Taura Syndrome – Signs, Prevention, and Disease Control

Like white spot disease (WSSV) and yellow head disease (YHV), red tail disease, or Taura Syndrome, is one of the dangerous diseases threatening the shrimp farming industry, especially in intensive, high-density ponds. Let Vemedim help you learn about the causes, signs, and how to prevent and control it in time to reduce the risk of mass mortality, which seriously affects the economic efficiency of shrimp farmers.

The causative agent of Taura Syndrome in shrimp

Red tail disease in shrimp, also known as Taura syndrome (TSV), is one of the serious diseases that directly threatens the efficiency of whiteleg shrimp farming. This disease mainly appears in intensive, high-density ponds and often attacks shrimp at 14–45 days of age. If not detected and controlled in time, TSV can cause mass shrimp mortality, seriously affecting productivity and profit.

*Red tail disease in shrimp, or Taura syndrome (TSV), is a serious disease that greatly affects the productivity and profit of shrimp farmers*

Taura syndrome is caused by TSV virus. Initially, this virus was classified in the family Picornaviridae, but in 2005 it was reclassified into the family Dicistroviridae. The virus is spherical, about 32 nm in diameter, has an RNA core structure, and mainly parasitizes the epithelial cells of shrimp.

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Symptoms of Taura Syndrome in shrimp

Shrimp infected with TSV show signs similar to some other diseases, such as reduced feeding, soft shell, sluggish swimming, and gathering near the pond edges. However, Taura syndrome has characteristic manifestations in each stage:

Acute stage

This is the most dangerous stage, with the highest mortality rate, usually occurring 2–7 days after shrimp are infected with the virus:

Body color change: Shrimp turn pale red, most clearly on the tail and appendages such as swimming legs and walking legs. This is why the disease is also called “red tail shrimp.”
Localized necrosis: The edges of the swimming legs, walking legs, and tail are often swollen, thickened, and show mild necrosis.
Soft shell, empty gut: Shrimp have difficulty molting, the shell becomes soft, and the gut shrinks or even becomes empty. When molting, shrimp often die immediately.
Abnormal behavior: Shrimp swim sluggishly, move little, are easily pushed to the pond edges, eat less, or stop eating completely.

At this stage, if not intervened in time, the mortality rate in shrimp affected by Taura Syndrome can reach 40–90%, causing very large economic losses.

*Taura syndrome is caused by TSV virus with an RNA core structure*

Transition stage

Shrimp that survive the acute stage will enter the transition stage, during which the virus is still present but the shrimp begin to mount an immune response:

More normal feeding and movement: Some shrimp may start feeding again, but they are still weaker than healthy shrimp.
Soft shell and slight discoloration: Some individuals may have a soft shell or pale red coloration on the tail and legs, but not uniformly.
Brown and black spots appear: Small brown or black spots appear on the chitin shell, resulting from the shrimp’s immune response against the virus. These spots are not limited to the tail but may spread to the walking legs, swimming legs, and body.
Reduced growth rate: Shrimp grow more slowly than normal because energy is mainly directed toward immune responses rather than growth.

This stage can last 5–10 days depending on environmental conditions and the level of viral infection.

Chronic stage

Some shrimp that survive the previous two stages will enter the chronic stage, when the virus is still present but its impact on the body has decreased:

More black spots on the shell: The chitin shell develops more black or dark brown spots than in the transition stage, mainly on the appendages and tail.
Near-normal morphology: After several molts, shrimp begin to return to normal color and structure, although they still carry the virus in their bodies.
Growth and reproduction ability: Chronic shrimp can continue to grow, but at an uneven rate. TSV does not cause immediate death but can be transmitted to offspring if broodstock carry the Taura Syndrome pathogen.

*Taura syndrome causes shrimp bodies to turn pale red, especially the swimming legs, walking legs, and tail, which often become swollen and thickened*

Prevention and handling of Taura Syndrome

Because TSV is a virus, there is currently no specific treatment. Therefore, comprehensive prevention is the most important solution:

Prepare the pond cleanly, limiting the entry of crustaceans carrying pathogens.
Filter and treat water thoroughly before supplying it to the pond.
Use disease-free postlarvae with PCR certification negative for TSV.
Feed shrimp a nutritious diet, supplementing vitamins and minerals with Anti Shock or Herbal Pro to boost resistance.
Use probiotics to support the pond environment, such as Vemedim Bitech Yucca and Vemedim Aqua Bacillus to decompose organic sludge, limit harmful microorganisms, and improve water quality.
Monitor the pond regularly to detect abnormal signs early.

When shrimp suspected of Taura Syndrome are detected, the water environment must be treated immediately, pH should be raised above 8 in the morning, and feed rations adjusted to reduce shrimp molting. Depending on the severity of the disease, farmers may harvest early or manage the virus until harvest time to limit economic losses.

*Keeping the farming environment clean, choosing healthy postlarvae, and closely monitoring the pond are effective ways to prevent Taura Syndrome*

Taura Syndrome (TSV) is not merely a minor concern but a formidable “enemy” in shrimp farming. Proactively applying biosecurity measures, tightly managing the pond, and selecting disease-free seed are the keys to minimizing risks. With support from Vemedim, shrimp farmers can improve disease prevention, protect their shrimp stock, and aim for a stable, successful crop. For more details on suitable solutions, please contact Vemedim for advice!