ANSC Feeds Practice Exam

Which supplement should be fed to a cow on forage that contains 60% TDN and 6% crude protein?

1. 15% protein range cube

2. 20% protein range cube

3. 25% protein range cube

4. 30% protein range cube

The correct answer is: 20% protein range cube

The recommended choice is a 20% protein range cube for a cow on forage with 60% Total Digestible Nutrients (TDN) and 6% crude protein. This recommendation is based on balancing the nutritional needs of the cow to ensure she receives adequate protein that complements the forage she is consuming. Forage that has 60% TDN indicates moderate energy content, while the 6% crude protein is relatively low. Cows require a certain level of protein for optimal health, growth, and milk production. A 20% protein supplement would help elevate the protein content of the overall diet, supporting the cow's requirements without excessively overshooting the protein intake, which could lead to inefficient nutrient use and increased nitrogen waste. Feeding a supplement with a higher protein content, such as 25% or 30%, may provide excessive protein relative to the cow's needs, which may not be cost-effective or beneficial in the long run. Option A, a 15% protein cube, may not adequately address the protein deficiency in the diet, leaving the cow lacking in essential nutrients. Thus, the 20% protein range cube represents a balanced approach, providing sufficient protein to support the animal’s needs effectively.