Fecal antibiotic resistance genes were transferred through the distribution of soil-lettuce-snail food chain

Abstract

Massive antibiotic resistance genes (ARG) were detected in the soil modi ed by manure, which may affect human life safety through the food chain. However, the transmission of ARGs through the soil-plant-animal food chain is still unclear. Therefore, this study used high-throughput quantitative PCR technology to explore the effects of pig manure application on ARGs and bacterial communities in soil, lettuce phyllosphere and snail excrement.The results showed that a total of 384 ARGs and 48 MEGs were detected in all samples after 75 days of incubation. The diversity of ARGs and MGEs in soil components increased signi cantly by 87.04%and 40%with the addition of pig manure. The absolute abundance of ARGs in the phyllosphere of lettuce was signi cantly higher than that of the control group, with a growth rate of 212.5%.Six common ARGs were detected between the three components of the fertilization group, indicating that there was internal transmission of fecal ARGs between the trophic levels of the food chain.Firmicutes and Proteobacteria were identi ed as the dominant host bacteria in the food chain system, which were more likely to be used as carriers of ARGs to promote the spread of resistance in the food chain.The results were used to evaluate the potential ecological risks of livestock and poultry manure and provide theoretical basis and scienti c support for the formulation of ARGs prevention and control policies.

Biosafety assessment of laying hens fed different treatments of black soldier flies (Hermetia illucens) under doxycycline stress

“…The trend of ARG/MGE gene abundance detected in the colon contents ( Figure 3D ), cloacal ( Figure 3E ) and eggshell samples ( Figure 3F ) of laying hens was similar to that in the BSF intestinal content samples. This indicated that ARGs/MGEs travel through the food chain ( Zhang et al, 2023 ). Notably, the food chain affects eggs, and the transfer of antibiotic resistance genes from food to humans has long been established ( Wang et al, 2012 ).…”