Researchers found a promising way to protect farmed shrimp from a deadly disease without using antibiotics. They created a special water system containing helpful bacteria and algae, and added nutritious supplements to shrimp feed. When shrimp were exposed to the disease-causing bacteria, those raised in this system survived just as well as shrimp treated with antibiotics. This discovery is important because the disease-causing bacteria are becoming resistant to antibiotics, making them harder to treat. The new method could help shrimp farmers protect their animals while reducing antibiotic use.

The Quick Take

  • What they studied: Whether a special water system with helpful bacteria and algae, combined with nutritious feed supplements, could protect shrimp from a serious disease without using antibiotics
  • Who participated: Farmed white-leg shrimp (Penaeus vannamei) raised in controlled water systems over an 84-day period. The study compared different treatment groups including shrimp in the special biofloc system, shrimp with added feed supplements, and shrimp treated with antibiotics
  • Key finding: Shrimp raised in the biofloc system with helpful bacteria and algae survived a disease challenge 70% of the time, which was nearly as good as shrimp treated with antibiotics (73% survival). This suggests the natural system works almost as well as medication
  • What it means for you: If you eat farmed shrimp, this research suggests farmers may soon have better ways to keep shrimp healthy without relying on antibiotics. This could mean safer seafood and help slow down antibiotic resistance. However, this research is specific to shrimp farming and doesn’t directly affect human nutrition or health

The Research Details

Scientists created a special water system for shrimp farming by adding helpful bacteria (Halomonas alkaliphila), other bacteria that clean the water, and algae (Chaetoceros calcitrans) to shrimp tanks. They also created special feed containing seaweed powder, spirulina (a type of algae), and freeze-dried helpful bacteria. The shrimp were divided into different groups: some lived in the special water system alone, some got the special feed, some got both, and some were treated with antibiotics as a comparison. All groups were raised for 84 days, then exposed to the disease-causing bacteria to see how well they survived.

The researchers measured water quality, how much the shrimp grew, how many survived, and studied the shrimp’s immune system at the genetic level. They looked at whether the shrimp’s bodies produced natural disease-fighting proteins when exposed to the harmful bacteria.

This approach is important because it tests whether natural solutions can replace antibiotics. The disease being studied (AHPND) is caused by bacteria that have become resistant to many antibiotics, making treatment difficult. By studying how helpful bacteria and algae can boost shrimp’s natural defenses, researchers can find sustainable alternatives that don’t contribute to antibiotic resistance—a major public health problem

This is a controlled laboratory study where researchers carefully managed all conditions, which is good for understanding cause and effect. The study measured multiple outcomes including survival rates, water quality, and immune system markers, which strengthens the findings. However, the specific sample size wasn’t provided in the abstract, which makes it harder to assess statistical power. The study was published in a peer-reviewed scientific journal, indicating it met professional standards. Real-world farm conditions may differ from controlled laboratory settings

What the Results Show

The main finding was that shrimp raised in the biofloc system (the special water with helpful bacteria and algae) survived the disease challenge at a rate of 70%, which was nearly identical to shrimp treated with the antibiotic enrofloxacin (73% survival). This suggests the natural system works almost as well as medication for protecting shrimp from this deadly disease.

Water quality remained more stable in the biofloc systems compared to traditional farming methods. The shrimp also grew larger and more shrimp survived overall during the 84-day growing period when using the biofloc system. Interestingly, adding the special feed supplements to the biofloc system didn’t significantly improve results beyond what the biofloc system alone achieved.

When researchers examined the shrimp’s immune systems at the genetic level, they found that shrimp in the biofloc systems produced more natural disease-fighting proteins called antimicrobial peptides. These are like the shrimp’s natural antibiotics. The shrimp also showed increased activity in their melanization process, which is another immune defense mechanism that helps fight infections.

The biofloc system provided additional benefits beyond disease protection. It improved overall water quality by maintaining more stable conditions, which reduces stress on the shrimp. The system also provided extra nutrition through the algae and bacteria, which may have contributed to better growth. The fact that the synbiotic feed supplements (the special food additions) didn’t add much benefit beyond the biofloc system alone suggests that the water system itself is the key factor. This is actually good news for farmers because it means they don’t necessarily need to add expensive supplements if they use the biofloc system

This research builds on growing evidence that probiotics (helpful bacteria) and prebiotics (food for helpful bacteria) can boost shrimp health. Previous studies have shown that biofloc systems improve water quality and shrimp growth, but this is one of the first studies to directly compare biofloc systems to antibiotic treatment for disease protection. The results are encouraging because they show the natural approach works nearly as well as medication. This aligns with broader research showing that boosting animals’ natural immune systems can be as effective as treating infections after they occur

The study was conducted in controlled laboratory conditions, which may not perfectly reflect what happens on actual shrimp farms where conditions are more variable. The specific number of shrimp tested in each group wasn’t provided, making it difficult to assess how reliable the results are statistically. The study only tested one type of disease and one species of shrimp, so results may not apply to other shrimp species or other diseases. The long-term effects of this system weren’t studied—we only know what happened over 84 days. Additionally, the cost-effectiveness of setting up and maintaining these biofloc systems compared to traditional farming wasn’t evaluated

The Bottom Line

For shrimp farmers: Consider transitioning to biofloc systems as a way to reduce antibiotic use while maintaining shrimp health and survival rates. The evidence suggests this approach is effective and sustainable. Start with small-scale trials before converting entire operations. For consumers: This research supports choosing farmed shrimp from producers using sustainable practices like biofloc systems, as it may indicate lower antibiotic use. Confidence level: Moderate—the results are promising but need confirmation in real-world farm settings

Shrimp farmers and aquaculture companies should care most about this research, as it offers them a practical alternative to antibiotics. Seafood consumers concerned about antibiotic resistance and sustainable farming practices should also pay attention. Public health officials interested in reducing antibiotic use in agriculture would find this relevant. This research is less directly relevant to people who don’t eat shrimp or those primarily concerned with human medicine, though antibiotic resistance is a global health issue affecting everyone

In controlled conditions, the biofloc system showed protective effects within 84 days. On actual farms, it may take several months to establish the system and see consistent results. Farmers should expect to see improvements in water quality within weeks, but disease protection benefits would likely take 2-3 months to fully establish as the helpful bacteria populations build up

Want to Apply This Research?

  • If you’re a shrimp farmer using this app, track weekly water quality parameters (ammonia, nitrite, nitrate levels) and monthly survival rates and growth metrics. Compare these metrics before and after implementing the biofloc system to measure real-world effectiveness
  • For farmers: Implement biofloc system setup by inoculating tanks with the specified bacteria and algae strains, maintaining proper carbon-to-nitrogen ratios, and monitoring water conditions regularly. For consumers: Research and choose seafood products from farms using biofloc or other sustainable systems when possible
  • Track disease outbreak rates and antibiotic usage over time. Monitor shrimp survival rates, growth rates, and water quality parameters monthly. Document any disease incidents and compare them to baseline data from before implementing the biofloc system. This long-term tracking helps determine if the system maintains effectiveness over multiple production cycles

This research is specific to shrimp farming and aquaculture practices. It does not provide medical advice for humans. While the findings suggest biofloc systems may reduce the need for antibiotics in shrimp farming, individual farm results may vary based on local conditions, management practices, and specific bacterial strains used. Farmers should consult with aquaculture specialists before implementing these systems. This research was conducted in controlled laboratory conditions and may not perfectly reflect real-world farm outcomes. The study has not been independently verified in large-scale commercial farming operations. Always follow local regulations regarding aquaculture practices and antibiotic use in your region.