Porcine transmissible gastroenteritis virus (TGEV) is an enteric coronavirus that has caused high morbidity and mortality of piglets worldwide. Previous studies have shown that the TGEV can lead to severe diarrhoea, vomiting and dehydration in 2-week-old piglets and weaned piglets, resulting in a large number of piglet deaths. Antimicrobial peptides have broad-spectrum antimicrobial activity and a strong killing effect on bacteria, especially on the drug-resistant pathogenic bacteria, and it has attracted broad concern. However, there are very few reports on the effect of APB-13 (an antimicrobial peptide) on the intestinal microbes of piglets infected with TGEV. In this study, 16S rRNA gene sequencing was used to compare the microbial phylum and the genus of piglet's enteric microorganism in different experimental groups, and to predict the metabolic function of the microbial flora. At the same time, the apparent digestibility of nutrients, digestive enzyme activity, daily weight gain and survival rate were also measured. TGEV infection could cause the imbalance of intestinal microbes in piglets, and increase of the relative abundance of Proteobacteria, and decrease of the relative abundance of Firmicutes, Bacteroidetes and Actinobacteri. With the addition of APB-13, this problem can be alleviated, which can reduce the relative abundance of Proteobacteria and improve the balance of intestinal microorganisms. At the microbial genus level, after adding APB-13, the relative abundance of Catenibacterium, Enterobacter and Streptococcus in the intestinal tract of piglets infected with TGEV showed significant decrease, while the relative abundance of Lactobacillus and Ruminococcus increased. Finally, we found that APB-13 can significantly increase the activity of digestive enzyme in the intestinal tract of piglet, thereby improving the apparent digestibility of nutrients and the growth performance of piglets. This study demonstrates that APB-13 can alleviate the adverse outcomes caused by TGEV infection by correcting the intestinal microbial disorders.

中文翻译：

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APB-13通过纠正仔猪肠道微生物紊乱来改善由TGEV感染引起的不良后果

猪传染性胃肠炎病毒 (TGEV) 是一种肠道冠状病毒，已导致全球仔猪高发病率和死亡率。以往研究表明，TGEV可导致2周龄仔猪和断奶仔猪出现严重腹泻、呕吐和脱水，导致大量仔猪死亡。抗菌肽具有广谱抗菌活性，对细菌特别是耐药病原菌有很强的杀灭作用，受到广泛关注。然而，关于 APB-13（一种抗菌肽）对感染 TGEV 的仔猪肠道微生物的影响的报道很少。本研究采用16S rRNA基因测序对不同实验组仔猪肠道微生物的微生物门和属进行比较，并预测微生物菌群的代谢功能。同时，还测量了营养物质的表观消化率、消化酶活性、日增重和成活率。TGEV感染可导致仔猪肠道微生物失衡，增加相对丰度。变形菌，厚壁菌门、拟杆菌门和放线菌的相对丰度降低。APB-13的加入可以缓解这一问题，降低变形菌的相对丰度，改善肠道微生物的平衡。在微生物属水平上，添加APB-13后，TGEV感染仔猪肠道中链状杆菌、肠杆菌和链球菌的相对丰度显着降低，而乳​​酸杆菌和瘤胃球菌的相对丰度显着降低。增加。最后，我们发现APB-13可以显着提高仔猪肠道消化酶的活性，从而提高养分的表观消化率和仔猪的生长性能。本研究表明，APB-13 可以通过纠正肠道微生物紊乱来缓解 TGEV 感染引起的不良后果。