PDF(Pubmed)
Abstract：
This study investigated the impact of dietary supplementation with hydrolyzed yeast (Kluyveromyces marxianus) on growth performance, humoral immunity, jejunal morphology, cecal microbiota and metabolic pathways in broilers raised at 45 kg/m2. A total of 1,176 mixed sex 1-day-old Ross 308 broilers were distributed into 42 pens and randomly assigned to either the control group, the control + 250 g hydrolyzed yeast (HY)/ton, 250HY group, or the control + 500 g HY/ton, 500HY group for 42 d. HY did not affect growth performance. However, HY reduced (P < 0.05) mortality at 25 to 35 d. Dietary HY lowered the heterophil/lymphocyte ratio and enhanced the villus height/crypt depth ratio and Newcastle disease titer (P < 0.05). Compared with HY250 and the control, HY500 upregulated (P < 0.05) IL-10. HY enhanced the α diversity, inferring the richness and evenness of the ceca microbiota. HY500 had greater β diversity than the control (P < 0.05). Six bacterial phyla, namely, Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Verrucomicrobia, and Cyanobacteria, were found. The relative abundance of Firmicutes was greater in the HY500 treatment group than in the HY250 and control groups. HY decreased the abundance of Actinobacteria. HY supplementation altered (P < 0.05) the abundance of 8 higher-level taxa consisting of 2 classes (Bacilli and Clostridia), 1 order (Lactobacillales), 1 family (Streptococcaceae), and five genera (Streptococcus, Lachnospiraceae_uc, Akkermansiaceae, PACO01270_g, and LLKB_g). HY500 improved (P < 0.05) the abundance of Bacilli, Clostridia, Lactobacillales, Streptococcaceae, Streptococcus, PACO01270_g, and Lachnospiraceae_uc, while HY250 enhanced (P < 0.05) the abundance of Akkermansiaceae and LLKB_g. HY improved the abundance of Lactobacillus and Akkermansia spp. Minimal set of pathway analyses revealed that compared with the control, both HY250 and HY500 regulated 20 metabolic pathways. These findings suggest that dietary K. marxianus hydrolysate, especially HY500, improved humoral immunity and jejunal morphology and beneficially altered the composition and metabolic pathways of the cecal microbiota in broilers raised at 45 kg/m2.
摘要：
这项研究调查了日粮补充水解酵母（Kluyveromycesmarxianus）对生长性能的影响，体液免疫,空肠形态学，肉鸡的盲肠微生物群和代谢途径以45kg/m2为生。将总共1,176只1天大的混合性别Ross308肉鸡分配到42个围栏中，并随机分配到对照组中，对照+250克水解酵母(HY)/吨，250HY组,或对照+500克HY/吨，500HY组42d。HY对生长性能没有影响。然而,HY降低了25至35d的死亡率（P<0.05）。日粮HY降低了异粒细胞/淋巴细胞比率，提高了绒毛高度/隐窝深度比率和新城疫滴度（P<0.05）。与HY250和对照相比，HY500上调(P<0.05)IL-10。HY增强了α多样性，推断盲肠微生物群的丰富度和均匀度。HY500的β多样性高于对照(P<0.05)。六个细菌门，即,Firmicutes,拟杆菌,变形杆菌,放线菌,Verrucomicrobia,和蓝细菌，被发现了。HY500治疗组的Firmicutes的相对丰度高于HY250和对照组。HY降低了放线菌的丰度。补充HY改变了（P<0.05）由2类（芽孢杆菌和梭菌）组成的8个高级分类群的丰度，1顺序（乳杆菌），1科（链球菌科），和五个属(链球菌，落叶松科_uc,Akkermansiaceae，PACO01270_g,和LLKB_g）。HY500提高了芽孢杆菌的丰度（P<0.05），梭菌,乳酸杆菌,链球菌科，链球菌,PACO01270_g,和落叶松科_uc，HY250提高了Akkermansiaceae和LLKB_g的丰度（P<0.05）。HY提高了乳杆菌和阿克曼杆菌属的丰度。最小的通路分析显示，与对照相比，HY250和HY500调节20个代谢途径。这些发现表明，饮食中的K.marxianus水解物，尤其是HY500，改善了体液免疫和空肠形态，并有益地改变了45kg/m2饲养的肉鸡的盲肠微生物群的组成和代谢途径。
