In recent years, it has been increasingly
recognized that soil
animals are hidden reservoirs of antibiotic resistance genes (ARGs)
and play a vital role in spreading ARGs in soil ecosystems. However,
little is known about the variation of ARGs among different animals
in the soil food web and effects of trophic levels and land uses on
them. We characterized the antibiotic resistomes of 495 soil animal
samples collected from six regions across China, including two different
land uses. A total of 265 ARGs were detected in all animal samples,
and relative abundances of ARGs in animals were significantly higher
than in soils. In addition, significant differences in ARGs were observed
among different animal groups. Twelve common ARGs were identified
among all animal groups, accounting for 17.4% of total ARGs abundance.
A positive and significant correlation was found between δ15N values (trophic level) and total ARGs abundance in animals.
The relative abundance of ARGs in the soil food web from arable land
was higher than forest land. Changes in soil antibiotics may indirectly
affect animal resistome by altering soil ARGs. This study suggests
that the risk of ARGs spreading through the food web is greater in
arable than in forest ecosystems.