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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


Mycobacteriosis, Shrimp tuberculosis.

Scientific name or taxonomic affiliation

Mycobacterium marinum, Mycobacterium fortuitum, and Mycobacterium sp.

Geographic distribution


Host species

Potentially infectious to all penaeids.

Impact on the host

Infected shrimp produce unsightly melanized nodules or lesions on the shell or in the muscle that pose more of a problem to marketing than to losses due to mortalities. Also, these bacteria have been reported to cause accidental infections in the hands of shrimp farm or packing plant workers that resulted in nodular skin lesions that were difficult to treat.

Diagnostic techniques

Gross Observations: Multifocal melanized areas in the tissues (muscle, ovary, heart, gills, etc.) or large raised irregular melanized lesions in or on the cuticle.

Smears: Demonstration of Gram positive, acid-fast (by Zeihl-Neelsen stain or related methods), rod-shaped bacteria in impression smears from melanized lesions.

Histology: The presence of acid-fast, Gram positive, rod-shaped bacteria in the melanized lesions is required to make a diagnosis to the genus Mycobacterium. The lesions consist of multifocal, usually heavily melanized, haemocytic nodules or larger granulomatous lesions. With haematoxylin and eosin stain, palely basophilic rod-shaped bacteria may be evident in, or associated with the haemocytic nodules.

Culture: Isolation of an acid-fast bacterium on special media for Mycobacterium spp.

Methods of Control

No known method of prevention or control.




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 . Epicommensal fouling disease (filementous bacteria) . Necrotizing Hepatopancreatitis (NHP) . Black spot disease (BSD) . You are here
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