Shrimp MBV Diagnosis Protocol

1. Pathogen Overview

The Monodon Baculovirus (MBV) is a viral disease affecting the giant tiger shrimp (Penaeus monodon), leading to slow growth, increased mortality rates, and severe impacts on the aquaculture industry.

2. Clinical Symptoms Observation

• Darkening of shrimp's body color and reduced activity.
• Necrosis in antennas and appendages.
• Uneven body size and shape among shrimp.
• Gradual increase in mortality rates, especially in juveniles.

3. Sample Collection

• Randomly select a minimum of 30 suspected infected shrimp from the pond as samples.
• Avoid cross-contamination during collection using sterile tools.
• Samples should include shrimp of different sizes to cover various infection stages.

4. Laboratory Testing

4.1 Histopathological Examination

• Take slices of shrimp organs like hepatopancreas and muscles.
• Use a microscope to observe the presence of typical baculovirus inclusion bodies.

4.2 PCR Testing

• Extract DNA from shrimp tissues.
• Design specific primers to amplify MBV gene segments.
• Confirm the presence of MBV DNA through gel electrophoresis or real-time PCR.

4.3 Electron Microscopy Observation

Prepare ultrathin sections and observe virus particle morphology using transmission electron microscopy.

5. Results Analysis and Reporting

• Evaluate results from clinical symptoms, histopathological examination, PCR testing, and electron microscopy to make an integrated assessment.
• Provide a detailed diagnostic report, including testing methods, result interpretation, and recommended measures.

6. Prevention and Control Recommendations

• Enhance water quality management in aquaculture ponds and conduct regular disinfection.
• Implement strict quarantine measures to prevent pathogen entry.
• Isolate diseased shrimp immediately upon an outbreak to minimize losses.
• Promote healthy farming practices and biosecurity measures.
• Adjust the above protocol according to specific circumstances and comply with local laws and ethical standards during implementation. Furthermore, due to continuous advancements in science and technology, it is advisable to regularly update diagnostic methods and equipment to ensure the accuracy and effectiveness of diagnosis.