Tilapia fish is the second farmed fish in the world. One of the most important features of tilapia is its greater resistance to diseases comparing to the other farmed fish. However, it should be noted that many infectious pathogens can affect the tilapia fish, which may lead to serious problems and losses. It is necessary to pay attention to the investigation of diseases and the basic planning of its prevention and control.
Aquatic diseases have damaged tilapia aquaculture industry in different areas of the world. Tilapia aquaculture does not have a long history in Iran and planning for hygiene observations and preventing of disease prevalence must be considered.
Tilapia hatchery and indoor systems of National Research Center of Saline water Aquatics in central Iran were monitored for infectious disease. Unusual locomotion/ feeding or uncommon signs in the shape or body surface of cultured tilapias, fries and eggs or exceed mortalities were mentioned for bacterial, fungal, parasitic or viral pathogens. Infectious agents in this study were bacteria Streptococcus and Edwardsiella, the fungi Penicillium and Aspergillus and parasitic monogeneans Gyrodactylus and Dactylogyrus. No viral agent was diagnosed.
Although recorded pathogens were rarely observed during the study, but much attention must be paid for hygiene monitoring and instruction performance. Key aspects of aquatic health management of tilapia breeding systems are reducing exposure to pathogens and reducing stressors that predispose fish to pathogen contamination.