Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria.
Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, Veterinaerplatz 1, 1210 Vienna, Austria; Directorate General of Human Resource for Science, Technology, and Higher Education-Indonesia, 10270 Jakarta, Indonesia.
J Dairy Sci. 2018 Apr;101(4):3085-3098. doi: 10.3168/jds.2017-14051. Epub 2018 Feb 7.
A new segment of feed industry based on bakery by-products (BBP) has emerged. Yet, information is lacking regarding the effects of inclusion of BBP in ruminant diets on ruminal fermentation and microbiota. Therefore, the aim of this study was to evaluate the effect of the gradual replacement of grains by BBP on ruminal fermentation, nutrient degradation, and microbial community composition using the rumen-simulation technique. All diets consisted of hay and concentrate mixture with a ratio of 42:58 (dry matter basis), but differed in the concentrate composition with either 45% cereal grains or BBP, whereby 15, 30, or 45% of BBP were used in place of cereal grains. The inclusion of increasing levels of BBP in the diet linearly enhanced ruminal degradation of starch from 84% (control) to 96% (45% BBP), while decreasing degradation of crude protein and fiber. The formation of methane was lowered in the 45% BBP diet compared with all other diets. Whereas the ammonia concentration was similar in the control and 15% BBP, a significant decrease was found in 30% BBP (-23%) and 45% BBP (-33%). Also, BBP feeding shifted fermentation profile toward propionate at the expense of acetate. Moreover, isobutyrate linearly decreased with increasing BBP inclusion. Bacterial 16S rRNA Illumina MiSeq (Microsynth AG, Balach, Switzerland) sequencing revealed a decreased microbial diversity for the 45% BBP diet. Furthermore, the replacement of cereal grains with BBP went along with an increased abundance of the genera Prevotella, Roseburia, and Megasphaera, while decreasing Butyrivibrio and several OTU belonging to Ruminococcaceae. In conclusion, the inclusion of BBP at up to 30% of the dry matter had no detrimental effects on pH, fiber degradability, and microbial diversity, and enhanced propionate production. However, a higher replacement level (45%) impaired ruminal fermentation traits and fiber degradation and is not recommended.
以烘焙副产物（BBP）为基础的饲料行业新领域已经出现。然而，关于在反刍动物日粮中添加 BBP 对瘤胃发酵和微生物群的影响，信息还很缺乏。因此，本研究旨在使用瘤胃模拟技术，评估逐渐用 BBP 替代谷物对瘤胃发酵、养分降解和微生物群落组成的影响。所有日粮均由干草和精料混合物组成，比例为 42:58（干物质基础），但精料组成不同，含有 45%的谷物或 BBP，其中 15%、30%或 45%的 BBP 替代谷物。日粮中 BBP 水平的增加线性提高了淀粉的瘤胃降解率，从 84%（对照）提高到 96%（45% BBP），而粗蛋白和纤维的降解则降低。与所有其他日粮相比，45% BBP 日粮中甲烷的形成降低。尽管对照和 15% BBP 日粮中的氨浓度相似，但在 30% BBP（-23%）和 45% BBP（-33%）中发现显著降低。此外，BBP 喂养使发酵谱向丙酸转移，以牺牲乙酸为代价。而且，随着 BBP 含量的增加，异丁酸线性减少。细菌 16S rRNA Illumina MiSeq（Microsynth AG，Balach，瑞士）测序显示，45% BBP 日粮的微生物多样性降低。此外，用 BBP 替代谷物伴随着普雷沃氏菌属、罗氏菌属和巨球形菌属的丰度增加，而丁酸弧菌和属于 Ruminococcaceae 的几个 OTU 的丰度降低。总之，在干物质中添加高达 30%的 BBP 对 pH、纤维降解率和微生物多样性没有不利影响，并提高了丙酸的产生。然而，更高的替代水平（45%）会损害瘤胃发酵特性和纤维降解，因此不推荐使用。
