If crude protein requirements are computed, they should be approximately what percentage greater than the digestible protein requirements?

The correct percentage representing the difference between crude protein requirements and digestible protein requirements is typically around 20%. This discrepancy arises because crude protein measurements include all protein sources, not just those that are digestible or effectively utilized by the animal.

Crude protein is derived from the total nitrogen content of the feed, which is converted to protein value under the assumption that all nitrogen is from protein sources. However, not all of this protein is accessible or usable by the animal due to variations in digestibility based on feed type and other factors.

Consequently, to account for the digestible portion that impacts an animal's actual protein needs, crude protein requirements are adjusted upward, usually by about 20%. This ensures that the animal receives sufficient digestible protein to meet its physiological and production needs, factoring in limitations on protein utilization that wouldn't be evident from a simple measurement of crude protein. This percentage helps maintain optimal health, growth, and productivity in livestock when formulating diets.