Final answer:
Pseudo-Rabies is a viral disease that hogs can carry for a long time and appears as a fever, depression, vomiting, and nesting in older swine.
Step-by-step explanation:
The viral disease that hogs can carry for a long time and appears as a fever, depression, vomiting, and nesting in older swine is known as Pseudo-Rabies or Aujeszky's disease.
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