Your dog’s poo can tell you a lot about their health and wellbeing. While nobody would expect dog poo to smell particularly pleasant, if it has a really bad smell it might be a sign that something’s not quite right. In this guide, I’ll explain why dog poo can have a strong odour, as well as how to tell when the smell might be a cause for concern. I’ll also give my tips as a nutritionist on how you can protect your dog’s digestive health with the right food for them – which should also help reduce the odour.
Key takeaways
- Very strong-smelling dog poo, especially when accompanied by an upset stomach, can mean your dog has eaten something that doesn’t agree with them or point to an issue with their digestive health.
- Switching food too suddenly, food allergies and intolerances, eating something that’s too rich or scavenging for rubbish can all be a factor.
- If food isn’t the issue, strong-smelling poo might be the result of a bacterial or viral infection, worms or stress. Although less common, dogs may also have a gastrointestinal illness like IBD.
- Healthy dog poo has a firm consistency and shouldn’t smell particularly strong. Shades of brown including reddish brown and greenish brown are all normal, but pale, yellow or black poo might all be a sign of an issue with your dog’s digestive health.
- Keep an eye on any changes in the colour, consistency, smell, frequency or volume of your dog’s bowel movements – if you pass on this information to your vet (along with a sample if they request this) they’ll be able to identify any health issues that might be causing this.
- Choosing the right dog food can help improve your dog’s digestive health and therefore the health of their poos. Look for gut-friendly ingredients like prebiotics and fibre, but bear in mind that all dogs are different, so a one-size-fits-all approach won’t work as well as finding out what food is ideal for your dog.
Table of contents
What causes smelly dog poop?
What healthy dog poo should look and smell like
Smelly watery diarrhoea in dogs
Smelly dog poop with mucus
Black and smelly dog poop
How to make dog poop less stinky
How diet affects smelly dog poop
When to speak to your vet
What causes smelly dog poop?
There are several different reasons why dog poo can have such a strong smell, but in short it’s usually down to either your dog’s diet or their digestion. If food isn’t digested properly, it ferments in the gut, producing gas – as well as leading to uncomfortable symptoms like stomach pain. Let’s break down these potential reasons for smelly dog poo into a bit more detail.
Diet and food quality
If your dog has eaten something that’s not easy to digest for some reason, this can give them an upset stomach and lead to unhealthy poos. This could range from scraps of human food (especially if it’s rich and high in fat) to something out of the rubbish or even dog poo or poo from other animals. Basically anything that your dog shouldn’t really eat could give them gas, diarrhoea and other symptoms of an upset stomach, which is why it’s so important to try and gently distract them from sneaking a bite of these things.
Sudden diet changes
Switching your dog’s food too quickly can also upset their digestive system, leading to diarrhoea. If you’re changing your dog’s diet, it’s best to do it gradually as explained in our guide to changing dog food. Gradually, add a little bit more of the new food into your dog’s old food over the course of about a week, until they’re totally switched over. This will give your dog’s gut microbiome time to adjust to new ingredients. [1]
Food intolerance or sensitivity
The food you’re giving your pet might be fine for most dogs, but there might be an ingredient used that your dog is allergic to, or has an intolerance or sensitivity to. True allergies are rarer than other kinds of reactions, and are usually a response to proteins. [2] However, dogs can have a sensitivity to different kinds of ingredients or nutrients. They might be sensitive to certain kinds of fibre, or the level of fibre or fat in their food. You can read more about this in our recent article about food intolerances and sensitivities.
Digestive upset or illness
Usually diarrhoea and unhealthy poos are a reaction to something your dog has eaten, but in some cases it might be less about your dog’s diet and more about their digestive system. [3]
- Parasites like worms can irritate your dog’s gut, giving them an upset stomach. While dogs of any age can be affected by worms, younger puppies are more vulnerable, which is why they need to be given worming treatment more often than adult dogs.
- Bacterial or viral infections can also cause diarrhoea and poo that smells worse than usual. Making sure your dog is up to date with all their vaccinations will help protect them from catching these diseases, some of which can be dangerous, such as canine parvovirus. [4]
- Inflammatory disorders such as IBD can affect dogs as well as people, and can cause symptoms like diarrhoea, vomiting or weight loss. If your dog is diagnosed with one of these conditions, your vet might recommend a special diet that doesn’t irritate their digestive system.
