(5) Status of occurrence of fish diseases and use of fishery medicines, etc.

○ In marine fish aquaculture, such diseases as streptococcinosis and pseudotuberculosis became widespread in the past. Today, vaccines for major diseases of each fish species have become available, so the occurrence of fish diseases and use of antibiotics decreased dramatically.

○ In order to ensure that fishery medicines will not remain in food, the Pharmaceutical Affairs Act regulates the use of medicines other than those approved by the national government and, with regard to antibacterial fishery medicines and vermiñuges, specifies the types of aquatic animals for which they can be used, their dosage and administration, and the required interval period between the end of their use and harvest, and obligates compliance with these specifications. To ensure proper use of medicines, including vaccines, a framework has been established whereby the fisheries experimental station, etc. of each prefecture instructs methods of use and other matters concerning medicines to aquaculture operators.

○ Import of foreign seeds that may hold pathogens that do not exist around Japan is regulated for some fish species under the Act on the Protection of Fishery Resources.

[Changes in the fish disease damage to feeding aquacultured fish]

Source: Fisheries Agency survey

[Changes in the number of vaccinated fish, the fish disease damage, and the value of antibiotics used for yellowtails in

## [Column: Aquatic animal vaccines]

O Vaccines prevent diseases by introducing pathogens with no or weakened infectious capacity into the body and making the body acquire immunity against the pathogens. At present, all fishery vaccines used are inactivated vaccines with no infectious capacity.

O The safety of vaccines has been confirmed through various systems including the national government's approval and inspections under the Pharmaceutical Affairs Act.

O The main method used for vaccination is injection, which uses only a small amount of vaccine and is considered to be capable of securely administering the predetermined amount.

Yellowtail juveniles are vaccinated by injection about one month after being moved into a fish pen.

Photos courtesy of the Kumamoto Seawater Culture Fisheries Cooperative Association.

## Section 3: Aquaculture products and dining table

(1) New efforts to sell cultured fish(Efforts to ensure safety and stable quality)
○ In order to analyze the production processes of cultured fish and take measures to avoid any risk factors in advance in the process of aquaculture production so as to ensure the safety of fishery products, it is important to prepare and implement a good aquaculture practice (GAP) that suits the actual conditions of the production area.
○ There are producers who not only aim at stable-quality aquaculture production by formulating a manual for quality control, but also make voluntary efforts to secure consumer confidence by disclosing the production history.
(Quality improvement and branding of aquaculture products)
○ Due to advancement of feed and other factors, the fatty smell, which had been considered characteristic to cultured fish, has been successfully controlled to a considerable extent today.
○ Cultured fish tend to have higher content of n-3 polyunsaturated fatty acids (DHA, EPA, etc.) than wild fish.
○ Since aquaculture is suitable for controlling production and securing stable quality, it is relatively easy to create branded cultured fish. Recently, cultured fish for which fat deterioration is prevented and fishy odor is restrained by mixing citrus fruits, etc. in the feed has gained popularity as “citrus-fed fish.”
○ It is necessary to establish production management for maintaining stable quality and the labeling for indicating the brand.