ABSTRACT

In this study, the effects of dietary fibre and types of indigestible markers (IM) on the apparent total tract digestibility (ATTD) of gross energy (GE) and nutrients as well as IM recovery in diets fed to growing pigs were investigated. A total of 30 barrows (initial body weight 40.5 ± 1.4 kg) were allotted to five experimental diets, based on a completely randomised block design, with body weight as a blocking factor. The five diets comprised a corn–soya bean meal basal diet, and four diets in which sugar beet pulp (SBP) or defatted rice bran (DFRB) partly replaced 10% or 20% of corn, soya bean meal and soya bean oil in the basal diet. All diets were formulated to contain two types of IM, namely 0.5% chromic oxide (Cr) and 1.0% celite as the source of acid-insoluble ash (AIA). Animals were subjected to a 7-d adaptation period, and their faeces were collected over a 5-d period using the total faecal collection (TC) method. Results showed that the AIA method determined similar ATTD of GE and nutrients as the TC method. Values of dietary nutrients determined via AIA and TC methods were significantly higher than those obtained by Cr (p < 0.05). The ATTD of GE and nutrients linearly decreased with an increased inclusion level of SBP or DFRB (p < 0.01), whereas recoveries of AIA and Cr were not affected by the aforementioned inclusions. Results from the faecal analysis revealed that AIA recovery (90.5%) was significantly higher than that of Cr (84.9%, p < 0.05), while diets with DFRB (91.3%) had significantly greater IM recovery rates than those with SBP (84.4%, p < 0.05). In conclusion, the type of dietary fibre, rather than the level, significantly affects IM recovery. Notably, AIA should be preferred to Cr when using the IM method to determine ATTD of GE and nutrients for diets in growing pigs.

摘要

在这项研究中，研究了日粮纤维和难消化标志物类型 (IM) 对生长猪日粮中总能量 (GE) 和营养素的表观全消化道消化率 (ATTD) 以及 IM 恢复的影响。基于完全随机的区组设计，将总共 30 头手推车（初始体重 40.5 ± 1.4 kg）分配到五种实验日粮中，体重作为阻断因素。5 种日粮包括玉米-豆粕基础日粮，以及 4 种日粮，其中甜菜浆 (SBP) 或脱脂米糠 (DFRB) 部分替代了 10% 或 20% 的玉米、豆粕和大豆油。基础饮食。所有日粮均含有两种类型的 IM，即 0.5% 氧化铬 (Cr) 和 1.0% 硅藻土作为酸不溶性灰分 (AIA) 的来源。动物经历了7天的适应期，并使用总粪便收集（TC）方法在 5 天的时间内收集了他们的粪便。结果表明，AIA 方法测定的 GE 和营养素的 ATTD 与 TC 方法相似。通过 AIA 和 TC 方法测定的日粮营养素值显着高于 Cr（p < 0.05)。GE 和营养物质的 ATTD 随着 SBP 或 DFRB 夹杂物含量的增加呈线性下降（p < 0.01），而 AIA 和 Cr 的回收率不受上述夹杂物的影响。粪便分析结果显示，AIA 回收率 (90.5%) 显着高于 Cr (84.9%, p < 0.05)，而 DFRB (91.3%) 的 IM 回收率显着高于 SBP (84.4%) , p < 0.05)。总之，膳食纤维的类型，而不是水平，显着影响 IM 恢复。值得注意的是，当使用 IM 方法确定生长猪日粮的 GE 和营养物质的 ATTD 时，AIA 应优于 Cr。