Net energy for production (NEP) is defined as the portion of net energy available for production after covering maintenance energy.

• A. The energy required for maintenance only
• B. The energy available for production after maintenance needs are met
• C. The energy lost as heat during digestion
• D. The total energy in the feed

Answer: (B)

In livestock energy budgeting, energy intake is split between what’s needed to keep the animal alive (maintenance) and what can be used for production (growth, lactation, etc.). Net energy for production is the portion of net energy that remains after the animal’s maintenance requirements are met. For example, if the animal’s net energy supply is 1000 kcal/day and it requires 600 kcal/day for maintenance, the NEP is 400 kcal/day. That 400 kcal/day is what can be invested in production.

The other options don’t fit because:

• Maintenance energy is the amount needed to sustain basic functions, not what’s left for production.

• Energy lost as heat during digestion is heat increment, not the portion available for production.

• The total energy in the feed refers to gross energy (or a broader energy measure), not the portion specifically available for production after maintenance.