Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan, 84156 - 83111, Iran.
Trop Anim Health Prod. 2022 Sep 8;54(5):284. doi: 10.1007/s11250-022-03296-3.
The present study determined the effect of supplementing palmitic acid (PA) and stearic acid (SA) on the nutrient intake, digestibility, and serum metabolites of dairy cows fed two different starch levels during the postpartum period. Forty-four multiparous Holstein cows were used in a completed randomized block based on their parity and previous milk yield. Dietary treatments were arranged in a 2 × 2 arrangement with two dietary starch levels (HS: 260 g/kg of diet dry matter (DM) vs LS: 210 g/kg of diet DM) and two fat supplements rich in PA or SA at 15 g/kg of diet DM. Increasing the starch concentration of the postpartum diet improved organic matter (OM), ether extract (EE), crude protein (CP), and starch intake. Moreover, HS diets resulted in higher apparent digestibility of OM and CP but lower starch digestibility than LS diets. Feeding HS diets increased fecal starch output compared with LS diets. There was starch levels and FA supplements interaction for serum albumin and total antioxidant capacity (TAC), with higher concentrations in HSSA and LSPA compared to HSPA and LSSA. Significant correlations between performance and blood metabolites were observed in weeks 3 and 4. In week 3, a negative correlation was observed between serum TAC with milk protein (r = - 0.51) and lactose percentage (r = - 0.49) in the HS diet. However, non-esterified FA was correlated with the fat to protein ratio in the LS diet (r = 0.54). Moreover, in week 4, serum TAC was negatively related to the body condition score of the cows fed LS diet (r = 0.50), while there was no relationship for cows fed HS diets. In conclusion, feeding HS diets to postpartum cows increased nutrient intake and the digestibility of OM and CP compared with LS diets. The addition of SA to the HS diet may be more beneficial than PA in improving the oxidative status of dairy cows in the postpartum period.
本研究旨在确定在产后阶段给奶牛饲喂两种不同淀粉水平日粮时补充棕榈酸（PA）和硬脂酸（SA）对营养物质摄入、消化率和血清代谢物的影响。根据胎次和前次产奶量，将 44 头经产荷斯坦奶牛采用完全随机区组设计分为 4 个区组。日粮处理采用 2×2 完全随机设计，两个日粮淀粉水平（HS：260g/kg 日粮干物质（DM）与 LS：210g/kg 日粮 DM）和两种富含 PA 或 SA 的脂肪补充剂（15g/kg 日粮 DM）。增加产后日粮淀粉浓度可提高干物质（OM）、乙醚提取物（EE）、粗蛋白（CP）和淀粉采食量。此外，HS 日粮导致 OM 和 CP 的表观消化率升高，但淀粉消化率降低。与 LS 日粮相比，HS 日粮增加了粪便淀粉的排出量。血清白蛋白和总抗氧化能力（TAC）存在淀粉水平和 FA 补充剂的互作，HSSA 和 LSPA 中浓度高于 HSPA 和 LSSA。在第 3 周和第 4 周观察到性能和血液代谢物之间存在显著相关性。在第 3 周，HS 日粮中血清 TAC 与乳蛋白（r = -0.51）和乳糖百分比（r = -0.49）呈负相关。然而，非酯化 FA 与 LS 日粮中的脂肪与蛋白质比例呈正相关（r = 0.54）。此外，在第 4 周，LS 日粮饲喂的奶牛血清 TAC 与体况评分呈负相关（r = 0.50），而 HS 日粮饲喂的奶牛则没有相关性。总之，与 LS 日粮相比，给产后奶牛饲喂 HS 日粮可增加营养物质摄入和 OM 和 CP 的消化率。在产后阶段，与 PA 相比，给 HS 日粮添加 SA 可能更有利于提高奶牛的氧化状态。
