Question

Parakeratosis, a skin condition characterized by incomplete keratinization of the epithelial cells, is caused by the dietary deficiency of:

• A. Copper
• B. Zinc
• C. Iron
• D. Cobalt

Hint:

Associate Zinc directly with skin integrity:
- Swine $\rightarrow$ Parakeratosis.
- Dogs $\rightarrow$ Zinc-responsive dermatosis (crusts around the eyes, muzzle, and joints).
- High Calcium levels in feed antagonize Zinc, triggering these symptoms.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Trace mineral deficiencies are responsible for various metabolic, reproductive, and integumentary disorders in livestock.
Zinc is an essential cofactor for over 300 enzymes, playing a central role in nucleic acid synthesis, cell division, and keratinization of epidermal tissues.

Step 2: Detailed Explanation:
Let us review the skin pathology associated with zinc deficiency:
- Parakeratosis: A condition defined by the retention of nuclei in the stratum corneum of the epidermis, representing incomplete or abnormal keratinization.
- In pigs, dietary zinc deficiency (often exacerbated by high dietary calcium or phytate, which interfere with zinc absorption) causes classic Swine Parakeratosis.
- This is clinically characterized by thick, crusty, fissured skin lesions, primarily on the limbs, ears, and snout, along with reduced growth rates.
- Copper deficiency causes achromotrichia (loss of hair color) and cardiovascular/skeletal defects.
- Iron deficiency causes microcytic hypochromic anemia (especially in piglets).
- Cobalt deficiency causes vitamin B12 deficiency (anemia, wasting).

Step 3: Final Answer:
Therefore, parakeratosis is caused by the dietary deficiency of zinc.