In the energy-balanced example, what is the final percentage composition of grain mix A in the total ration?

In the energy-balanced example, what is the final percentage composition of grain mix A in the total ration?

• A. 60% A and 40% B
• B. 40% A and 60% B
• C. 45% A and 55% B
• D. 55% A and 45% B

Answer: (D)

Energy balance in feed formulation means adjusting the proportions of feeds with different energy densities so the total energy of the ration exactly matches the target. Think of x as the fraction of grain mix A in the total mix. If E_A and E_B are the energy densities of A and B, the final energy per unit of the ration is x·E_A + (1 − x)·E_B. To meet the energy requirement E_req, you set x·E_A + (1 − x)·E_B = E_req and solve for x: x = (E_req − E_B) / (E_A − E_B). Since grain A provides more energy per unit than grain B, the solution will fall between 0 and 1 and tilt toward A when the target energy sits closer to A’s energy density. In this example, solving gives x = 0.55, so the final mix is 55% grain mix A and 45% grain mix B. This arrangement hits the energy target exactly without overfeeding or underfeeding energy; a higher share of A would overshoot, and a lower share wouldn’t reach the requirement.

Energy balance in feed formulation means adjusting the proportions of feeds with different energy densities so the total energy of the ration exactly matches the target. Think of x as the fraction of grain mix A in the total mix. If E_A and E_B are the energy densities of A and B, the final energy per unit of the ration is x·E_A + (1 − x)·E_B. To meet the energy requirement E_req, you set x·E_A + (1 − x)·E_B = E_req and solve for x: x = (E_req − E_B) / (E_A − E_B). Since grain A provides more energy per unit than grain B, the solution will fall between 0 and 1 and tilt toward A when the target energy sits closer to A’s energy density. In this example, solving gives x = 0.55, so the final mix is 55% grain mix A and 45% grain mix B. This arrangement hits the energy target exactly without overfeeding or underfeeding energy; a higher share of A would overshoot, and a lower share wouldn’t reach the requirement.