Write an account of Tiger Prawn culture with emphasis on seed resources and transportation. (IFS 2021/10 Marks)

Introduction

Tiger prawn culture, also known as Penaeus monodon culture, is an important aspect of aquaculture that involves the farming of these large and commercially valuable prawns. The availability of high-quality seed resources and efficient transportation methods play a crucial role in ensuring the success of the culture. 

Tiger Prawn Culture

• Habitat Requirements for Culture
  
  • Tiger prawns thrive in tropical and subtropical coastal areas with brackish water.
  • Optimal water salinity is between 10-25 ppt, and a temperature range of 28-33°C.
  • Example: Coastal ponds and estuarine areas are typically modified for prawn culture.
• Feeding and Nutrition
  
  • Prawns are fed with formulated diets rich in protein, vitamins, and minerals.
  • Proper feeding enhances growth rate and survival rate, improving yield.
  • Example: Commercial feed pellets or organic materials like small fish and shrimp.
• Water Quality Management
  
  • Maintaining water quality is crucial to prevent diseases and ensure healthy growth.
  • Parameters like dissolved oxygen, pH, and ammonia levels are regularly monitored.
  • Example: Aerators are used in ponds to maintain oxygen levels for prawn health.
• Disease Control and Prevention
  
  • Disease outbreaks, such as white spot disease, are a major challenge in prawn culture.
  • Preventive measures include quarantine, regular pond cleaning, and vaccination.
  • Example: Use of probiotics and biosecurity measures to minimize pathogen spread.
• Harvesting Techniques
  
  • Harvesting typically occurs when prawns reach a marketable size, around 120-150 days.
  • Techniques include netting, draining ponds, or using traps.
  • Example: In India, prawn ponds are drained, and prawns are manually collected.
• Economic Importance
  
  • Tiger prawns have significant export value, contributing to the economy of coastal regions.
  • High demand in international markets leads to foreign exchange earnings.
  • Example: India is a major exporter of tiger prawns to the U.S. and European markets.
• Environmental Impact and Sustainable Practices
  
  • Intensive prawn culture can lead to water pollution and habitat destruction.
  • Sustainable practices, like polyculture and integrated farming, help reduce impact.
  • Example: Combining prawn farming with rice cultivation to minimize environmental impact.

Seed Resources for Tiger Prawn Culture

• Seed Source Identification
  
  • Seeds or post-larvae (PL) of tiger prawns are either collected from the wild or produced in hatcheries.
  • Wild seed collection is becoming less common due to environmental concerns.
  • Example: Hatchery-produced seeds are preferred for sustainable prawn farming.
• Hatchery Techniques for Seed Production
  
  • Hatcheries provide controlled environments for breeding and larval rearing of tiger prawns.
  • Techniques include broodstock conditioning, spawning, and larval rearing.
  • Example: India has developed numerous hatcheries along its coast for prawn seed production.
• Broodstock Management
  
  • Healthy and genetically diverse broodstock are essential for quality seed production.
  • Proper broodstock management ensures high hatching rates and survival of larvae.
  • Example: Selective breeding programs to enhance growth and disease resistance.
• Larval Stages and Growth
  
  • The larval stages include nauplius, zoea, mysis, and post-larvae stages.
  • Larvae require different diets and conditions at each stage for successful development.
  • Example: Live feed such as algae and Artemia are provided in the early stages.
• Nutrition and Feeding in Hatcheries
  
  • Proper feeding is crucial during the larval stages to produce healthy post-larvae.
  • Common feeds include microalgae, rotifers, and specially formulated larval feeds.
  • Example: Microalgae like Chaetoceros and Tetraselmis are commonly used as live feed.
• Quality Control and Seed Selection
  
  • Only healthy, uniform-sized post-larvae are selected for stocking in grow-out ponds.
  • Quality control measures help ensure high survival rates in grow-out phases.
  • Example: Visual inspection and health checks for deformities or disease symptoms.
• Stocking Density
  
  • Proper stocking density prevents overcrowding and reduces disease risk.
  • Ideal stocking densities vary depending on the size of the pond and water quality.
  • Example: For extensive systems, densities are lower than in semi-intensive or intensive systems.
• Conservation of Wild Prawn Populations
  
  • Reliance on wild-caught seeds can deplete natural prawn populations.
  • Hatchery production helps reduce this pressure on wild stocks.
  • Example: Policies and guidelines in place to protect wild prawn habitats.

Transportation of Seed Resources

• Importance of Proper Transport
  
  • Safe transport of prawn seed ensures high survival rates upon reaching grow-out facilities.
  • Proper handling during transportation minimizes stress and mortality.
  • Example: Transported from hatcheries to farms over short or long distances.
• Methods of Seed Transport
  
  • Seeds are transported in oxygenated bags or specially designed containers.
  • Both waterless and water-based transport methods are used based on distance.
  • Example: For long distances, insulated containers with oxygen supply are used.
• Packaging Techniques
  
  • Seeds are packed in plastic bags with water and oxygen to maintain freshness.
  • Bagged transport allows for easy handling and temperature control.
  • Example: Seeds are packed with a ratio of oxygen to water for optimal survival.
• Temperature Control During Transport
  
  • Temperature control reduces stress on prawn seeds and improves survival rates.
  • Cold packs or temperature-regulated containers are often used.
  • Example: Seeds transported in cool boxes for long distances in tropical regions.
• Minimizing Transport Stress
  
  • Reducing handling and maintaining stable conditions help minimize stress.
  • Anti-stress agents or conditioners are sometimes added to transport water.
  • Example: Salt or sodium chloride is added to water to reduce stress in transported larvae.
• Monitoring Oxygen Levels
  
  • High oxygen levels are maintained to ensure seeds have adequate respiration.
  • Frequent monitoring and adjustment of oxygen levels during transport.
  • Example: Oxygenated bags allow for up to 24 hours of safe transport.
• Ensuring Seed Quality Post-Transport
  
  • Upon arrival, seeds are acclimated to pond conditions to reduce shock.
  • Seeds are gradually introduced to the pond environment for better survival.
  • Example: Acclimation involves gradually mixing pond water with transport water.
• Challenges in Seed Transportation
  
  • Long-distance transport poses risks due to temperature changes and handling.
  • High mortality rates may occur if transportation conditions are not optimal.
  • Example: Seasonal temperature fluctuations can impact prawn seed survival.

Conclusion

Tiger Prawn culture is a significant aspect of aquaculture that requires careful attention to seed resources and transportation. High-quality seed resources and efficient transportation methods are essential for the success of Tiger Prawn culture.