Shrimp farmers commonly use live Artemia (brine shrimp) to supplement commercial feed during the rearing period of postlarvae (PL) of Pacific white shrimp (Penaeus vannamei). This practice helps shrimp grow larger and stronger, ultimately leading to better performance in grow-out ponds. However, Artemia production is limited and subject to fluctuations in yield and quality.
This is where nematodes, microscopic worms, come in as a potential solution. A recent study published by researchers from the University of Algarve (UAlg), the Federal University of Santa Catarina (UFSC), and E-Nema in the journal Animals explored the potential of using nematodes as a replacement for live Artemia in a co-feeding regimen for Pacific white shrimp (Penaeus vannamei) postlarvae reared in a biofloc system.
Why consider alternatives to Artemia?
Artemia production mainly comes from a handful of natural and artificial salt ponds around the world. These sources are subject to fluctuations in yield and quality, making Artemia a potentially unstable and expensive food source.
Why nematodes?
Nematodes, or roundworms, have emerged as a promising option and offer several advantages for shrimp aquaculture:
- Easy to cultivate: Unlike Artemia, which requires specific conditions in natural or artificial salt ponds, nematodes can be easily produced in controlled environments.
- Long-term storage: Nematodes can be dehydrated and stored for long periods, making them readily available when needed.
- Nutritional profile: Nematodes are rich in protein and essential fatty acids, crucial for the healthy growth and development of shrimp.
Previous studies have successfully used nematodes as live feed for P. vannamei during the hatchery phase, but their potential benefits during the rearing phase remain unexplored.
The study: Can nematodes replace Artemia?
This study aimed to evaluate the supplementation of Panagrolaimus sp. (strain NFS-24-5) nematodes for P. vannamei postlarvae reared in a biofloc nursery system as a possible substitute for Artemia nauplii.
The researchers compared the performance of shrimp fed different diets in a biofloc system:
- Control group (C): Only dry commercial feed.
- Artemia-artificial feed group (AA): Commercial feed mixed with a processed dry Artemia product.
- Live Artemia group (LA): Commercial feed supplemented with live Artemia.
- Nematode group (N): Commercial feed supplemented with dehydrated nematodes (Panagrolaimus sp.).
The results: Promising for nematode use
The study found that while shrimp fed dry diets grew faster, the groups that received live feed (both Artemia and nematodes) had significantly higher survival rates after 20 days. Interestingly, the nematode group showed lower nitrite levels, possibly due to changes in water chemistry caused by their presence.
Implications for the shrimp industry
The study’s findings suggest that nematodes could be a viable substitute for live Artemia in co-feeding regimens for Pacific white shrimp postlarvae reared in biofloc systems. This could offer shrimp farmers a more reliable and potentially cost-effective option to improve the health and survival of their young shrimp.
In this way, the successful application of nematodes as live feed could revolutionize shrimp hatchery practices. This innovation has the potential to increase farm efficiency, improve sustainability, and ultimately contribute to a more secure and productive shrimp aquaculture sector.
Conclusions
This study suggests that nematodes could be a viable alternative to Artemia in co-feeding regimens for shrimp hatcheries in biofloc systems. The benefits include:
- Improved survival rates for shrimp larvae.
- Enhanced sustainability: Reduced dependence on Artemia production could lead to a more stable and sustainable shrimp farming industry.
While these results are encouraging, further research is needed to fully understand the long-term effects of nematode use and optimize their integration into shrimp aquaculture practices.
The study was funded by the National Council for Scientific and Technological Development (CNPq) and the Foundation for Science and Technology.
Reference (open access)
Sommer, N. P., Martins, M. A., Rezende, P. C., Seiffert, W. Q., Seychelles, L. H., Aragão, C., & Vieira, F. B. (2024). Nematodes Can Substitute Artemia in a Co-Feeding Regime for Pacific White Shrimp Post-Larvae Reared in a Biofloc Nursery System. Animals, 14(18), 2679. https://doi.org/10.3390/ani14182679
