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Understanding PL stages

Post-larval (PL) stages represent critical development phases in Vannamei shrimp production. Each stage exhibits distinct characteristics in size, appearance, and physiological development that determine suitability for different farming conditions.

Selecting the appropriate PL stage depends on farm infrastructure, water quality management capabilities, and operational experience. Our technical team provides guidance on stage selection based on specific farming conditions.

How a larva becomes seed

Between hatching and stocking, a Vannamei larva passes through four stages and twelve moults. Hatcheries name each one, and the name tells you what the larva eats and how it behaves.

  1. N1–N6

    Nauplius

    Duration
    About 2 days
    Feeding
    Does not feed; lives on its yolk

    Six moults in quick succession. The larva is a swimming dot with three pairs of appendages.

  2. Z1–Z3

    Zoea

    Duration
    About 3–4 days
    Feeding
    Filter-feeds on microalgae

    First feeding stage and the most delicate. Trailing faecal strands are a sign it is feeding well.

  3. M1–M3

    Mysis

    Duration
    About 3 days
    Feeding
    Algae, then live Artemia

    Now shrimp-shaped, swimming head-down with a flicking tail. Pleopods develop through the three moults.

  4. PL1 →

    Post-larva

    Duration
    Counted in days
    Feeding
    Artemia and formulated feed

    Swims forward like an adult. PL10 means ten days after this metamorphosis. This is the seed farms stock.

    What we supply

Drawings are schematic and not to scale with one another. Durations are typical at warm hatchery temperatures.

PL stage specifications

PL8

8 Days Post-Larval

For nursery systems run by experienced operators.

PL8 drawn to scale on a millimetre ruler: 6 to 7 mm average length. 0510 mm

Characteristics

  • Size: 6-7 mm average length
  • Age: 8 days post-metamorphosis
  • Appearance: Transparent body, visible digestive tract, active swimming behavior

Suitability

  • Farming Conditions: Nursery systems with controlled water quality and feeding protocols
  • Recommended For: Experienced operators with nursery infrastructure and technical monitoring capabilities

Quality indicators

  • Uniform size distribution within batch
  • Active swimming and feeding response
  • Clear body with no visible abnormalities
  • Negative PCR test results for major pathogens

Handling guidelines

  • Gradual acclimatization to farm water parameters over 30-45 minutes
  • Maintain oxygen levels during transport and stocking
  • Stock during cooler hours to minimize temperature stress
  • Implement immediate feeding protocol post-stocking

PL10

10 Days Post-Larval

For nurseries or well-prepared grow-out ponds with stable water.

PL10 drawn to scale on a millimetre ruler: 7 to 8 mm average length. 0510 mm

Characteristics

  • Size: 7-8 mm average length
  • Age: 10 days post-metamorphosis
  • Appearance: Developing pigmentation, stronger swimming patterns, increased activity

Suitability

  • Farming Conditions: Nursery or well-prepared grow-out ponds with stable water quality
  • Recommended For: Farms with moderate infrastructure and water quality management systems

Quality indicators

  • Consistent size uniformity across batch
  • Vigorous swimming and feeding behavior
  • Developing rostrum and appendages
  • Negative PCR results for WSSV, EHP, IHHNV and AHPND

Handling guidelines

  • Acclimatization period of 30-45 minutes to match farm conditions
  • Monitor dissolved oxygen during transport and stocking process
  • Stock during early morning or evening hours

Not sure which stage suits your pond?

Tell the zone team about your nursery, your pond preparation and your water. They will recommend a stage and confirm what is available for your date.

Bengal Zone

West Bengal

Ask for Alagarsamy

+91 97514 14892

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Chennai South Zone

Tamil Nadu

Ask for John Manoj

+91 99405 37604

Call WhatsApp