Polychaetes, or marine worms, are an essential part of shrimp farming, particularly as a key dietary component for broodstock. When fed live, polychaetes such as palolo worms, lugworms, and sand worms naturally enhance broodstock maturation, leading to increased offspring production and healthier shrimp populations. However, careful consideration of where and how these polychaetes are sourced can further strengthen shrimp farming practices — in particular biosecurity — ensuring long-term success and sustainability.
Polychaetes and Shrimp Pathogens: A Balanced Perspective
Polychaetes play a natural role in marine ecosystems, filtering nutrients from sand and mud. This filter-feeding behaviour, while beneficial, can expose them to microorganisms in their environment. In some cases, these microorganisms may include shrimp-specific pathogens, such as Enterocytozoon hepatopenaei (EHP) and Vibrio species. Although the impact is difficult to assess, this highlights the importance of thoughtful sourcing and handling practices for polychaetes used in shrimp farming.
EHP, for instance, is a resilient microsporidian parasite that can affect shrimp health. Research has shown that this pathogen may be present in the gut contents of polychaetes collected from certain areas. The environment where polychaetes are harvested plays a significant role in their pathogen profile.
For example, polychaetes collected directly from shrimp farming areas have been found to be 22% EHP-positive, compared to just 3% of polychaetes from wild, non-farming areas (Krishnan et. al. 2021). This underscores the importance of carefully selecting harvest locations and avoiding areas with known pathogen presence when managing biosecurity and risk. By being mindful of sourcing, shrimp farmers can minimize the potential for introducing microorganisms while still benefiting from the nutritional value of polychaetes. Specific Pathogen Free (SPf) polychaetes reared under biosecure conditions should be prioritised for use where available.
When it comes to marine worms, it's not just EHP to be wary of. Other pathogens like Vibrio spp. can sometimes be found in the gut of wild-caught polychaetes too. Understanding these dynamics allows shrimp farmers to make informed decisions about their inputs and adopt practices that reduce the likelihood of introducing unwanted pathogens into farming environments.
The Benefits of Strategic Sourcing
Locally harvested polychaetes are widely used in shrimp farming due to their availability, affordability and positive impact on broodstock maturation. To maximize the benefits of these live feeds while minimizing potential concerns, it’s helpful to focus on sourcing polychaetes from reliable suppliers or controlled environments.
Using Specific Pathogen Free (SPf) polychaetes is one of the most effective strategies to ensure the health and productivity of shrimp farms. SPF worms are cultivated in carefully managed conditions, making them a consistent and dependable choice. They offer a practical way to support biosecurity and reduce risk, without compromising the nutritional value that live polychaetes provide.
For farmers who prefer a more hands-on approach, breeding polychaetes in-house is another exciting opportunity. Cultivating polychaetes on-site allows for greater control over their environment and feeding conditions, aligning with sustainable farming practices. Although this requires an upfront investment in time and resources, it offers long-term rewards by fostering a self-sufficient system, and can be performed in closed biosecure facilities.
Supporting Shrimp Health Through Proactive Practices
The role of polychaetes in shrimp farming highlights the importance of proactive management. Testing polychaetes, for example, is an excellent way to gain insight into their pathogen profile before use. While testing live polychaetes can be challenging due to their feed scheduling requirements, this step can provide valuable peace of mind when sourcing locally harvested supplies. Combining this with water treatment processes and routine monitoring increases biosecurity, reduces risk and increases likelihood of a clean and well-maintained farming environment.
Water quality, in particular, is a cornerstone of shrimp health. Treating water inputs from external sources, including polychaete harvesting areas, adds an extra layer of assurance. These measures not only reduce potential risks but also create a more stable environment for shrimp to thrive.
Pathogen-Free Solutions: The Future of Polychaete Use
The shrimp farming industry continues to evolve with innovative approaches in managing inputs. As more farmers explore pathogen-free polychaetes and in-house breeding programs, the sector is setting itself up for sustainable success. By focusing on solutions that combine efficiency with environmental awareness, shrimp farmers can enhance productivity and maintain the well-being of their stock.
Polychaetes remain an integral part of shrimp farming, and their value in broodstock diets is undeniable. Through mindful sourcing and forward-thinking practices, farmers can unlock the full potential of these remarkable nutritional resources while supporting the health and resilience of their shrimp populations.
Building Confidence in the Industry
Biosecurity audits are an invaluable tool for shrimp farmers looking to optimize inputs testing and maintain regular health monitoring of their stock. By identifying and addressing potential risks, such as those associated with feed inputs like polychaetes, these audits support better farm management and healthier shrimp populations. Services like those offered by Genics incorporate advanced diagnostics and expert advice, helping farmers strengthen their biosecurity measures while fostering sustainable farming practices.
The positive role of polychaetes in shrimp farming reflects the broader opportunities within the industry — particularly in Indonesia — to embrace best practices and innovation. Farmers who adopt these strategies can feel confident in their ability to achieve strong production outcomes, maintain biosecurity, and contribute to the ongoing growth of shrimp aquaculture. With continued research, collaboration, and commitment to quality, the future of shrimp farming in Indonesia looks brighter than ever.
Reference:
Krishnan, A.N. et al. (2021) ‘Polychaete worm - a passive carrier for Enterocytozoon hepatopenaei in shrimp’, Aquaculture, 545, p. 737187. doi:10.1016/j.aquaculture.2021.737187.
