补充糖蜜对以苜蓿和玉米青贮为基础日粮的泌乳奶牛生产性能的影响。

Effect of molasses supplementation on the production of lactating dairy cows fed diets based on alfalfa and corn silage.

作者信息

Broderick G A, Radloff W J

机构信息

Agricultural Research Service, USDA US Dairy Forage Research Center, 1925 Linden Drive West, Madison, WI 53706, USA.

出版信息

J Dairy Sci. 2004 Sep;87(9):2997-3009. doi: 10.3168/jds.S0022-0302(04)73431-1.

DOI:10.3168/jds.S0022-0302(04)73431-1

PMID:15375061

Abstract

Adding sugar to the diet has been reported to improve production in dairy cows. In each of 2 trials, 48 lactating Holsteins (8 with ruminal cannulas) were fed covariate diets for 2 wk, blocked by days in milk into 12 groups of 4, and then randomly assigned to diets based on alfalfa silage containing 4 levels of dried molasses (trial 1) or liquid molasses (trial 2). In both studies, production data were collected for 8 wk, ruminal samples were taken in wk 4 and 8, and statistical models were used that included covariate means and block. In trial 1, experimental diets contained 18% CP and 0, 4, 8, or 12% dried molasses with 2.6, 4.2, 5.6, or 7.2% total sugar. With increasing sugar, there was a linear increase in dry matter intake (DMI), and digestibility of dry matter (DM) and organic matter (OM), but no effect on yield of milk or protein. This resulted in linear decreases in fat-corrected milk (FCM)/DMI and milk N/N-intake. There was a linear decrease in urinary N with increasing sugar, and quadratic effects on milk fat content, yield of fat and FCM, and ruminal ammonia. Mean optimum from these quadratic responses was 4.8% total sugar in these diets. In trial 2, experimental diets contained 15.6% crude protein (CP) and 0, 3, 6, or 9% liquid molasses with 2.6, 4.9, 7.4, or 10.0% total sugar, respectively. Again, there were linear declines in FCM/DMI and milk N/N-intake with increasing sugar, but quadratic responses for DMI, yield of milk, protein, and SNF, digestibility of neutral detergent fiber and acid detergent fiber, milk urea, urinary excretion of purine derivatives, and ruminal ammonia. Mean optimum from all quadratic responses in this trial was 6.3% total sugar. An estimate of an overall optimum, based on yield of fat and FCM (trial 1) and yield of milk, protein, and SNF (trial 2), was 5.0% total sugar, equivalent to adding 2.4% sugar to the basal diets. Feeding more than 6% total sugar appeared to depress production.

摘要

据报道，在奶牛日粮中添加糖可提高其生产性能。在两项试验中，分别将48头泌乳期荷斯坦奶牛（其中8头安装了瘤胃瘘管）饲喂协变量日粮2周，根据产奶天数分为12组，每组4头，然后根据含4种水平干糖蜜（试验1）或液体糖蜜（试验2）的苜蓿青贮饲料随机分配日粮。在两项研究中，均收集了8周的生产数据，在第4周和第8周采集瘤胃样本，并使用包含协变量均值和区组的统计模型。在试验1中，试验日粮粗蛋白含量为18%，干糖蜜水平分别为0%、4%、8%或12%，总糖含量分别为2.6%、4.2%、5.6%或7.2%。随着糖含量增加，干物质采食量（DMI）、干物质（DM）和有机物（OM）消化率呈线性增加，但对牛奶或蛋白质产量无影响。这导致校正乳（FCM）/DMI和牛奶氮/氮摄入量呈线性下降。随着糖含量增加，尿氮呈线性下降，对乳脂率、脂肪产量和FCM以及瘤胃氨有二次效应。这些二次反应的平均最佳总糖含量为4.8%。在试验2中，试验日粮粗蛋白含量为15.6%，液体糖蜜水平分别为分别为0%、3%、6%或9%，总糖含量分别为2.6%、4.9%、7.4%或10.0%。同样，随着糖含量增加，FCM/DMI和牛奶氮/氮摄入量呈线性下降，但DMI、牛奶产量、蛋白质和非脂固形物（SNF）产量、中性洗涤纤维和酸性洗涤纤维消化率、牛奶尿素、嘌呤衍生物尿排泄量和瘤胃氨有二次反应。该试验中所有二次反应的平均最佳总糖含量为6.3%。根据脂肪和FCM产量（试验1）以及牛奶、蛋白质和SNF产量（试验2）估算的总体最佳总糖含量为5.0%，相当于在基础日粮中添加2.4%的糖。总糖含量超过6%似乎会降低生产性能。