Your dog’s gut microbiome also plays an important role in their digestive health. Good bacteria help your dog break down different ingredients, but when they are outnumbered by unhealthy bacteria, it can lead to symptoms like an upset stomach.
Stress
Diarrhoea, gas and other gastrointestinal symptoms can also all be the result of stress or anxiety, just like in us humans – in dogs, it’s known as ‘stress colitis’. Some common causes might include moving house, changes to your dog’s routine such as travelling, or being introduced to a new pet or baby in the family. Events that cause loud noises like fireworks and thunderstorms can also have this effect.
Lastly, as well as anxiety and stress, excitement could be the cause – for instance, if your pet has had a really busy and fun day at the dog park, they might get a bit overwhelmed and react with an upset stomach.
What healthy dog poo should look and smell like
Here’s what to look out for to know whether your dog’s poo is healthy. Remember, all dog poo will have a bit of a smell, but an unusually strong odour could be a sign of a digestive issue. I’ve also explained some potential reasons for changes to your dog’s poo and what each could indicate about their health.
Healthy poo:
- Consistency: The ideal poo is log-shaped and firm, but not too solid. It should be easy to pick it up and throw it away. There may be some mucus but you shouldn’t see a lot or see it often.
- Colour: The colour of your dog’s poo depends a lot on your dog’s diet. Only you know what is normal for your dog. Shades of greenish brown, red brown or dark brown are all normal.
- Odour: Dog poo should have a mild odour; any dramatic changes can indicate problems. It’s always going to smell somewhat, but with a good diet your dog’s poos should be bearable.
- Frequency: Most dogs poo around twice a day, but this can depend on their feeding schedule. They might also poo three times a day. Puppies tend to poo more frequently because they eat more regularly.
Unhealthy poo:
- Consistency: When diarrhoea or loose, runny poo occurs, this can result from many different causes. If your dog’s poo is too hard, this can cause constipation. If your dog is constipated this could be due to a lack of water or fibre in their diet, or a case of worms. While some mucus is normal, if you often see it or you can see a lot of it in your dog’s poo, it can be a sign that their colon is irritated.
- Colour: Abnormal colours like dark black tarry substances could indicate internal bleeding and digested blood in the stool. Pale, yellowy or greasy poo can indicate fat digestion issues with the pancreas, or malabsorption, a condition where your dog can’t absorb fat. Any dramatic changes in colour or visible blood is a cause for concern. In this case, always see your vet and take a stool sample with you.
- Odour: Flatulence or a particularly stinky poo could signal a change in your dog’s gut microbiome, or they’re struggling to cope with a new diet or ingredient. Treats and human foods are common culprits.
- Frequency: If your dog poos more than three times a day, this could signal there’s something not right with their diet. In some cases, it might mean they’re eating more than they need. (At Tails.com, we’ll work out exactly how much food your dog needs so you don’t need to worry about under or overfeeding.) Equally, if your dog has a food intolerance, this can also make them poo more often. If your dog doesn’t poo every day or only once a day, they could be constipated. Always consider what’s normal for your dog.
- Volume: Sudden larger or smaller poos can be a sign of health problems. Huge volumes of poo can mean your dog isn’t digesting their food properly, or their diet is high in fibre. Low volumes could indicate gastrointestinal problems or even a blockage. If it’s out of the ordinary, you should always get your dog checked over by a vet.
If your dog has experienced any changes after switching to Tails.com food, get in touch and our team will be happy to help.
Smelly watery diarrhoea in dogs
Watery, bad-smelling diarrhoea is often a sign of digestive upset, and it can happen as a result of quite a lot of different reasons. It usually passes quickly, but if your dog has severe, watery diarrhoea that lasts longer than 24-48 hours, you should call your vet. If it’s accompanied by symptoms including vomiting, lethargy and loss of appetite or you can see blood in the diarrhoea, it’s especially important to get in touch with your vet.
Diarrhoea can be a result of dietary factors such as dietary indiscretion (eating something outside of their normal diet) or a sudden change in their diet, for instance if they have been switched suddenly to a new food. It can also be a symptom of a food intolerance, sensitivity or allergy.
Watery poos can also be a symptom of parasites, or bacterial or viral infections. These issues can be more serious than a simple case of dietary indiscretion, which is why it’s so important to get in touch with your vet to help get a diagnosis for your dog.
