusion increased but production of 4% FCM was not changed. Milk fat content tended to increase linearly with LNA infusion (4.01,4.12,3.96,4.32 and 4.41 g/100g; P=0.09), however, milk fat yield was not changed. Milk protein content was not changed by LNA infusion, whereas milk lactose content (4.56,4.60,4.68,4.59 and 4.57 g/100 g)and milk lactose yield (0.85,0.79,0.79,0.73 and 0.74 kg/d)were quadratically affected with the increase of LNA infusion (P<0.05). The results indicated that increasing the amount of LNA supplied to the small intestine (＜120 g/d) of dairy cows had no effect on DMI and nutrient digestibility. Infusion of LNA did not affect milk protein or fat yield, but decreased milk lactose content and yield. |
| Key words: dairy cow fat supplement α-linolenic acid production performance milk composition digestibility |
