Analysis of the Application Effect of Beer Yeast in Aquaculture

      Beer yeast mainly plays a role in aquaculture through mechanisms such as nutritional enhancement, regulation of intestinal health, and improvement of stress resistance, especially during seedling cultivation and in stressful environments. The following are its core application effects and technical points:

1、 Core application effect

Improved survival rate and stress resistance

      Typical case: Adding 2% beer yeast to the feed of juvenile turbot resulted in a decrease in transportation mortality rate from 15% to 5% and an increase in survival rate by 20%.

      Mechanism of action: β - glucan enhances macrophage activity, while mannan adsorbs heavy metals and mycotoxins in water, reducing environmental stress damage.

Growth performance optimization

      Increased weight gain rate: Adding 2% beer yeast to the diet of tilapia fry resulted in a 25% increase in weight gain rate compared to the control group (35% vs 28%).

      Improvement in feed conversion rate: Adding 1.5% beer yeast to the feed of Penaeus vannamei resulted in an 8% reduction in feed to meat ratio and a 20% increase in specific growth rate (SGR).

Enhanced immune function

      Optimization of serum indicators: Rainbow trout experiments showed that the addition of beer yeast increased serum lysozyme activity by 30% and complement C3 content by 18%.

      Improvement in disease resistance: In the White Spot Syndrome (WSSV) challenge test of shrimp, the survival rate of the beer yeast group was 35% higher than that of the control group.

2、 Key points of using technology

Add dosage and stage adaptation

      Seedling stage: It is recommended to add 2% -3% (full price feed), which can be increased to 3% during the juvenile/shrimp stage.

      Adult fish period: Add 1% -2% routinely, and increase to 2.5% before high-density farming or transportation.

Product selection criteria

      Key indicators: viable cell count ≥ 1 × 10 ⁹ CFU/g (active type), β - glucan ≥ 5%, protein ≥ 45%.

      Process requirements: spray drying or freeze drying process products are preferred to retain more active ingredients.

Collaborative compatibility scheme

      Combined with probiotics: beer yeast+Bacillus subtilis (1:1 ratio), synergistically improves intestinal microbiota balance.

      Combination with polysaccharides: with astragalus polysaccharide (0.5%), the antiviral effect will be enhanced (for example, the incidence rate of koi herpesvirus will be reduced by 40%).

3、 Typical Cases and Data Validation

    Shrimp Seedling Experiment

    Experimental group: Basic feed+2% beer yeast

    Control group: Basic feed

result:

    Survival rate: 82% vs 68% (+20.6%)

    Body length growth rate: 1.2mm/day vs 0.9mm/day (+33.3%)

    Ammonia nitrogen tolerance: LC50 increased by 25% after 96 hours (from 25mg/L to 31mg/L)

Salmon farming application

      Processing: Add 1.5% beer yeast and 0.3% enzyme preparation to the feed

effect:

    Muscle fat content: 7.8% vs 6.5% (+20%)

    Liver to body ratio (HSI): 1.8% vs 2.2% (decreased by 18%, liver healthier)

4、 Cost and benefit analysis

    Cost comparison: The price of beer yeast is about 1/3-1/2 of fish meal, and adding 2% increases feed costs by about 1.5% -2%.

Return on investment:

    According to data from a certain breeding farm, adding 1kg of beer yeast (at a cost of about 20 yuan) can produce an additional 35kg of aquatic products per ton of feed (calculated at a market price of 15 yuan/kg, an increase of 525 yuan).

    The comprehensive benefit ratio (input-output ratio) is about 1:26.

5、 Industry Trends and Innovation Directions

    Functional oriented product development

    High selenium beer yeast: with a selenium content of ≥ 2000mg/kg, it enhances the antioxidant capacity of fish (such as increasing the compliance rate of selenium content in salmon muscle to 98%).

    Wall breaking yeast extract: releases intracellular nucleotides through enzymatic hydrolysis technology, promoting intestinal development in juvenile fish (such as a 15% increase in intestinal villus length).

Alternative use of antibiotics

    Experiment at a shrimp farm in Taiwan: Using 2.5% beer yeast instead of 50% antibiotics, the Vibrio infection rate decreased from 22% to 9%, and the survival rate of shrimp seedlings remained stable at over 85%.

6、 Application suggestions

    Precise feeding strategy: Use continuously for 2-3 weeks during the seedling stage, and alternate 1-2 weeks per month during the adult fish stage.

    Collaborative water quality management: using zeolite powder (1kg/m ³) to enhance the adsorption effect of water toxins.