Topics:
Animal Nutrition, Animal Refresher
Examples of Natural Bypass Protein
Which of the following is an example of Natural By-pass protein?
- Maize & feather meal — Correct Answer
- Urea & casein
- Maize & urea
- All the above
Explanation:
Correct Answer: Maize and Feather meal
Natural bypass (rumen-undegradable) proteins are those that resist microbial degradation in the rumen due to their physical or chemical structure. Maize (corn) protein (zein) is naturally heat-denatured/resistant, and Feather meal has a rigid β-keratin structure resistant to rumen proteolysis.
Bypass Protein Classification
| Category | Examples | Rumen Degradability |
|---|---|---|
| Natural high bypass | Maize (zein), Feather meal, Blood meal | 20–40% degraded |
| Processed bypass | Formaldehyde-treated soybean, Heat-treated proteins | Variable |
| Highly degradable (low bypass) | Urea, Casein, Soybean meal | 85–100% degraded |
Why Feather Meal is Bypass Protein
- Feather keratin has extensive disulfide crosslinks that make it resistant to rumen microbial proteases.
- Hydrothermal processing improves digestibility while retaining significant bypass fraction.
- Feather meal contains ~85% CP but requires high-pressure steam treatment for utilization.
Why Other Options Are Wrong
- Urea & casein → completely rumen-degradable; opposite of bypass protein.
- Maize & urea → urea is 100% degradable; not bypass.
- All the above → Urea and casein are not bypass proteins.
📚 About this Topic — Animal Nutrition
This multiple choice question is from Animal Nutrition, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Nutrition to strengthen your preparation.
