1. Fish Health/Disease Mortality in Aquaculture Disease
Contributing Factors
Natural mortality: Broodstock – age related
Disease
Viruses, Fungi, Bacteria and Parasites
Infection vs. Disease
Most are stress-mediated
Disease transmission
Though water –
Through egg/adults –

2. Fish Health/Disease Mortality in Aquaculture
Preventative measures (Bio-security)
Proper management
Early diagnosis of disease – treat early
Sanitation
Vaccination
Treatment
Isolation and Environmental Manipulation

3. Fish Health/Disease Proper management Observation of fish
Signs of stress
Unusual behavior
Skin lesions
Secondary infections
Due to stress
Ex: Channel catfish in recirculation system
Average wt: 1 kg
Density: 600 g/l
Healthy condition
Power failure occurred
Resulted in: -
- Costia epizootic several days later
Treatment with:
Disease + treatment = stress = additional disease due to other pathogens 1 week later = all fish died due to secondary infections.

4. Fish Health/Disease Proper management Vaccines Sanitation
Disinfection of all equipment, tanks, people, etc.
Restrictions on visitors
Disinfect boots, waders, etc.
Vaccines
Injection
Immersion/spray
Oral (feed)
Ongoing research and development
Viral and bacterial diseases

5. Fish Health/Disease Treatment Isolation Physical environment
Isolate affected animals or groups
Avoid contamination with uninfected groups
Physical environment
Disease treatments
Temperature or salinity changes
Re-circulation systems
Ponds
Difficult to treat