Fiber analysis is one of the most important routine tests in feed and forage laboratories.

Parameters such as:

• ADF (Acid Detergent Fiber)
• NDF (Neutral Detergent Fiber)

are widely used to evaluate:

• Feed digestibility
• Animal intake potential
• Nutritional quality

The Fibertec 8000 automates the boiling, rinsing, and extraction steps required for detergent fiber analysis, helping laboratories improve repeatability and reduce manual handling.

Principle of Fiber Analysis

Fiber analysis separates specific structural components from feed materials.

NDF Measures

• Hemicellulose
• Cellulose
• Lignin

NDF is commonly associated with:

• Feed intake
• Bulkiness
• Rumen fill

ADF Measures

• Cellulose
• Lignin

ADF is often related to:

• Digestibility
• Energy availability

Higher ADF values usually indicate lower digestibility.

Typical Workflow

1. Sample Preparation

Samples should be:

• Uniformly ground
• Dry
• Properly mixed

Typical particle size:

• 1 mm grinding recommended

Accurate grinding is critical for repeatable filtration performance.

2. Sample Weighing

Typical sample weight:

Samples are placed into Fibertec filter crucibles before analysis.

3. Reagent Addition and Boiling

The Fibertec 8000 automatically controls:

• Reagent filling
• Heating
• Boiling time
• Rinsing cycles

Typical Conditions for NDF

Typical Conditions for ADF

4. Rinsing and Extraction

After boiling:

• Samples are rinsed thoroughly
• Residual detergent is removed
• Acetone extraction helps drying efficiency

Proper rinsing is essential for stable results.

Insufficient rinsing may cause:

• High residue weight
• Poor repeatability
• Increased blank values

5. Drying and Ashing

Typical procedure:

Drying removes moisture while ashing removes mineral residue.

Final fiber percentage is calculated from residue weight differences.

Basic Fiber Calculation

ADF or NDF results are generally calculated as:

$Fiber(\%) = \frac{Residue\ Weight – Blank}{Sample\ Weight} \times 100$Fiber(%)=Sample WeightResidue Weight−Blank​×100

Accurate blank correction is very important for reliable data.

Common Troubleshooting Points

Weak Pressure During Discharge

Possible causes:

• Air leaks
• Trap contamination
• Weak pressure pump
• Valve leakage

Slow Filtration

Possible causes:

• Fine sample particles
• Overloaded crucibles
• Dirty filters
• Foam contamination

Overflow During Reagent Filling

Possible causes:

• Incorrect calibration
• Pump instability
• Sensor problems
• Blocked tubing

Poor Repeatability

Possible causes:

• Inconsistent grinding
• Incomplete rinsing
• Residual detergent
• Uneven drying

Good Laboratory Practices

For stable long-term operation:

• Clean crucibles immediately after use
• Inspect tubing regularly
• Monitor pressure and vacuum performance
• Replace worn silicone tubes
• Perform routine pump calibration checks

Preventive maintenance is essential for stable fiber analysis performance.

Final Thoughts

ADF and NDF analysis remain critical tools for evaluating feed quality and digestibility.

With the Fibertec 8000, laboratories can achieve:

• Improved automation
• Better repeatability
• Reduced operator workload
• Stable routine performance

Proper sample preparation and preventive maintenance remain the keys to reliable fiber analysis.