Must my dog's nose be wet for it to be healthy?

• Fluid from the lateral glands in a dog's nose lubricates the external part of the nostrils and makes them shiny. As a result, a moist nose is generally believed to be a sign of a healthy dog, but this is not a invariably true.
  
• A dog that has slept in a hot place may have a dry nose on waking, because of slight dehydration. Once the dog cools down and has a drink, the nose will soon look moist again.
  
• Dogs that have suffered from distemper early in life, however, may have permanently dry noses because of the infection's long-term effect on the nasal glands.