Brown spot disease in the material is associated with which condition?

• A. High feeding rates
• B. Poor water management and stress
• C. Cold water only
• D. Low stocking density

Answer: (B)

Brown spot disease is driven by environmental stress from poor water quality. When water management is inadequate, waste builds up, dissolved oxygen can fall, and toxins like ammonia rise. This stress weakens the animals’ immune defenses, making them vulnerable to opportunistic bacteria or fungi that cause skin lesions that appear as brown spots. So the condition most closely linked to brown spot disease is the combination of poor water management and the stress it creates. While high feeding rates can worsen water quality and thus increase risk, the fundamental issue is the stressful, suboptimal water environment. Cold water alone doesn’t account for it, and lower stocking density generally reduces stress and disease risk.