Why Does My Dog Poop Hard, Then Soft?

We all know that a dog's stool needs to have a certain consistency, neither too soft nor too hard, to be considered normal or healthy. However, many dogs start passing hard stool that ends up turning soft toward the end.

This curious change in texture can, in a way, point to a possible condition in the digestive tract. Let's take a detailed look at the reasons stool consistency can vary within a single bowel movement.

What Can Cause a Dog to Pass Hard Stool That Turns Soft?

First, it's worth noting that diarrhea is defined as a change in the frequency, consistency, and/or volume of bowel movements. The most common types of diarrhea are osmotic and those due to permeability disorders.

One direct consequence of diarrhea is the loss of water and electrolytes, resulting in dehydration and electrolyte imbalance. Dehydration leads to low blood volume (hypovolemia) and poor oxygen delivery to tissues, with all the consequences that entails.

The point here is that diarrhea that persists for several days could have serious consequences for our pet's body. That said, if our dog shows this type of diarrhea (hard then soft) only once or twice and it then goes away, it may not be clinically significant.

If, on the other hand, it continues over time, we should pay attention and check with the vet that everything is okay.

Small Intestine Conditions

This episode of diarrhea usually corresponds to conditions in the small intestine. The first part of the stool we see is firm — water has been properly absorbed from it by the large intestine — but the final part is soft, a sign that there may be some condition further up the tract (in the small intestine). The main ones can be:

• Enteritis: inflammation of the small intestine itself. It can be caused by multiple things: diet (spoiled food, sudden changes, something didn't agree with the dog, etc.), certain drugs, intestinal parasites, toxins, foreign bodies (objects)…
• Maldigestion/malassimilation: the faulty transport of nutrients from the digestive tract to the body's fluids, so to speak. It's divided into digestion failures (maldigestion) and mucosal transport failures (malabsorption).
• IBD, or inflammatory bowel disease: diarrhea or other intestinal symptoms occur along with weight loss, due to hypersensitivity reactions to antigens. Mucosal damage leads to poor nutrient absorption and, with it, diarrhea.

How to Tell If a Dog Has a Small Intestine Condition?

Several symptoms can accompany a small intestine condition, along with stool that starts hard and ends soft. They may not all occur together, but as a whole, they'd point to small intestine disease (though this doesn't rule out other organs being involved). These can be:

1. Diarrhea: sudden onset of diarrhea.
2. Vomiting.
3. Dehydration.
4. Listlessness.
5. Apathy.
6. Abdominal pain (intestinal loops full of fluid and gas).

What Veterinary Tests Will My Dog Need?

The vet will need to take a thorough history of the episode. We'll need to provide all the details we know, since these will help form an initial idea. This includes: how long it's been going on, what it's looked like (how the diarrhea presents), how it's evolved, diet type, any sudden diet change, whether it's eaten anything outside its usual diet, age, etc. The vet will then perform a general physical exam.

As for additional tests, these will be to rule out other conditions and confirm the type of diarrhea, since as you can see, there are many types and causes. Usually the first is an (abdominal) X-ray.

Two views (lateral and with the animal on its back) will give the vet an initial general idea of where the diarrhea is coming from, based on inflammation or gas buildup in the digestive tract. If the vet prefers, an ultrasound can be performed, a more diagnostic and specific digestive test.

If the vet suspects a systemic condition or wants to rule out other diseases, bloodwork can be done. But in this case, if only the hard-then-soft stool condition is being assessed, the tests above are usually enough.

Treatment for Small Intestine Diarrhea

Treatment will involve eliminating and/or treating the cause (though this isn't always possible). It will rest on several pillars:

• Diet: a few hours of intestinal rest, then gradually introducing a bland diet based on either intestinal canned food or boiled rice and chicken, without bones, salt, or spices. It should be given in several small, frequent meals throughout the day.
• Probiotics: additional bacteria that help balance the bacterial flora every mammal has in its intestine. These can be given as daily sachets or paste. They help a lot with intestinal problems.
• Medications: any symptom occurring besides the hard-then-soft stool needs to be treated. For example, if there's vomiting, an anti-emetic such as maropitant will be given.

If there's visceral pain, buscopan can be given, which also slows intestinal motility — which is actually helpful here. Mucosal protectants may be needed, as well as antibiotics if the vet deems it necessary (these should be avoided as a first option).

• Fluid therapy: if there's noticeable dehydration, the vet will decide whether to give intravenous fluids (the most effective way to administer fluids).