ABSTRACT

1. Two series of studies were conducted to determine the effects of a combination of ground plant material derived from Quillaja saponaria trees and Yucca schidigera plants (QY) as sources of saponin, on performance, productivity, nutrient digestibility and ileal morphology of growing broilers. In each trial, 480 Cobb male birds were allocated equally to 24 pens at one-day-of-age according to body weight

2. The studies consisted of two identical floor pen trials in which performance and nutrient digestibility were assessed and two trials where performance and ileal morphology were determined. In each trial, 0, 250 or 500 ppm QY were included in feed given to the broilers from 1–35 or 1–42 d of age, respectively. Eight (digestibility) or 12 (morphology) randomised replicate pens were used.

3. In the digestibility trials, two birds per pen were moved to metabolism cages at d 21. Excreta was collected for a five-day period (d 21 to 25) for the determination of apparent total tract digestibility of dry and organic matter, fat and ash and nitrogen retention. For intestinal morphology, ileal segments were collected from four birds/pen on d 21 to determine villus height and crypt depth. Performance data were collected in each trial series.

4. Results showed that feeding graded levels of QY produced significant linear improvements in performance and productivity at d 35, and similar linear effects were observed for N retention and all apparent digestibility measurements. Morphology data showed that birds receiving 250 and 500 ppm QY had significantly increased villus height

5. These results indicated that QY exerted a positive influence on the intestinal tract by increasing the absorptive surface and improving nutrient digestibility. These effects were considered to be associated with the performance improvements recorded in both experiments.

摘要

1. 进行了两个系列的研究，以确定来自皂角树和丝兰植物 (QY) 的地面植物材料组合作为皂苷来源对生长肉鸡的生产性能、生产力、养分消化率和回肠形态的影响。在每个试验中，480 只 Cobb 雄性鸡在 1 日龄时根据体重平均分配到 24 个围栏中

2. 研究包括两个相同的落地围栏试验，其中评估性能和养分消化率，两个试验确定性能和回肠形态。在每个试验中，1-35 日龄或 1-42 日龄的肉鸡饲料中分别添加了 0、250 或 500 ppm QY。使用了 8 个（消化率）或 12 个（形态）随机复制笔。

3. 在消化率试验中，每栏 2 只鸡在 21 天时被转移到新陈代谢笼中。收集排泄物 5 天（21 至 25 天），用于测定干物质和有机物质、脂肪的表观总消化道消化率和灰分和氮保留。对于肠道形态，在第 21 天从四只鸟/围栏收集回肠段以确定绒毛高度和隐窝深度。在每个试验系列中收集性能数据。

4. 结果表明，饲喂分级水平的 QY 在 35 天时对生产性能和生产力产生了显着的线性改善，并且在 N 保留和所有表观消化率测量中观察到类似的线性效应。形态学数据显示，接受 250 和 500 ppm QY 的鸡的绒毛高度显着增加

5.这些结果表明，QY通过增加吸收表面和提高营养消化率对肠道产生积极影响。这些影响被认为与两个实验中记录的性能改进有关。