All Diseases

Black Spot Disease

Black Spot Disease is caused by Vibrio anguillarum bacteria, which is capable of spreading in water. Shrimp infected by this disease have black spots and a brownish color on their shell. Poor water quality and excessive levels of organic feed residue at the pond bottom increase the risk of this disease.

Indication of Disease

Name

Black Spot Disease

Clinical signs

Brownish shell with black spots.

Method of diagnosis

Appearance of black spots on shrimp’s body which may occur post-harvest.

contoh-udang-yang-terkena-penyakit-black-spot-disease.jpg Source: American Aqua Viet Nam

Pathogen

Name

Vibrio anguillarum

Type of pathogen

Gram-negative bacteria

Synonyms

No information

Characteristics

This bacteria grows in saltwater at a temperature range of 25-32°C.

Pathogen Effect

Toxicity

As it occurs during the post-harvest stage, the appearance of black spots show a decrease in quality of fresh shrimp.

Predispositional factors

Poor water quality and a high amount of organic feed residues at the bottom of the pond can be major factors contributing to this disease. After harvest, shrimp exposed to sunlight may develop black spots.

Transmission

No data.

Epidemiology

Indonesia and other Asian countries.

Host or vector

This bacteria spreads through water.

Infectious dose

No data.

Incubation period

No data.

Stability and Viability

Susceptibility to drugs

No data.

Susceptibility to disinfectants/probiotics

No data.

Physical inactivation

After harvesting, shrimp should be frozen immediately and transported in cold chain distribution to inhibit the formation of black spots. Treatment with a solution of ascorbic acid or sodium bisulfite (NaHSO₃) in a cold saline solution can also help prevent black spots.

Handling and Prevention

Early warning

No data.

Prevention

Prevention of this disease can be done by cleaning the pond bottom of waste, feed residues, and molting remains, as well as maintaining good water quality.

Treatment

No data.

Eradication

No data.

Regulation and Other Information

No data.

References

Cipriani,G.R., Wheeler,R.S., and Sizemore,R.K. 1980. Characterization of brown spot disease of gulf coast shrimp. Journal of Invertebrate Pathology 36(2):255-263. Doi: 10.1016/0022-2011(80)90031-2

Flegel, T.W., D.F. Fegan, S. Kongsom, S. Vuthikomudomkit, S. Sriurairatana, S. Boonyaratpalin, C. Chantanachookhin, J.E. Vickers and O.D. Macdonald. 1992. Occurrence, diagnosis and treatment of shrimp diseases in Thailand. In: W. Fulks and K.L. Main (eds.). Diseases of Cultured Penaeid Shrimp in Asia and the United States. The Oceanic Institute: Honolulu. p. 57-112.

Ganjoor, M. 2015. A Short Review on Infectious Viruses in Cultural Shrimps (Penaeidae Family). Journal of Fisheries Science. 9 (3): 9-33.

Lotz, J.M. 1997. Special Topic Review: Viruses, Biosecurity and Specific Pathogen-free Stocks in Shrimp Aquaculture. World Journal of Microbiology & Biotechnology. 13: 406-413.