Enterotoxigenic Escherichia coli (ETEC) is the aetiological agent of postweaning diarrhoea (PWD) in piglets. The SNPs located on the Mucine 4 (MUC4) and Fucosyltransferase 1 (FUT1) genes have been associated with the susceptibility to ETEC F4 and ETEC F18, respectively. The interplay between the MUC4 and FUT1 genotypes to ETEC infection and the use of amoxicillin in modifying the intestinal microbiota during a natural infection by multiresistant ETEC strains have never been investigated. The aim of this study was to evaluate the effects of the MUC4 and FUT1 genotypes and the administration of amoxicillin through different routes on the presence of diarrhoea and the faecal microbiota composition in piglets naturally infected with ETEC. Seventy-one piglets were divided into three groups: two groups differing by amoxicillin administration routes-parenteral (P) or oral (O) and a control group without antibiotics (C). Faecal scores, body weight, presence of ETEC F4 and F18 were investigated 4 days after the arrival in the facility (T0), at the end of the amoxicillin administration (T1) and after the withdrawal period (T2). The faecal bacteria composition was assessed by sequencing the 16S rRNA gene. We described that MUC4 and FUT1 genotypes were associated with the presence of ETEC F4 and ETEC F18. The faecal microbiota was influenced by the MUC4 genotypes at T0. We found the oral administration to be associated with the presence of diarrhoea at T1 and T2. Furthermore, the exposure to amoxicillin resulted in significant alterations of the faecal microbiota. Overall, MUC4 and FUT1 were confirmed as genetic markers for the susceptibility to ETEC infections in pigs. Moreover, our data highlight that group amoxicillin treatment may produce adverse outcomes on pig health in course of multiresistant ETEC infection. Therefore, alternative control measures able to maintain a healthy faecal microbiota in weaners are recommended.

中文翻译：

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宿主基因型和阿莫西林给药影响天然多重耐药 ETEC 感染期间断奶仔猪腹泻和粪便微生物群的发生率

产肠毒素大肠杆菌 (ETEC) 是仔猪断奶后腹泻 (PWD) 的病原体。位于粘蛋白 4 (MUC4) 和岩藻糖基转移酶 1 (FUT1) 基因上的 SNP 分别与对 ETEC F4 和 ETEC F18 的易感性相关。从未研究过 MUC4 和 FUT1 基因型与 ETEC 感染之间的相互作用，以及在多重耐药 ETEC 菌株自然感染期间使用阿莫西林改变肠道微生物群。本研究的目的是评估 MUC4 和 FUT1 基因型以及通过不同途径施用阿莫西林对自然感染 ETEC 的仔猪腹泻和粪便微生物群组成的影响。71头仔猪被分为三组：两组因阿莫西林给药途径不同 - 肠胃外 (P) 或口服 (O) 和没有抗生素的对照组 (C)。在到达设施后 4 天 (T0)、阿莫西林给药结束时 (T1​​) 和停药期后 (T2) 调查粪便评分、体重、ETEC F4 和 F18 的存在。通过对 16S rRNA 基因进行测序来评估粪便细菌组成。我们描述了 MUC4 和 FUT1 基因型与 ETEC F4 和 ETEC F18 的存在相关。粪便微生物群受 T0 时 MUC4 基因型的影响。我们发现口服给药与 T1 和 T2 时出现腹泻有关。此外，接触阿莫西林会导致粪便微生物群发生显着改变。全面的，MUC4 和 FUT1 被确认为猪 ETEC 感染易感性的遗传标记。此外，我们的数据强调，在多重耐药 ETEC 感染过程中，阿莫西林组治疗可能会对猪的健康产生不利影响。因此，建议采用能够维持断奶仔猪健康粪便微生物群的替代控制措施。