Runny poop and smelly farts
If your dog’s poo is a bit watery and you’ve also noticed flatulence, this may be the result of food fermenting in their gut that hasn’t been fully digested. Whether it’s an ingredient their body isn’t able to digest due to an intolerance, or they’ve scavenged some rubbish from the bin, it can suggest that bacteria in the gut are breaking something down and causing it to ferment.
If your dog is gassy but it’s not accompanied by unhealthy poos, there’s a chance they might simply be eating too fast and swallowing air. Some dogs just have a lot of enthusiasm when it comes to dinnertime – in this case, a slow feeder or puzzle feeder might help calm their stomachs.
Soft or loose stools
Soft or loose dog poo might have a stronger smell for several reasons. The dog might have unhealthy bowel movements as a result of an infection, which has forced the food to move through the gut too quickly, or changed the breakdown of bacteria in the gut. A health condition might be causing malabsorption, leaving some nutrients to ferment rather than being digested, but a food intolerance could also mean some ingredients aren’t being digested.
Causes for soft, bad-smelling poos can include dietary changes, excess fat or fibre in the diet, a sensitive stomach or stress. If the issue is dietary, finding out exactly which ingredients or macronutrients are negatively affecting your dog can help soothe their stomach. They may need a specialist diet – we make sensitive stomach dog food that’s formulated to be easy to digest and gentle on the stomach.
Smelly puppy poop and puppy farts
It’s not adult dogs who can produce some terrible smells – even a tiny puppy can clear a room. This isn’t necessarily something to worry about, but here are some reasons why this may be, along with some ways to help keep your growing puppy feeling comfortable from top to belly to tail.
Your puppy might be responding to the transition from puppy food to adult dog food, and it could be a sign that you need to slow down the process of switching their food. At Tails.com, our Adaptive Nutrition system does this automatically – we’ve designed it to make the transition slow and gradual to lower the chance of a reaction like this. However, if you notice your puppy having digestive issues, just let us know and we can slow down the switch and look into which ingredients are included in their blend.
Your puppy might have quite a sensitive stomach, especially if they’re only very young – their digestive system will still be developing. We’ve got lots more information here about puppy nutrition in my recent blog post on the subject. As well paying attention to what ingredients they’re eating, it might help to watch out to make sure they’re not eating too much, as overeating can cause diarrhoea, gas and other digestive problems.Lastly, this is just a reminder to make sure your puppy stays up to date with their vaccinations and worming treatments. We’ve briefly discussed parasites in this article, which can be a cause of digestive issues in dogs of any age. But they are much more dangerous for little pups, whose immune systems aren’t as strong and who are more vulnerable to dehydration. [5]
Smelly dog poop with mucus
Mucus in dog poo usually looks like clear jelly or slime. Some mucus in dog poo isn’t a cause for concern, especially if you only notice a bit of it or if you don’t see it often. However, if you see lots of mucus in your dog’s poo or you see it frequently, it can be a sign that your dog is experiencing intestinal irritation. [6]
This irritation could be caused by a few different things, including an inflammatory condition like IBD – an overreaction from the immune system that causes inflammation in the gut, which affects their digestion. Their gut might also be irritated by a food intolerance, allergy or sensitivity, or by having eaten something else that doesn’t agree with them – in some cases not even food. Lastly, an infection of some kind (whether that’s bacterial, viral or parasitic) can also cause gut irritation.
In all these cases, the dog’s body responds to the irritation by producing more mucus to protect the intestinal walls, which leaves the body along with their poo.
Black and smelly dog poop
Black dog poo means that there is partially digested blood in your dog’s poo [7]. This can indicate an internal injury, but may also mean they have swallowed blood – for instance if they have recently eaten food or treats that include organ meats. In some cases it can be a side-effect of medications.
Generally speaking, if you notice this, we’d recommend contacting your vet to arrange a check up, especially if your dog also seems lethargic or uninterested in food, or if your dog has persistent black poo. If you see red blood in your dog’s poo, always contact your vet in this instance too – it might not be serious, but it could be a sign of a medical issue.
How to make dog poop less stinky
Of course, we can’t expect dog poo to smell very nice – it’s poo after all. However, if you’ve noticed your dog’s poo smells worse recently (or worse than that of other dogs) there are a few things you can do that should help tone down that smell, and make your dog more comfortable. Strong smelling dog poo can be a sign that something isn’t quite right with your dog’s digestive system, or that their food doesn’t agree with them.
