This study aimed to evaluate levels of yerba mate (Ilex paraguariensis) extract (YME), as a feed additive in the diets of growing lambs on serum biochemical parameters and hematological indices, animal performance, body metrics and carcass traits. Thirty-six entire (nine per treatment), male growing lambs, weighing 23.8 ± 3.7 kg, were fed the experimental diets which were treatments consisting of increasing levels of YME (0, 1, 2, and 4% inclusion on a dry matter [DM] basis) during an experimental period of 53 days. The experiment was carried out in a randomized block design, which initial body weight was used as blocking factor and the results were analyzed by orthogonal contrasts (linear, quadratic, and cubic). Yerba mate extract did not change the general health status of the animals; however, inclusions of up to 2% of the extract increased globulins (p = 0.05) and white blood cell count, as segmented neutrophils (p = 0.02) and lymphocytes (p = 0.04). Additionally, inclusion of up to 2% YME increased dry matter intake, final weight gain, total and daily gain (p < 0.05), also tended to increase ribeye area and reduce fat thickness (p < 0.10); however, YME above 2% of inclusion reduced animal productive parameters (p < 0.05). In conclusion, levels up to 2% of YME were beneficial to the health and productive parameters of growing lambs.

中文翻译：

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在生长羔羊的日粮中添加大叶杨提取物：对血液参数，动物生产性能和Car体性状的影响。

这项研究旨在评估yerba mate（冬瓜（Ilex paraguariensis））提取物（YME），作为成年羔羊饮食中的饲料添加剂，其血清生化参数和血液学指标，动物生长性能，身体指标和car体性状 饲喂三十六只完整的（每只处理九只）雄性成年羔羊，重23.8±3.7公斤，饲喂实验性日粮，包括增加YME水平（干物质中0、1、2和4％的夹杂物[ DM]基础）在53天的实验期内。实验采用随机区组设计进行，初始体重被用作区组因子，并通过正交对比（线性，二次和三次）分析结果。Yerba mate提取物不会改变动物的总体健康状况；但是，提取物中最多2％的夹杂物会增加球蛋白（p= 0.05）和白细胞计数，分别为中性粒细胞（p = 0.02）和淋巴细胞（p = 0.04）。此外，最多添加2％的YME可以增加干物质摄入量，最终体重增加，总和每日增加量（p <0.05），也往往会增加肋眼面积并减少脂肪厚度（p <0.10）。然而，YME含量大于2％会降低动物生产参数（p <0.05）。总之，高达2％的YME水平有利于生长羔羊的健康和生产参数。