Whon Tae Woong, Kim Hyun Sik, Shin Na-Ri, Sung Hojun, Kim Min-Soo, Kim Joon Yong, Kang Woorim, Kim Pil Soo, Hyun Dong-Wook, Seong Hoon Je, Sul Woo Jun, Roh Seong Woon, Bae Jin-Woo
Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University, Seoul, Republic of Korea.
Microbiology and Functionality Research Group, World Institute of Kimchi, Gwangju, Republic of Korea.
mSystems. 2021 Mar 2;6(2):e00816-20. doi: 10.1128/mSystems.00816-20.
Neonatal calf diarrhea is a common disease leading to a major economic loss for cattle producers worldwide. Several infectious and noninfectious factors are implicated in calf diarrhea, but disease control remains problematic because of the multifactorial etiology of the disease. Here, we conducted diagnostic multiplex PCR assay and meta-omics analysis (16S rRNA gene-based metataxonomics and untargeted transcriptional profiling) of rectal content of normal and diarrheic beef calves (= 111). In the diarrheic calf gut, we detected both microbial compositional dysbiosis (i.e., increased abundances of the family members and their lytic bacteriophages) and functional dysbiosis (i.e., elevated levels of aerobic respiration and virulence potential). The calf diarrheic transcriptome mirrored the gene expression of the bovine host and was enriched in cellular pathways of sulfur metabolism, innate immunity, and gut motility. We then isolated 12 nontoxigenic strains from the gut of diarrheic calves. Feeding a strain mixture to preweaning mice resulted in a significantly higher level of fecal moisture content, with decreased body weight gain and shortened colon length. The presented findings suggest that gut inflammation followed by a prolonged expansion of nontoxigenic autochthonous contributes to the onset of diarrhea in preweaning animals. Calf diarrhea is the leading cause of death of neonatal calves worldwide. Several infectious and noninfectious factors are implicated in calf diarrhea, but disease control remains problematic because of the multifactorial etiology of the disease. The major finding of the current study centers around the observation of microbial compositional and functional dysbiosis in rectal samples from diarrheic calves. These results highlight the notion that gut inflammation followed by a prolonged expansion of autochthonous contributes to the onset of calf diarrhea. Moreover, this condition possibly potentiates the risk of invasion of notorious enteric pathogens, including spp., and the emergence of inflammation-resistant (or antibiotic-resistant) microbiota via active horizontal gene transfer mediated by lytic bacteriophages.
新生犊牛腹泻是一种常见疾病，给全球养牛业造成重大经济损失。犊牛腹泻涉及多种传染性和非传染性因素，但由于该病病因多因素，疾病控制仍然存在问题。在此，我们对正常和腹泻肉牛犊（n = 111）的直肠内容物进行了多重PCR诊断分析和宏组学分析（基于16S rRNA基因的宏分类学和非靶向转录谱分析）。在腹泻犊牛肠道中，我们检测到微生物组成失调（即某些菌属及其裂解性噬菌体丰度增加）和功能失调（即有氧呼吸水平和毒力潜力升高）。犊牛腹泻转录组反映了牛宿主的基因表达，并在硫代谢、先天免疫和肠道蠕动的细胞途径中富集。然后，我们从腹泻犊牛肠道中分离出12株非产毒菌株。将菌株混合物喂给断奶前小鼠，导致粪便水分含量显著升高，并伴有体重增加减少和结肠长度缩短。研究结果表明，肠道炎症随后非产毒本土菌的长期扩张导致断奶前动物腹泻发作。犊牛腹泻是全球新生犊牛死亡的主要原因。犊牛腹泻涉及多种传染性和非传染性因素，但由于该病病因多因素，疾病控制仍然存在问题。当前研究的主要发现集中在对腹泻犊牛直肠样本中微生物组成和功能失调的观察。这些结果突出了这样一种观点，即肠道炎症随后本土菌的长期扩张导致犊牛腹泻发作。此外，这种情况可能会增加包括某些菌属在内的臭名昭著的肠道病原体入侵的风险，以及通过裂解性噬菌体介导的活跃水平基因转移出现抗炎症（或抗生素抗性）微生物群的风险。
