摘要
The diagnosis of bacterial fish diseases has progressed from traditional culture・dependent methods involving the recoveryof pathogens on agar-containing media and identification by examination of phenotypic traits. Newer approaches centreon culture-independent approaches. A problem with culturing is that it lacks sensitivity, tends to be slow, and its successdepends on the composition of the media and incubation conditions employed. In contrast, culture-independent methods,now centring on molecular methods, are highly specific and sensitive. This raises an important issue that detection of verylow numbers of bacterial cells does not necessarily imply the presence of clinical disease. Positivity could reflect backgroundpopulations of the pathogen that may be present in the aquatic environment.