- Introduce any dietary changes gradually: Switching food too suddenly is a key reason for upset stomachs in dogs. If you’ve recently changed your dog’s diet, strong-smelling poos and diarrhoea may be a sign that the switch was a bit too fast.
- Stick to a routine: All dogs benefit from a routine, but dogs with a sensitive stomach might benefit even more. Regular meal times lead to regular bowel movements, making it easier for you to keep an eye on your dog’s digestive health.
- Don’t give too many treats: Too many treats might give your dog gas or an upset stomach – they can be rich and high in fat, a nutrient that can have a negative effect on dogs’ digestive health, especially those with sensitive stomachs. Even low-fat treats should be given in moderation, as part of a healthy diet.
- Look for gut-friendly ingredients: If your dog has unusually smelly poos, they might benefit from a food with lots of gut-friendly ingredients. This might be a food that’s formulated for sensitive stomachs. It might also be the case that your dog reacts to certain ingredients or nutrients, meaning that they need a food that avoids these.
- Make sure your dog gets enough fresh water: Water supports healthy digestion, so making sure your dog stays hydrated is really important. You should also clean your dog’s water bowl and top it up with fresh water frequently – bacteria in the water can make your dog poorly.
How diet affects smelly dog poop
Of course, we can’t expect dog poo to smell very nice – it’s poo after all. However, if you’ve noticed your dog’s poo smells worse recently (or worse than that of other dogs) there are a few things you can do that should help tone down that smell, and make your dog more comfortable. Strong smelling dog poo can be a sign that something isn’t quite right with your dog’s digestive system, or that their food doesn’t agree with them.
- Introduce any dietary changes gradually: Switching food too suddenly is a key reason for upset stomachs in dogs. If you’ve recently changed your dog’s diet, strong-smelling poos and diarrhoea may be a sign that the switch was a bit too fast.
- Stick to a routine: All dogs benefit from a routine, but dogs with a sensitive stomach might benefit even more. Regular meal times lead to regular bowel movements, making it easier for you to keep an eye on your dog’s digestive health.
- Don’t give too many treats: Too many treats might give your dog gas or an upset stomach – they can be rich and high in fat, a nutrient that can have a negative effect on dogs’ digestive health, especially those with sensitive stomachs. Even low-fat treats should be given in moderation, as part of a healthy diet.
- Look for gut-friendly ingredients: If your dog has unusually smelly poos, they might benefit from a food with lots of gut-friendly ingredients. This might be a food that’s formulated for sensitive stomachs. It might also be the case that your dog reacts to certain ingredients or nutrients, meaning that they need a food that avoids these.
- Make sure your dog gets enough fresh water: Water supports healthy digestion, so making sure your dog stays hydrated is really important. You should also clean your dog’s water bowl and top it up with fresh water frequently – bacteria in the water can make your dog poorly.
H2: How diet affects smelly dog poop
There are many ways your dog’s diet can influence their digestive health and therefore their bowel movements – the table below breaks down how each of these factors plays a role.
| Dietary factor | Effect on digestive health and bowel movements |
| Digestibility of ingredients | How ‘digestible’ food is means how easy it is for the stomach to extract the nutrients. A diet that’s full of ingredients that are hard to digest means your dog will need to eat more in order to get the nutrients they need, and they will also likely produce more poo, because they’re absorbing less food. In contrast, people often find that when they give their dog a highly digestible diet, it leads to smaller poos and a higher stool quality overall. |
| Protein quality | High-quality protein, that’s easy to digest and contains the amino acids dogs need, can really help support digestive health. We use healthy, tasty protein sources like beef, chicken, lamb and salmon in our kibble blends and wet food. |
| Fibre balance | Fibre can help add bulk and substance to your dog’s poo. Every dog is different and the level of fibre that’s right for your dog might vary. Some dogs thrive on a high-fibre diet, while others need a low-fibre diet – too much fibre can cause an upset stomach. |
| Fat balance | Some dogs are very sensitive to fat and really benefit from a low-fat diet for their digestive health. This is especially true for dogs with pancreatitis, a condition that means they need to limit dietary fat. |
| Gut microbiome health | There are some ingredients that are especially helpful for supporting a healthy gut microbiome. Prebiotics are a type of fibre that help create a good environment for healthy bacteria, which aid digestion and support the immune system. As well as including prebiotics in our food, here at Tails.com we also have supplements including probiotics (the ‘good’ bacteria themselves). |
Best dog food for less smelly poop
So what does this mean when selecting the right diet for your dog? There are a few routes to go down, and you can also use these tactics in combination – for instance, if you suspect your dog is allergic or sensitive to certain ingredients, and you and your vet also want to increase their fibre intake.
