High-Throughput Sequencing of Nontuberculous Mycobacterial Flora and Mycobacterium abscessus in Cattle

Nontuberculous mycobacteria (NTM) are environmental organisms that can cause opportunistic infections in humans and animals. <i>Mycobacterium abscessus</i> (Mab) is a rapidly growing <i>Mycobacterium</i> known for its resistance to multiple antibiotics and ability to cause respiratory, skin, and mucosal infections. Understanding the distribution and prevalence of NTM, particularly Mab, in cattle farms and slaughterhouses is crucial for developing effective prevention and control measures. We collected environmental swabs from various surfaces (e.g., feed troughs, sinks, walls, floors, feces, and padding) in cattle farms and slaughterhouses across multiple provinces. High-throughput sequencing technology was utilized to analyze the 16S rDNA V3-V4 region of bacterial DNA extracted from the samples, and qPCR methods were employed to detect and quantify <i>Mycobacterium abscessus</i> in the collected samples. Bioinformatics analysis was performed to identify and classify the NTM species present in the samples. This study compared the abundance and diversity of NTM in different environments and assessed the potential zoonotic risk. A total of 1648 environmental swabs were collected from cattle farms and slaughterhouses in 12 provinces of China in 2023, of which 12 samples tested positive for Mab qPCR detection, yielding a detection rate of 0.73% (12/1648). Among them, the detection rate of environmental samples from cattle farms and slaughterhouses was 0.42% (3/720) and 0.87% (9/928), respectively. This study provides valuable information on the epidemiology of NTM in cattle farms and slaughterhouses, contributing to developing effective strategies for preventing and controlling NTM infections. It also enhances our understanding of the zoonotic potential of <i>Mycobacterium abscessus</i> and other NTM species.