Indicators of poor health are:
· Runny or crusty eyes or noses. This can be a sign of respiratory or eye infections. Such infections are generally treatable with antibiotics, so it’s not a reason to dismiss an animal immediately (especially if you’re at a shelter). But if a lot of the animals at a pet store or farm have these symptoms, it’s a sign that the owners aren’t taking good care of their pets, which could mean your potential pet has other problems, too.
· Ears. Head shaking and scratching may be a sign of fleas, ear mites, excess wax, or infection. Again, these maladies usually can be treated, but consider the cost involved and the care the animal has received in the past.
· Mouth and teeth. You may need help looking into the mouth of some animals, but even quickly checking out the teeth can tell you a lot about their health. Teeth that are overgrown or crooked (also called maloccluded) will need to be trimmed, straightened, or removed, for instance. · Feathers, fur, skin, and scales. In general, you’re looking for smooth, shiny fur and feathers, without large bald patches or visible dandruff. Fish should have intact bodies (i.e., no torn fins) and should be free of white or mold-like spots.
· Private parts. You may feel squeamish about this, but just as you’re familiar with your young child’s privates, you need to get familiar with your pets’ regions. The area around the anus and down the hind legs of your potential pet should be fairly clean. Matted feces can be a sign of digestive disorder; urine-soaked fur can be a sign of a bladder infection or incontinence. Urine-soaked or poop-smeared bodies also can be a sign of poor care on the part of the owner.
Finding healthy pet references: http://www.drspock.com/article/0,1510,5147,00.html