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Daily Check List

Weekly Check List

Monthly Monitoring

Feed Requirements

Essential Nutrients

Additional Nutritional Factors

Feeding Regime

Water Quality Requirements

Water Quality Action and Reaction

Water Quality Management and Biofilter Maintenance

Post larval fitness parameters

Post Larva Acclimitation


Risk Management, Bio-security and HACCP Implementation


System Disinfection Procedures

Equipment Maintenance

Record Keeping and Report Templates


Epicommensal fouling disease. Filamentous bacterial disease. Ectocommensal protozoa.

Several kinds of protozoa are regularly found on surfaces, including gills, of shrimp. Apparently, shrimp surfaces are a favored place to live within the water environment. Common on the surfaces of shrimp arespecies of Zoothamnium, Epistylis, Acineta, Ephelota, and Lagenophrys

Zoothamnium is a frequent inhabitant of the gill surfaces of shrimp, and in ponds with low oxygen content, heavily infested shrimp can suffocate. Surface-settling protozoa occasionally cause problems in shrimp hatcheries when larval shrimp become overburdened and are unable to swim normally. As protozoa continuously multiply in numbers, shrimp acquire an increasing burden until shedding of the cuticle provides relief.

Members of one unique group of protozoa, the apostome ciliates, have a resting stage that will settle on shrimp surfaces. When the crustacean molts, the protozoan releases and completes the life cycle within the shed cuticle before entering a resting stage on a new crustacean.

Shrimp infected by epicommensals are characterized by rough body surfaces, gill diseases or both. Protozoan epicommensals have not been observed growing internally in the gills or in other tissues but, when abundant on the body surfaces, appendages or gills, can cause difficulties in locomotion, feeding, molting, and respiration, resulting in mortalities. In cultured P. monodon diseases in southern Taiwan one found that the rate of epicommensal infection was 6. 9% , with the infection rate of Zoothamnium sp. at 80% .When this species attaches to P . monodon, the prawn turns blackishbrown and its body surfaces become fouled, movement is impaired, activity is reduced and, in serious cases, heavy mortalities result

Methods of Control and Treatment:

Culture environment have to improved before chemical treament is used. If the infection is not serious, the water is replaced for stimulating shrimp to molt. After the shrimp have molted, the water is changed again one or twice. Formalin can also be used. Adult shrimp are treated with a 25 -30 ppm bath for one day, larvae are given a 15-ppm bath for one day and juveniles receive 15 -20 ppm for 10 -12 h. Shrimp are not fed during Formalin treatment and the water is drained after 24 h to remove any traces of the chemical. After treating with Formalin for one or two days, benzalkonium chloride (BKC) can be applied at a rate of 0.5 1.0 ppm for one day to prevent secondary infection.




Variables to be used in health evaluation

Health evaluation tests
Wet Mount Procedure . PL visual examination . Stress test for post larva . Gill examination . Mid-gut Examination . Stomach Contents Analysis

Shrimp Diseases
Hepatopancreatic parvo-like virus (HPV) . Reo-like virus (REO) . Lymphoid organ vacuolization virus (LOVV) . Taura Syndrome Virus (TSV) . Rhabdovirus of Penaeid Shrimp (RPS) . White Spot Syndrome Virus (WSSV) . Infectious hypodermal and hematopoietic virus (IHHNV) . Baculovirus penaei (BP)
Bacterial Diseases
Vibriosis . You are here . Necrotizing Hepatopancreatitis (NHP) . Black spot disease (BSD) . Mycobacteriosis
Fungal Diseases
Larval mycosis . Fusariosis
Haplosporidia . Gregarines . Cotton Disease
Black Gill Disease (BGD) Dissolved Oxygen Crisis Nitrogen Gas Bubble Disease

Disease control
Decreasing density, partial or early harvests . Drugs, chemicals and treatments . Sanitation