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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


Vibriosis or bacterial disease, Penaeid bacterial septicemia, Penaeid vibriosis, Luminescent vibriosis, Red-leg disease, "sien dun" in Thai which translates to black splint, Sea gull syndrome or "Sindroma de gaviota" in Latin America.

Scientific name or taxonomic affiliation
Vibrio spp. (i.e., V. harveyi, V. vulnificus, V. anguillarum, V. splendidus, V. alginolyticus, V. nereis, V. parahaemolyticus, V. damsela, V. tubiashi, V. fluvialis). Other Gram negative, oxidase positive bacteria (i.e. Psuedomonas sp., Aeromonas sp. and Flavobacterium sp.) have also been isolated from shrimp with Vibrio sp. infections.

Geographic distribution

Host species
All cultured penaeids and cultured Macrobrachium rosenbergii are susceptible under stressful conditions.

Impact on the host
Anorexia and behavioural changes. Some species and strains of Vibrio cause the shrimp to be luminescent. Mortality ranges from insignificant to 100%, particularly in postlarvae and young juvenile shrimp. There is also concern over the appearance of antibiotic-resistant strains as reported for V. harveyi that cause mass mortality of cultured shrimp.

Diagnostic techniques
Gross Observations: Vary with the type of infection - black or brown cuticular lesions, opacity of musculature, tough and black branching filaments (up to 2 mm wide) in connective tissue of tail segments, black lymphoid (Oka) organ, melanization of appendage tips.

Wet Mounts: Large numbers of bacteria in the heamolymph.

Histology: Significant necrosis and inflammation especially in the Oka/lymphoid organ and frequently, but usually less severe, in the gills, heart, hepatopancreas and sometimes other tissues. Often there are rod shaped bacteria (usually slightly curved) within the tissues.

Culture: Isolate Vibrio spp. from tissue or haemolymph of moribund samples. The bacteria are not fastidious and will grow on a wide variety of nutrient agar media including the selective media Thiosulfate Citrate Bile Salts Agar (Lightner 1983). Detailed procedures and culture characteristics of several species of Vibrio were described by Lightner (1996).

Methods of Control
Maintain adequate water quality with low bacterial biomass, a stable phytoplankton bloom and a proper feeding program. Sterilize or filter recirculated water. Routinely monitor shrimp and pond for early diagnosis of a problem. Avoid temperature extremes or rapid variation in temperature, handling, overcrowding, and other stressors. Infections opportunistic and probably result from poor husbandry; may be secondary to other disease processes. In Thailand (and probably at other locations) the incidence of antibiotic resistance in the isolated strains was high.



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
You are here . Epicommensal fouling disease (filementous bacteria) . 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