- Highly digestible proteins: Protein is a really important macronutrient for dogs, and choosing food that has protein that’s easy to digest will be very beneficial for their digestive health.
- Balanced fibre: Increasing dietary fibre can help improve stool quality – soluble fibre absorbs water to firm up poos, while insoluble fibre adds bulk. It also helps promote regular bowel movements and reduce constipation. However, bear in mind that dogs with some medical conditions may need a low-fibre diet, such as dogs with IBD – your vet will advise you what level of fibre is right for your dog.
- Limited ingredient or hypoallergenic diet: If your dog is sensitive or allergic to certain ingredients, it might help to give them a limited ingredient diet, to reduce the number of things they’re being exposed to which could cause a reaction. [8] Or perhaps a hypoallergenic diet might be a good way to go, which cuts out beef, dairy, wheat, soya and egg, the most common allergens. Our range of hypoallergenic dog food includes wet food and delicious treats, and won’t leave your dog feeling like they’re missing out on anything.
When to speak to your vet
If your dog’s poo is a bit stinky that’s not necessarily a cause for concern by itself. But if it continues for several days, or you notice that it’s accompanied by any of the following symptoms, it could be a sign of a health issue.
- Persistent diarrhoea (lasting more than 24-48 hours)
- Blood in poo
- Black poo
- Lethargy
- Vomiting
- Dehydration
- Weight loss
A trip to the vet can set your mind at ease, and they’ll be able to diagnose and treat your dog if they do turn out to have any health issues. Don’t feel embarrassed about contacting your vet to say that your dog’s poo smells worse than usual – they get calls about this kind of thing all the time. Keeping an eye on your dog’s bowel movements is a key part of being alert to any changes in their health, along with their eating or drinking habits and their energy levels. [9]
Conclusion: Improving your dog’s digestive health
your dog’s poos usually have a very strong smell, it might be a sign that their digestive health needs a little support, or that their diet may not be right for them. In some cases, it can also be a sign of a medical issue that needs veterinary support.
Bad-smelling dog poo can be the result of a dietary intolerance or allergy, a sudden change in diet, a bacterial or viral infection, worms or stress, among other factors. It’s often part of diarrhoea or an upset stomach. Figuring out what’s causing your dog’s smelly poos may well be the first step to helping improve their digestive health and making them feel more comfortable.
FAQs:
What food helps reduce smelly dog poop?
The first step might be cutting out any ingredients that your dog is allergic or sensitive to – smelly poos can be the result of ingredients fermenting in the gut because they haven’t been digested correctly. Other factors include the breakdown of macronutrients in your dog’s food like fat or fibre – different dogs’ reactions to these might vary. However, most dogs benefit from the addition of healthy fibre and prebiotics to their diet, bulking out their bowel movements and supporting the good bacteria that live in the gut.
When should I worry about smelly dog poop?
Bad-smelling dog poo can be a warning sign if the odour has become stronger or if it’s much worse than other dogs’. Diarrhoea that continues more than 24-48 hours can be a cause for concern as it puts dogs at risk of dehydration. A dramatic change in colour can be another indication that you should call the vet, for instance if the poo is pale, yellow, black or contains red blood. Worms can make dog poo smell worse, and if you see any kind of parasites in your dog’s poo, you should also contact your vet to arrange treatment.
Sources
[1] ‘Longitudinal fecal microbiome and metabolite data demonstrate rapid shifts and subsequent stabilization after an abrupt dietary change in healthy adult dogs’, Animal Microbiome, 1 August 2022
[2] ‘Food allergies in dogs’, PDSA
[3] ‘Vomiting and diarrhoea in dogs’, Blue Cross
[4] ‘Parvovirus: symptoms, treatment, and prevention’, Dogs Trust
[5] ‘Worms in dogs’, PDSA
[6] ‘Mucus in dog poop’, PetMD, 31 January 2024
[7] ‘Blood in dog poo’, Blue Cross
[8] ‘What is a limited ingredient dog food?’, PetMD, 8 January 2021
[9] ‘When to take your dog to the vet’, Dogs Trust