Enrofloxacin is an important antibiotic used for prevention and treatment of Salmonella infection in poultry in many countries. However, oral administration of enrofloxacin may lead to the alterations in the microbiota and metabolome in the chicken intestine, thereby reducing colonization resistance to the Salmonella infection. To study the effect of enrofloxacin on Salmonella in the chicken cecum, we used different concentrations of enrofloxacin to feed 1-day-old chickens, followed by oral challenge with Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium). We then explored the distribution pattern of S. Typhimurium in cecum contents in vivo and analyzed the microbial community structure of cecum contents using microbial 16S amplicon sequencing. Untargeted metabolomics was used to explore the gut metabolome on day 14. Faecalibacterium and Anaerostipes, which are closely related to the chicken intestinal metabolome, were screened using a multi-omics technique. The abundance of S. Typhimurium was significantly higher in the enrofloxacin-treated group than in the untreated group, and S. Typhimurium persisted longer. Moreover, the cecal colony structures of the three groups exhibited different characteristics, with Lactobacillus reaching its highest abundance on day 21. Notably, S. Typhimurium infection is known to affect the fecal metabolome of chickens differently. Thus, our results suggested that enrofloxacin and Salmonella infections completely altered the intestinal microbiota and metabolism of chickens.

中文翻译：

---

恩诺沙星改变肠道微生物群和代谢谱并阻碍肠道沙门氏菌亚种的恢复。新生鸡的肠道鼠伤寒血清型感染。

恩诺沙星是许多国家用于预防和治疗家禽沙门氏菌感染的重要抗生素。然而，口服恩诺沙星可能会导致鸡肠道微生物群和代谢组的改变，从而降低对沙门氏菌感染的定植抵抗力。为了研究恩诺沙星对鸡盲肠中沙门氏菌的影响，我们使用不同浓度的恩诺沙星喂养 1 日龄鸡，然后口服沙门氏菌肠道亚种。肠道鼠伤寒沙门氏菌（S.鼠伤寒沙门氏菌）。然后，我们探索的分布格局S.鼠伤寒沙门氏菌在盲肠内容体内并使用微生物 16S 扩增子测序分析盲肠内容物的微生物群落结构。在第 14 天使用非靶向代谢组学探索肠道代谢组。使用多组学技术筛选与鸡肠道代谢组密切相关的粪杆菌和厌氧菌。的丰度S.鼠伤寒沙门氏菌是恩氟沙星治疗组中比在未处理组显著更高，S.鼠伤寒沙门氏菌持续更长的时间。此外，三组的盲肠菌落结构表现出不同的特征，乳酸杆菌在第 21 天达到最高丰度。众所周知，鼠伤寒感染对鸡的粪便代谢组有不同的影响。因此，我们的结果表明，恩诺沙星和沙门氏菌感染完全改变了鸡的肠道微生物群和代谢。