ABSTRACT Two experiments were conducted to evaluate the inclusion of feed enzymes into beef cattle creep feeds. In the first one, the following treatments were tested in vitro: (1) 100% bermudagrass (GRASS); (2) a mixture of 75% bermudagrass and 25% creep feed (CREEP); (3) CREEP enhanced with endo-1,4-β-xylanase (XYLAN); (4) CREEP enhanced with endo-1,3(4)-β-glucanase (BGLUC). Degradation of fibre was greatest (P ≤ 0.03) for BGLUC, whereas in vitro dry matter digestibility was greatest (P = 0.01) for XYLAN. In the second experiment, cow-calf pairs from 2 farms were split into 3 groups: (1) Group with no supplementation of calves (NO FEED); (2) Group where calves were supplemented in a creep feeding system (PLAIN FEED); and (3) Same feed regimen as PLAIN FEED, but with the addition of endo-1,4-β-xylanase due to the positive results observed in experiment 1 (ENZYME FEED). There was a numerical increase in calf average daily gain in the 2 groups that were supplemented, however, only ENZYME FEED was significantly different (P ≤ 0.03) than NO FEED. At one farm, supplement gain:feed was improved (P = 0.01) in ENZYME FEED, compared to PLAIN FEED. Collectively, these results indicate that xylanase can be used to enhance beef cattle creep feeds.

中文翻译：

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外源酶在肉牛蠕动饲料中的应用

摘要 进行了两个实验来评估饲料酶在肉牛蠕变饲料中的加入。在第一个中，体外测试了以下处理： (1) 100% 狗牙根 (GRASS)；(2) 75% 狗牙根和 25% 蠕变饲料 (CREEP) 的混合物；(3) 用内切 1,4-β-木聚糖酶 (XYLAN) 增强 CREEP；(4) 用内切 1,3(4)-β-葡聚糖酶 (BGLUC) 增强 CREEP。BGLUC 的纤维降解最大 (P ≤ 0.03)，而 XYLAN 的体外干物质消化率最大 (P = 0.01)。在第二个实验中，来自 2 个农场的牛犊被分成 3 组：（1）小牛不补充组（NO FEED）；(2) 犊牛在幼崽饲喂系统 (PLAIN FEED) 中进行补充的组；(3) 与 PLAIN FEED 相同的喂养方案，但添加了 Endo-1，4-β-木聚糖酶由于在实验 1 (ENZYME FEED) 中观察到的阳性结果。在补充的 2 组中，犊牛平均日增重在数值上有所增加，但是，只有酶饲料与无饲料有显着差异（P ≤ 0.03）。在一个农场，与普通饲料相比，酶饲料的补充增重：饲料得到改善（P = 0.01）。总的来说，这些结果表明木聚糖酶可用于增强肉牛的饲料。