|Fishes also suffer from disease and parasites like humans. They show both specific and non-specific defence. These diseases can be due to bacterial fungal and mould infections. And also due to Undesirable environmental conditions such as water quality, overcrowding, stress by incompatible species etc. Diagnosis of fish diseases depends on Physical/Behavioral signs or symptoms of fish.The top open access journals are peer reviewed scholarly journals of [Journal of Marine Science: Research & Development]. The top open access journals are freely available on the public internet domain, allowing any end users to read, download, copy, distribute, prink, search or link to the full texts of the articles. These provide high quality, meticulously reviewed and rapid publication, to cater the insistent need of scientific community. These journals are indexed with all their citations noted. The top open access journals are indexed in SCOPUS, COPERNICUS, CAS, EBSCO and ISI.