Just like with humans, a dog's overall health can be monitored by keeping track of what goes in...as well as what comes out. But how do you know what's normal for your dog and what might warrant a closer inspection?

Holistic veterinarian Dr. Judy Morgan has spent a lot of time looking at dog's poop in photos and in 3-D. "I am probably one of the few people in the world that receives daily poop photos in their inbox," she writes on her website. Morgan obviously has lots to say about the varying size, color and quality of a pup's poop. "Stools should be well formed and firm, [and] easy to pick up," Morgan noted. She added that they should have a little moisture but not be too wet or too dry.

Here are her tips for decoding the texture, color and odor of your dog's doo.

Texture

Stools that are too dry could indicate constipation or dehydration. If you dog seems to struggle when she goes, or if she's producing small dry nuggets, try increasing her water intake for a few days to see if that helps. On the other hand, stools that are too wet or too loose are a sign of diarrhea, which could be caused by anything from a change in diet to something more serious, such as cancer. If the loose stools persist for more than a day or two, or if they are accompanied by other symptoms (fatigue, blood in the stools, loss of appetite) you should check in with your dog's doc.

One more thing to check for is mucous. Stools that are covered in a shiny mucous casing could indicate an inflammation in the bowel that should be checked out by a vet.

Color

There's no delicate way to say this: Your dog's doo should be brown. Not too dark or too light — just plain old milk chocolate brown. If your dog's stools are dark brown, black or tarry, he could have blood in his small bowel or intestine. If his poop is light tan or yellow, it could be a liver problem or another issue within the digestive system such as a food allergy. Gray, greasy poop might indicate a condition called exocrine pancreatic insufficiency (EPI), which is also called maldigestion and could indicate a problem with the pancreas. Stools that are bright red could mean a cut or injury right around the rectum or a more serious issue further up the line.

What about white dog poop? That could mean two things. Back in the day, it was pretty common to see chalky white dog poop at the playground and along the sidewalk. Remember that stuff? White dog poop was more common in the old days because meat and bones were a larger part of many dogs' diets than they are today. When the poo from that diet sat out in the sun, the water evaporated, leaving a chalky white calcium coating behind. If your dog eats a lot of meat or bones and has white stool, that is why. But if the stool has white polka dots or looks like there are sections of white rice within it — that's likely caused by worms and it means it's time to check in with your vet.

Smell

Let's face it, your dog's stools are never going to smell good. But if they smell really bad it could mean that your pup has undigested food or a microbial imbalance in her digestive system. Talk to your veterinarian to see if a probiotic would be a good solution.