Question

The dietary requirement of macro minerals of animals is expressed as

• A. Miligrams per kilogram of the diet
• B. Percent of the diet
• C. Micrograms per kilogram of the diet
• D. Kilogram per kilogram of diet

Hint:

An easy way to distinguish mineral classifications in feed formulation is: Macro minerals = % of the diet (parts per hundred).
Micro minerals = ppm or mg/kg of the diet (parts per million).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Minerals are divided into macro minerals and micro (trace) minerals based on the quantities required by the animal body.
Macro minerals are needed in relatively large amounts, whereas micro minerals are needed in very small quantities.

Step 2: Detailed Explanation:
Macro minerals include calcium, phosphorus, magnesium, sodium, potassium, chlorine, and sulfur.
Because they are required in quantities of grams per day, their dietary concentration is high.
Therefore, their requirements are expressed as a percentage (%) of the total dry matter of the diet.
For example, a typical dairy cow diet may require \(0.6\%\) calcium and \(0.4\%\) phosphorus.
On the other hand, micro minerals (such as iron, copper, zinc, manganese, selenium, iodine, and cobalt) are required in milligram quantities.
Their dietary concentration is expressed as milligrams per kilogram (\(\text{mg/kg}\)), which is equivalent to parts per million (ppm).
Extremely rare trace elements might be expressed in micrograms per kilogram (\(\mu\text{g/kg}\) or ppb).
Expressing macro minerals as percent of the diet is standard in feed formulation software.

Step 3: Final Answer:
The dietary requirement of macro minerals is expressed as a percent of the diet.