The management of fish health within a finfish aquaculture facility will vary according to the type of operation (hatchery/growout), location and species cultured.
In general however, disease management requires a holistic approach, inclusive of water quality management, hygiene, feed management, aeration, bird control, larval/fingerling health and broodstock husbandry.
Members of the finfish aquaculture industry must ensure that the risk of disease outbreak is minimised and that, in the event of a disease outbreak, the administering authority (QDPI&F) is informed and that the threat of disease spread within the facility or from the facility is minimised.
In order to manage fish health, aquaculturists must minimise stress in fish through appropriate pond and hatchery management. Stress levels in fish can be reduced through:
- Appropriate feed management
- Maintaining appropriate stocking densities
- Regular water quality maintenance
- Maintenance of appropriate levels of aeration
- Appropriate handling techniques
Ensuring tanks are free of excess sediment, faeces and algae.
In order for pathogens and parasites to establish in an aquaculture facility there needs to be an introduction of the causative organism. Principally these organisms are introduced from sources such as:
- Broodstock
- Uncontrolled human contact
- Birds and other predators
- Incoming water
- Vector hosts
- LIVE FOOD
Accordingly there is a need for finfish aquaculturists to appropriately manage these potential entry points. Management of pathogen and parasite entry points may include:
- Screening broodstock for known pathogens and parasites
- Maintaining broodstock in a quarantine area for a suitable period
- Appropriate approved chemical treatment of broodstock prior to entry into the general hatchery population
- Installation and use of foot baths and hand washing facilities
- Restrictions on vehicles around ponds
- Provision of quarantined footwear to visitors
- Appropriately managing bird and predator populations around ponds
- Screening or treating water prior to use in tanks or ponds
Minimising or where possible eliminating the potential for vector hosts to enter the aquaculture system.
It is possible for translocation of pathogens and parasites to occur through the release of fingerlings or fish. Where aquaculturists intend to supply or produce fish for release into natural populations, one or more of the following practices must be adopted:
- Appropriate approved chemical treatment of fingerlings/fish prior to release
- Random inspection of fingerlings/fish prior to release
- Random pathological inspections prior to release of fingerlings/fish
- Disease testing by DPI or other diagnostic service
It is not always possible to eliminate diseases from an aquaculture facility entirely.
Finfish aquaculturists must notify a Fisheries Research Centre or a Fisheries Extension officer or the Queensland Boating and Fisheries Patrol (QBFP) if they reasonably suspect or know of a disease outbreak.
In the event of a disease/parasite outbreak or suspected outbreak the aquaculturists must ensure that the threat of disease spread within the facility or to outside of the facility is minimised.
- In order to appropriately manage disease outbreaks aquaculturists must
- Notify the Administering Authority (QDPI&F) of all disease outbreaks in fisheries resources
- Not cause the release of diseased fingerlings/fish into the wild
- Not sell diseased fish
- Appropriately quarantine affected ponds/tanks
- Collect sick specimens of affected aquatic animals for laboratory examination where appropriate/requested
Dispose of carcasses by burial or in accordance with the recommendations of the Administering Authority.
Information Prepared By:
Dallas J Donovan
Information Sourced From:
