1. DISEASE & PEST MANAGEMENT [objectives]
Explain aquaculture diseases and pests and how they cause problems
Discuss how fish show signs of disease
Explain diseases and how they are managed
Explain parasites and how they are managed
Explain predators and how they are managed
Describe trash fish and the problems they cause
Explain what to do if fish appear unhealthy
Discuss regulations in disease and pest control

2. AQUACULTURE DISEASES AND PESTS – chapter 6
A disease is a condition that develops in an organism and then damages it in some way.
A pest is a plant, animal, or other organism that is detrimental to a species.
Aquacrops need a healthy environment; one that is free from diseases and pests.
Diseases and pests cause losses.

3. EXAMPLES

4. KINDS OF LOSSES
Direct losses occur when aquacrop is attacked or injured.
Water birds and predators (eat crop)
Diseases (reduce growth or death)
Parasites (reduce growth, produce stress)
Poaching (theft by humans)

5. KINDS OF LOSSES
Indirect losses result in less than ideal environments.
Weeds (make harvesting difficult)
Trash fish (compete for food and oxygen)
Rodents or other burrowing animals (may cause water leaks)

6. SIGNS OF DISEASE IN FISH (SYMPTOMS)
Not eating (going off the feed)
Skin abnormalities (ulcers, lesions, abscesses)
Lack of vigor (sluggish, drooping fins)
Abnormal body shape (growths, swollen belly, bulging eyes)
Behavioral change (rubbing, gulping)
Dead fish

8. KINDS OF DISEASES
Infectious diseases – may be transferred from one individual to another (examples – bacterial infections, fungal and viral diseases, parasite infestations)
Noninfectious diseases – not transferred from one individual to another (examples – nutritional, environmental, chemical and physiological disease)

9. INFECTIOUS DISEASES
Fungal
Bacterial
Parasitic fish lice
Viral

10. NONINFECTIOUS DISEASES
Nutritional diseases – inadequate diet
Environmental diseases – water gases, improper temperatures and water quality
Chemical diseases – contaminants such as pesticides or heavy metals
Physiological diseases – organ malfunctions from sudden changes

11. DISEASE CONTROL
Prevention – the practice of keeping aquacrops healthy and disease free
Sanitation – practice of keeping water and facilities clean
Quarantine – isolation of aquacrops not known to be disease free from those that are

12. DISEASE TREATMENT Dipping – immersing fish in concentrated medication
Feeding – using medicated feed
Bathing – similar to dipping but less concentrated for longer period of time
Injecting – only for fish large enough to hold
Indefinite treatment – low dose of medication added to tank or pond

13. PARASITES AND THEIR CONTROL
Ectoparasites (external) – found on skin, gills, or fins
Endoparasites (internal) – live in organs, flesh, or digestive tract
Examples – tapeworms, flukes, leeches, roundworms, protozoans, crustaceans.

14. PARASITE CONTROL Quarantine - isolation
Treatment of facilities – dry ponds and sterilize
Dipping – salt solution, formalin
Bird elimination – birds often transfer parasites
Indefinite treatment

15. PREDATORS AND THEIR CONTROL
Birds – cormorants, kingfishers, herons, grebes, and mergansers
Fish – some prey on other fish, some prey on eggs
Snakes – do not eat large amount of fish
Insects – can destroy eggs or fry
Turtles and alligators – usually only eat trash fish (gars, carp)
Bullfrogs – eat fingerlings (crawfish, too!)

16. BIRDS

17. FISH, SNAKES,INSECTS, BULLFROGS