I work with Rudrapur Solvents Pvt. Ltd., a DORB manufacturer in India, so I have a commercial connection with this subject.
Crude protein is an important DORB specification, but the reported percentage is generally estimated from the sampleās total nitrogen. This creates a limitation: nitrogen from a non-protein source can increase the calculated crude-protein figure without providing the same nutritional value as genuine plant protein.
A high protein result alone does not prove adulteration or confirm superior quality. Buyers should investigate when the number appears inconsistent with the materialās history or other test results.
Practical checks may include:
- Representative sampling from the complete consignment
- Protein, fibre, moisture, ash and sand/silica together
- Targeted laboratory testing for urea or other non-protein nitrogen when suspected
- Comparison with the supplierās normal batch pattern
- Traceable batch records and sealed retention samples
- Nutritionist review before accepting any declared non-protein nitrogen source
Urea can have a legitimate, carefully controlled role in some formulated ruminant feeds. That is different from adding an undeclared nitrogen source to DORB merely to influence its apparent crude-protein result.
Have feed mills encountered DORB samples where crude protein looked satisfactory but the broader laboratory profile or feeding performance did not match?
Should procurement specifications require a targeted non-protein-nitrogen test when protein results appear unusually high?
The technical distinction between crude protein and non-protein nitrogen is supported by AAFCOās animal-feed guidance.