A shrimp farmer notices that the shrimp are growing more slowly than expected. The first thought may be to increase the daily feed ration. After all, if shrimp receive more nutrition, shouldn't they grow faster?
Not always. Increasing feed helps only when the shrimp can consume and utilise the additional feed. If their appetite is limited by poor water quality, moulting, disease or other environmental conditions, adding more feed may increase waste rather than growth.
The important question is not simply how much feed goes into the pond, but whether the shrimp are consuming enough feed to support their growth. Understanding this difference can help farmers avoid unnecessary feed expenses and manage pond conditions more effectively.
When Does Increasing Feed Help Shrimp Grow?
Increasing feed can be beneficial when the existing ration does not meet the shrimp's actual requirements. For example, as shrimp grow and standing biomass increases, their total daily feed requirement may also rise.
However, the increase should be based on regular growth sampling, estimated biomass, feeding-tray observations and the farm's feeding programme. A ration that was sufficient last week may no longer be adequate if the shrimp population has grown significantly.
According to feeding-management guidance from the Marine Products Export Development Authority (MPEDA), farmers should sample shrimp regularly to assess growth, calculate feed requirements and monitor feed conversion ratio (FCR). Feeding rates should be adjusted according to observed conditions rather than increased arbitrarily.
Why More Feed Can Fail to Improve Growth
Consider a pond where shrimp have stopped consuming their usual ration. If the farmer responds by adding more feed without investigating the reason, the additional pellets may remain uneaten.
Several conditions can reduce feed intake:
- Low dissolved oxygen: Shrimp may reduce feeding when oxygen availability becomes inadequate.
- Moulting: Shrimp can temporarily reduce feed intake around moulting.
- Heavy rainfall or temperature changes: Sudden environmental changes can affect feeding activity.
- Disease or physiological stress: Unhealthy shrimp may not consume feed normally.
- Poor pond-bottom conditions: Accumulated organic waste and deteriorating water conditions can affect shrimp health and feeding behaviour.
Uneaten feed decomposes and adds organic matter to the pond. Its breakdown consumes oxygen and can contribute to deteriorating water quality. This may further suppress feeding, creating a cycle of lower feed consumption, increasing waste and rising production costs.
Therefore, when shrimp eat less than expected, farmers should investigate the cause before increasing the ration.
How Can Farmers Know Whether to Increase Feed?
Feeding decisions should combine observations rather than depend on a single sign.
- Check the feeding trays
Inspect trays according to the farm's feeding schedule. If feed is consistently consumed quickly across the monitored trays, the ration may need reassessment. If substantial feed remains, investigate why consumption is low before deciding the next ration.
- Estimate shrimp biomass
Conduct regular sampling to determine average shrimp weight and assess growth. Use the estimated surviving population and average body weight to calculate standing biomass and compare the result with the current feeding programme.
- Check water quality
Review dissolved oxygen, temperature, pH and other relevant water-quality parameters when feeding behaviour changes. A water-quality problem should be addressed rather than masked by adding more feed.
- Compare growth with feed consumption
If feed consumption is increasing but sampled shrimp growth is not improving, examine possible environmental, health or management constraints. FCR can help assess how efficiently feed is being converted into harvested biomass, although it should be interpreted alongside survival and growth data.
Why the Right Feed Quantity Matters More as Shrimp Grow
As shrimp biomass increases, feeding management becomes particularly important because the total quantity of feed entering the pond can rise considerably. More feed must be managed without allowing uneaten pellets and organic waste to accumulate.
Farmers should keep daily records of feed offered, feeding-tray observations, water quality, shrimp sampling and any changes in appetite. Comparing these records over time can help identify whether the ration needs adjustment or whether another factor is limiting growth.
Feeding schedules and adjustment percentages should follow appropriate farm protocols and be adapted to actual pond conditions. A single feeding rate cannot be applied to every pond because stocking density, shrimp size, survival, water quality and management systems differ.
The Takeaway: Feed According to Demand, Not Guesswork
More feed does not automatically mean faster shrimp growth. Increasing the ration can support production when shrimp biomass and actual feed requirements justify it. But when shrimp are eating less because of stress, poor water quality or health problems, additional feed may simply increase waste and costs.
The better approach is to monitor feeding trays, estimate biomass, track growth and check water quality before changing the ration.
In shrimp farming, the goal is not to put more feed into the pond. It is to ensure that the feed offered supports healthy growth without unnecessary waste.
