Department of Animal Science, Michigan State University, East Lansing, MI 48824.
Department of Animal Science, Michigan State University, East Lansing, MI 48824.
J Dairy Sci. 2023 Oct;106(10):6789-6797. doi: 10.3168/jds.2022-23143. Epub 2023 Jul 26.
We evaluated the effects of infusing an exogenous emulsifier (polysorbates-C18:1) either into the rumen or abomasum on fatty acid (FA) digestibility and production responses of lactating dairy cows. Nine ruminally cannulated multiparous Holstein cows (170 ± 13.6 d in milk) were assigned to a treatment sequence in replicated 3 × 3 Latin squares with 18-d periods consisting of 7 d of washout and 11 d of infusion. Treatments were abomasal infusions of water carrier only into the rumen and abomasum (control, CON), 30 g/d polysorbate-C18:1 (T80) infused into the rumen (RUM), or 30 g/d T80 infused into the abomasum (ABO). Emulsifiers were dissolved in water and delivered at 6-h intervals (total daily infusion was divided into 4 equal infusions per day). Cows were fed the same diet that contained [% diet dry matter (DM)] 32.2% neutral detergent fiber (NDF), 16.1% crude protein, 26.5% starch, and 3.41% FA (including 1.96% FA from a saturated FA supplement containing 28.0% C16:0 and 54.6% C18:0). Two orthogonal contrasts were evaluated: (1) the overall effect of T80 {CON vs. average of the T80 infusions [1/2 (ABO + RUM)]}, and (2) the effect of ABO versus RUM infusion. Compared with CON, infusing T80 increased the digestibilities of NDF (2.85 percentage units), total (4.35 percentage units), 16-carbon (3.25 percentage units), and 18-carbon FA (4.60 percentage units), and tended to increase DM digestibility and total and 18-carbon FA absorption. Compared with RUM, ABO decreased the intakes of total (28 g/d), 16-carbon (7 g/d), and 18-carbon FA (19 g/d); tended to increase the digestibility of total and 18-carbon FA; and had no effect on the absorption of total, 16-carbon, or 18-carbon FA. Production responses did not change among our treatments. In conclusion, infusing 30 g/d polysorbates-C18:1 increased NDF and total, 16-carbon, and 18-carbon FA digestibility. Compared with RUM, ABO tended to increase the digestibilities of total and 18-carbon FA; however, this may be related to the fact that ABO reduced the intakes of total, 16-carbon, and 18-carbon FA, not necessarily due to better emulsifying action per se. In summary, ABO and RUM both improved FA absorption.
我们评估了向瘤胃或皱胃中输注外源性乳化剂（聚山梨醇酯-C18:1）对泌乳奶牛脂肪酸（FA）消化率和生产性能的影响。9 头瘤胃内置有套管的经产荷斯坦奶牛（泌乳 170±13.6 天）按处理顺序分配到复制的 3×3 拉丁方试验中，每个试验期 18 天，包括 7 天的清洗期和 11 天的输注期。处理措施为仅向瘤胃和皱胃中输注水载体（对照，CON）、向瘤胃中输注 30 g/d 聚山梨醇酯-C18:1（RUM）或向皱胃中输注 30 g/d T80（ABO）。乳化剂溶于水中，每 6 小时输注一次（每日总输注量分为 4 等份）。奶牛饲喂相同的日粮，日粮干物质（DM）中含有[ %]32.2%中性洗涤纤维（NDF）、16.1%粗蛋白、26.5%淀粉和 3.41% FA（包括 1.96%来自含有 28.0% C16:0 和 54.6% C18:0 的饱和 FA 补充剂的 FA）。评估了两个正交对比：（1）T80 的总体影响{CON 与 T80 输注的平均值[1/2（ABO + RUM）] }，和（2）ABO 与 RUM 输注的影响。与 CON 相比，输注 T80 增加了 NDF（2.85 个百分点）、总 FA（4.35 个百分点）、16-碳 FA（3.25 个百分点）和 18-碳 FA（4.60 个百分点）的消化率，并且趋于增加 DM 消化率和总 FA 和 18-碳 FA 的吸收。与 RUM 相比，ABO 减少了总 FA（28 g/d）、16-碳 FA（7 g/d）和 18-碳 FA（19 g/d）的摄入量；趋于增加总 FA 和 18-碳 FA 的消化率；并且对总 FA、16-碳 FA 或 18-碳 FA 的吸收没有影响。我们的处理措施没有改变生产反应。总之，每天输注 30 g/d 聚山梨醇酯-C18:1 增加了 NDF 和总 FA、16-碳和 18-碳 FA 的消化率。与 RUM 相比，ABO 趋于增加总 FA 和 18-碳 FA 的消化率；然而，这可能与 ABO 减少了总 FA、16-碳 FA 和 18-碳 FA 的摄入量有关，而不一定是由于本身更好的乳化作用。总之，ABO 和 RUM 都提高了 FA 的吸收。
