The application of extensive
practices in the farming of aquatic animals has led to problems.
Because aquatic products can easily become infected due to large
stocking densities; to avoid disease and reduce losses, antibiotic
overuse frequently occurs in artificial breeding (Zheng et al.,2012).
Most oyster farms are near estuaries, such as Hai-ling Bay, and
these water bodies are closely linked to polluted residential areas.
All of these factors may lead to bacterial resistance. Thus, a total of
1,050 heterotrophic bacteria were isolated from oysters (582
strains) and farming seawater (468 strains) in this area.