Wang Weiwei, Chen Yiliang, Ye Hui, Dong Zemin, Zhang Changming, Feng Dingyuan, Cao Qingyun, Liang Shujie, Zuo Jianjun
Guangdong Provincial Key Laboratory of Animal Nutrition Control, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China.
Anim Nutr. 2023 Jul 12;14:334-342. doi: 10.1016/j.aninu.2023.04.010. eCollection 2023 Sep.
This study aimed to investigate the potential mitigating effects of N-acyl homoserine lactonase (AHLase) on the virulence of and its induction of intestinal damages in broilers. In vitro study was firstly conducted to examine if AHLase treatment could attenuate the virulence of . Then, an in vivo experiment was performed by allocating 240 broiler chicks at 1 d old into 3 groups (8 replicates per group): negative control (NC), positive control (PC), and PC supplemented with 10,000 U/kg AHLase. All chicks except those in NC were orally challenged by from 8 to 10 d of age. Parameters were measured on d 11 and 21. The results showed that treatment with 1 U/mL AHLase suppressed the biofilm-forming ability (including biofilm biomass, extracellular DNA secretion and biofilm formation-related gene expression), together with swarming motility and adhesive capacity of . Supplemental 10,000 U/kg AHLase counteracted -induced impairments ( < 0.05) in broiler growth performance (including final body weight, average daily gain and average daily feed intake) during either 1-11 d or 12-21 d, and increases ( < 0.05) in the indexes of liver, spleen and bursa of Fabricius on d 11, together with reductions ( < 0.05) in ileal villus height and its ratio to crypt depth on both d 11 and 21. AHLase addition also normalized the increased ( < 0.05) mRNA expression of ileal occludin on both d 11 and 21 in -challenged broilers. However, neither challenge nor AHLase addition altered ( > 0.05) serum diamine oxidase activity of broilers. Noticeably, challenge caused little change in the mRNA expression of ileal inflammatory cytokines except for an increase ( < 0.05) in interleukin-8 expression on d 11, whereas AHLase addition normalized ( < 0.05) this change. In conclusion, AHLase treatment could attenuate the virulence and pathogenicity of , thus contributing to alleviate -induced growth retardation and intestinal damages in broilers.
本研究旨在探讨N-酰基高丝氨酸内酯酶（AHLase）对肉鸡致病性及其诱导肠道损伤的潜在缓解作用。首先进行体外研究，以检验AHLase处理是否能减弱其致病性。然后，进行体内实验，将240只1日龄的肉鸡雏鸡分为3组（每组8个重复）：阴性对照组（NC）、阳性对照组（PC）和添加10000 U/kg AHLase的PC组。除NC组外，所有雏鸡在8至10日龄时经口接种。在第11天和第21天测量各项参数。结果表明，1 U/mL AHLase处理可抑制其生物膜形成能力（包括生物膜生物量、细胞外DNA分泌和生物膜形成相关基因表达），以及其群体运动性和黏附能力。在1至11天或12至21天期间，添加10000 U/kg AHLase可抵消其对肉鸡生长性能（包括终末体重、平均日增重和平均日采食量）的损害（P<0.05），并使第11天肝脏、脾脏和法氏囊指数增加（P<0.05），同时使第11天和第21天回肠绒毛高度及其与隐窝深度的比值降低（P<0.05）。添加AHLase还使受感染肉鸡在第11天和第21天回肠闭合蛋白mRNA表达的增加（P<0.05）恢复正常。然而，接种和添加AHLase均未改变（P>0.05）肉鸡血清二胺氧化酶活性。值得注意的是，接种除使第11天白细胞介素-8表达增加（P<0.05）外，对回肠炎性细胞因子mRNA表达影响不大，而添加AHLase使这种变化恢复正常（P<0.05）。总之，AHLase处理可减弱其毒力和致病性，从而有助于减轻其对肉鸡生长发育迟缓及肠道损伤的影响。
