Zhang Xia, Xu Dongmei, Su Rina, Li Fuhou, Chen Hu, Jia Mengya, Chen Mengyan, Guo Xusheng
School of Life Sciences, Lanzhou University, Lanzhou, China.
Probiotics and Life Health Research Institute, Lanzhou University, Lanzhou, China.
Front Microbiol. 2025 May 19;16:1494538. doi: 10.3389/fmicb.2025.1494538. eCollection 2025.
Antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) have attracted more attentions in fermented feed recently. However, little information is available on the occurrence and distribution of ARGs in ensiled forages in the alpine region of the Qinghai-Tibetan plateau (QTP) with an extremely harsh environment.
The study investigated the distribution and spread mechanism of ARB and ARGs in silage along 2600 m (low), 3600 m (medium) and 4600 m (high) altitude in the QTP.
The major ARG types in silage were multidrug, aminoglycoside, bacitracin, beta-lactam and polymyxin, while tnpA and IS91 were the dominant mobile genetic elements (MGEs) subtypes in the silage. The dominant ARGs were mainly carried by . Although altitudinal gradient had no influence on the diversity or abundance of other ARGs and MGEs in the silage ( > 0.05), the network co-occurrence patterns among ARGs, MGEs, and bacteria in high-altitude silage were more complex than that in low- and medium-altitude silages. The dominant clinical ARGs in the alpine silage were bacA and acrF, and the abundance of clinical ARGs decreased with prolonged fermentation time.
This study provides important data on the status of ARGs in ensiled forage from the alpine region of the QTP.
抗生素抗性基因（ARGs）和抗生素抗性细菌（ARB）最近在发酵饲料中受到了更多关注。然而，关于青藏高原（QTP）高寒地区青贮饲料中ARGs的发生和分布的信息却很少，该地区环境极其恶劣。
本研究调查了QTP地区海拔2600米（低）、3600米（中）和4600米（高）的青贮饲料中ARB和ARGs的分布及传播机制。
青贮饲料中的主要ARG类型为多药抗性、氨基糖苷类、杆菌肽、β-内酰胺和多粘菌素，而tnpA和IS91是青贮饲料中主要的移动遗传元件（MGEs）亚型。优势ARGs主要由……携带。尽管海拔梯度对青贮饲料中其他ARGs和MGEs的多样性或丰度没有影响（P>0.05），但高海拔青贮饲料中ARGs、MGEs和细菌之间的网络共现模式比低海拔和中海拔青贮饲料更为复杂。高寒青贮饲料中的主要临床ARGs为bacA和acrF，且临床ARGs的丰度随发酵时间延长而降低。
本研究提供了关于QTP高寒地区青贮饲料中ARGs状况的重要数据。
