Step 1: Understanding the Concept:
Fat cow syndrome is a metabolic disorder.
It affects cows that are overfed in early pregnancy.
Step 2: Key Formula or Approach:
No specific formula.
Need to understand fat cow syndrome.
Step 3: Detailed Explanation:
Fat cow syndrome occurs in cows that are overfed early in pregnancy.
They suffer nutritional stress in the last 2 months before calving.
This leads to fatty liver and ketosis.
Thus, the disorder is fat cow syndrome.
Step 4: Final Answer:
The metabolic disorder is fat cow syndrome.
Hence, the correct option is (D).