Pascual A, Pauletto M, Giantin M, Radaelli G, Ballarin C, Birolo M, Zomeño C, Dacasto M, Bortoletti M, Vascellari M, Xiccato G, Trocino A
1Department of Comparative Biomedicine and Food Science (BCA), University of Padova, Viale dell'Università 16, I-35020 Legnaro, Padova Italy.
2Department of Agronomy, Food, Natural Resources, Animal, and Environment (DAFNAE), University of Padova, Viale dell'Università 16, I-35020 Legnaro, Padova Italy.
J Anim Sci Biotechnol. 2020 May 1;11:40. doi: 10.1186/s40104-020-00448-z. eCollection 2020.
The dietary supplementation of yeast cell wall extracts (YCW) has been found to reduce pathogenic bacteria load, promote immunoglobulin production, prevent diseases by pro-inflammatory responses, and alter gut microbiota composition. This study evaluated growth and slaughter results, health, gut morphology, immune status and gut transcriptome of 576 male chickens fed two diets, i.e. C (control) or Y (with 250-500 g/t of YCW fractions according to the growth period). At 21 and 42 d the jejunum of 12 chickens per diet were sampled and stained with hematoxylin/eosin for morphometric evaluation, with Alcian-PAS for goblet cells, and antibodies against CD3+ intraepithelial T-cells and CD45+ intraepithelial leukocytes. The jejunum sampled at 42 d were also used for whole-transcriptome profiling.
Dietary YCW supplementation did not affect final live weight, whereas it decreased feed intake (114 to 111 g/d; 0.10) and improved feed conversion (1.74 to 1.70; ≤ 0.01). Regarding the gut, YCW supplementation tended to increase villi height ( = 0.07); it also increased the number of goblet cells and reduced the density of CD45+ cells compared to diet C ( < 0.001). In the gut transcriptome, four genes were expressed more in broilers fed diet Y compared to diet C, i.e. cytochrome P450, family 2, subfamily C, polypeptide 23b (), tetratricopeptide repeat domain 9 (), basic helix-loop-helix family member e41 (), and the metalloreductase . Only one gene set (HES_PATHWAY) was significantly enriched among the transcripts more expressed in broilers fed diet Y. However, a total of 41 gene sets were significantly over-represented among genes up-regulated in control broilers. Notably, several enriched gene sets are implicated in immune functions and related to NF-κB signaling, apoptosis, and interferon signals.
The dietary YCW supplementation improved broiler growth performance, increased gut glycoconjugate secretion and reduced the inflammatory status together with differences in the gut transcriptome, which can be considered useful to improve animal welfare and health under the challenging conditions of intensive rearing systems in broiler chickens.
已发现膳食补充酵母细胞壁提取物（YCW）可降低病原菌载量、促进免疫球蛋白产生、通过促炎反应预防疾病以及改变肠道微生物群组成。本研究评估了576只雄性鸡的生长和屠宰结果、健康状况、肠道形态、免疫状态和肠道转录组，这些鸡饲喂两种日粮，即C（对照）或Y（根据生长阶段添加250 - 500 g/t的YCW组分）。在21日龄和42日龄时，每种日粮选取12只鸡的空肠进行采样，用苏木精/伊红染色进行形态计量学评估，用阿尔辛 - PAS染色观察杯状细胞，并用抗CD3 +上皮内T细胞和抗CD45 +上皮内白细胞抗体进行检测。42日龄时采样的空肠也用于全转录组分析。
日粮添加YCW不影响最终活重，但降低了采食量（从114降至111 g/d；P = 0.10）并改善了饲料转化率（从1.74降至1.70；P≤0.01）。关于肠道，添加YCW倾向于增加绒毛高度（P = 0.07）；与日粮C相比，它还增加了杯状细胞数量并降低了CD45 +细胞密度（P < 0.001）。在肠道转录组中，与日粮C相比，饲喂日粮Y的肉鸡中有四个基因表达更多，即细胞色素P450家族2亚家族C多肽23b（CYP2C23b）、四肽重复结构域9（TTC9）、碱性螺旋 - 环 - 螺旋家族成员e41（BHLHE41）和金属还原酶（MTRR）。在饲喂日粮Y的肉鸡中表达较多的转录本中，只有一个基因集（HES_PATHWAY）显著富集。然而，在对照肉鸡上调的基因中，共有41个基因集显著过度表达。值得注意的是，几个富集的基因集与免疫功能有关，并且与NF - κB信号传导、细胞凋亡和干扰素信号有关。
日粮添加YCW改善了肉鸡的生长性能，增加了肠道糖缀合物分泌并降低了炎症状态，同时肠道转录组也存在差异，这在肉鸡集约化饲养系统的挑战性条件下可被认为有助于改善动物福利和健康。
