Which sign might indicate disease in cattle?

The presence of reduced appetite, abnormal posture, nasal discharge, and changes in behavior is a clear indication of potential disease in cattle. Each of these signs points toward health issues that could be affecting the animal. For instance, a reduced appetite indicates that the animal may be feeling unwell or is in pain, as healthy cattle usually display a strong desire to eat. Abnormal posture can suggest discomfort or distress, while nasal discharge might be a symptom of respiratory illness or infection. Changes in behavior often accompany health issues; an animal that is normally social may isolate itself or show signs of agitation when it is not feeling well.

In contrast, increased energy and activity typically signify good health, while a normal appetite and behavior are signs that the animal is likely well. Lastly, no observable signs would not provide useful information about the health status of the cattle, as animals often exhibit subtle changes when they are unwell. Together, the presence of several abnormal signs (as indicated in the correct choice) is key in identifying and addressing potential health problems in cattle.