Fisheries play a great role in food security and livelihood and are a source of income and social development in developing countries. Recently the sector attracted great attention and it is growing rapidly through the development of aquaculture. New technological advances and increased demands for fish as a source of animal protein are themain reasons for the industry’s growth. Because of expansion of the industry, the culture methods have become more intensive for producing higher yields.
Aquaculture production of fish makes up forty-four percent of total fish production in 2014 which is 74 million tons of fish worth of 160 billion dollars. Almost all fish produced from aquaculture is for human consumption.
Huge loss of production in aquaculture is occurring because ofmany reasons. Among these causes, a disease is the most serious constraint that causes damage to the livelihood of farmers, loss of job, reduced incomes, and food insecurity.
Studies showed that almost fifty percent of production loss is because of diseases which are more severe in developing countries. This is because ninety percent of the aquaculture firm is in the developing world. The annual loss of revenues because of disease reaches up to 6 billion dollars. For instance, in Chile, infectious salmon anemia alone costs 2 billion dollars and caused 20000 workers to lose their jobs. In China, one of the leading countries in aquaculture production has a loss of 15 percent of the total fish production to diseases.
To overcome losses because of infectious diseases in aquaculture, it is necessary to act upon every health constraint based on scientifically proven and recommended as well as locally applicable ways. Challenges in aquaculture because of climate change, limited water sources, and the growth drive the need for epidemiological approaches in keeping aquatic animal health safe. As “prevention is better than treatment,” it is advisable to focus on preventing the occurrence of disease rather than treating it. The uses of improved husbandry/management practices, movement restrictions, genetically resistant stock, dietary supplements, nonspecific immunostimulants, vaccine, probiotics prebiotics, medicinal plant products, water disinfection biological control, antimicrobial compounds, water disinfection, and control of movement are the best approaches in control of infectious diseases of fish.
The use of antibiotics is under strict control and regulatory measures because of drug resistance and residue related issues. In response to reduced antibiotic use in fish, production vaccines have been playing a key role in infectious disease control in aquaculture for decades.
Vaccines get wide acceptance for the fact there is no risk of drug resistance development in vaccinated animals and protection of minority unvaccinated animals because of herd immunity.
A single approach to prevention and control of aquaculture health is not successful alone. Rather a combination of different strategies is effective. Setting up a national or regional information exchange between farmers and responsible parties is compulsory. Besides applying all these strategies, surveillance for diseases and having sensitive and specific diagnostic tests are invaluable to assure healthy fish.
Source : Veterinary Medicine International, Volume 2018, Article ID 5432497, 10 pages.