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Most of us have heard about the possible adverse effects of mold on humans. But did you know that mold can be harmful to pets as well? Keep reading to find out what some experts say about how mold affects pets. Understanding how harmful it can be can help us to better protect our furry friends.

Dr. Linda Simon, MVB MRCVS, Consulting Veterinarian at FiveBarks.

Food Poisoning or Allergic Reactions

As with humans, mold is not something we want to have around our animals. One of the most common ways our pet dogs can be exposed to mold is when they raid bins and find moldy foods to binge on.

They can develop serious food poisoning and symptoms, including vomiting, diarrhea, fever, tremors, and even seizures. Sadly, [this] can be life-threatening unless prompt vet care is received.

We can protect our dogs from moldy food by ensuring the trash can is well out of reach, ideally behind a locked door. Moldy food should not be put in the yard for wildlife to eat, and we should keep our pets away from moldy food when out on a walk. If you think your dog has ingested mold, bring them to the vet right away so we can induce vomiting.

If a dog were to inhale mold, this is also bad news. It can potentially lead to respiratory distress as well as digestive issues and even allergies. Signs of allergies can include red and itchy skin, runny eyes, and sneezing. In some cases, mold exposure can lead to chronic fungal infection within the dog’s nasal passages.

Try to prevent mold from growing in your home and treat any that is already present. This is not only for your dog’s sake but also for the health of you and your family. Ensure your home is well ventilated and not too damp or humid. Carry out regular maintenance on any A/C units to ensure mold is not forming.

Varying Symptoms

Mold prevention is even more important to our pets because they cannot verbalize their symptoms to us.

Exposure to mold spores causes symptoms such as lethargy, sneezing, irritated lungs and eyes, diarrhea, and much more. In some cases, it can infect open wounds and prevent them from healing, and even cause neurological problems.

Charles Leduc, Chief Operations Officer at Mold Busters.

Alex Crow, A veterinarian who works with HappiestDog.

Serious Ailments

Mold is as harmful to pets as it is to humans and can cause some serious ailments if not treated.

Mold can cause severe respiratory issues in your pets, which will lead to difficulty breathing, coughing, and sneezing.

Mold spores can also become attached to your pet’s fur or skin, leading to skin issues and, if ingested, will cause stomach problems. Other signs your pet may have been exposed to mold include vomiting, sore skin, excessive licking, loss of appetite, and abnormal nasal discharge.

If your pet has become exposed to mold, you will need to find the source and clean away the mold or throw out whatever it is. Bath pet toys, unwashed pet bowls, or expired pet food can be common causes of mold. Always make sure to check your pet’s toys, food, and dishes frequently to prevent them from becoming exposed.

Mild to Severe Reactions

Mold affects animals in similar ways to how it affects humans. Allergic reactions and respiratory infections are the most common problems dogs face when exposed to mold.

If your dog comes into contact with mold, he may experience skin irritation, coughing, sneezing, and a runny nose. Dogs may also exhibit behavior changes such as lethargy, loss of appetite, and even depression after mold exposure.

If your dog inhales mold spores or eats mold, more severe reactions may appear, such as vomiting, diarrhea, seizures, and breathing difficulties. In these cases, you should take him to a vet immediately.

Dogs with compromised immune systems like puppies, older dogs, and overweight dogs are at particular risk for mold-related diseases.

Li-ran Bukovza is the founder of PuppyTip, a dog advice website created to inspire and educate curious dog owners.

Nora Glover, Founder & Editor-in-Chief at Catademy.

Respiratory, Skin, or Gastrointestinal Effects

Like humans, pets can breathe in [mold] spores and experience disturbing effects on the respiratory system, including mold allergies.

Your pets’ coats can also trap the spores and cause skin irritation, as it’s very hard for your pet to get rid of them without help. Finally, your pet may digest mold and experience mild to severe gastrointestinal tract issues.

The most common symptoms include:

  • Sneezing
  • Vomiting
  • Lethargy
  • Rapid breathing
  • Excessive scratching and leaking
  • Skin sores and inflammation
  • Low to no appetite

Toxins and Fungal Infections

Mold is caused by a fungus, an organism that thrives in a moist environment and travels through the air via microscopic spores. Several species of fungus can cause mold that can also affect your pets.

Here are some of the more common:

Mycotoxins: Also known as aflatoxins, mycotoxins are due to a fungus called Aspergillus fungus that can cause mold in dry dibble pet foods that are stored improperly. The mold itself is not toxic; however, it can create toxins that are harmful to pets, causing vomiting, diarrhea, energy loss, and in severe cases, liver poisoning, which can result in severe sickness and yellowing of the skin and eyes (jaundice).

These toxins can occur even in food where there is no visible mold present. There is no evidence that pet owners who handle food contaminated with aflatoxins are at risk; however, it is always good to wash your hands after handling pet food.

Aspergillosis is another mold that can negatively affect pets. Aspergillus mold grows on stored grains, compost piles, dead leaf piles, and decaying vegetation in general. Although many Aspergillus species are harmless, some can cause disease in individuals with weakened immune systems.

Most times, dogs present with nasal signs of aspergillosis, including chronic yellow or green mucus discharge. In some cases, aspergillus can invade other parts of the body and cause symptoms. Symptoms on the part of the body that is affected can include joint pain, fever, weight loss, loss of appetite, inflammation in the eye, or drainage from the affected area (pus).

Candida is considered ‘normal flora,’ i.e., it usually lives in a pet’s gastrointestinal and genitourinary tract. However, if a pet’s immune system is weakened, it can overgrow and cause thrush.

Symptoms depend on what system is affected: if a dog has a candida overgrowth in its mouth, it may result in drooling. If they have a candida overgrowth in their urinary system, it can result in the signs of a UTI. Dogs that have diabetes or hyperadrenocorticism are at increased risk of candida overgrowth. Treatment aims to resolve the underlying cause, if possible and restore the normal balance of flora.

Ringworm is a very contagious mold-like organism that can cause skin issues. Pets can pass it to each other and humans, and ringworm (dermatophytosis of trichophyton species) can also live on fomites (bedding, brushes, etc.). Ringworm usually causes a small, circular, raised, reddened skin lesion that may or may not be itchy. Despite its contagious nature, ringworm is often self-limiting and easy to treat.

Dr. Sarah Wooten, DVM, CVJ, veterinarian on staff at Pumpkin Pet Insurance.

This is a crowdsourced article. Contributors are not necessarily affiliated with this website and their statements do not necessarily reflect the opinion of this website, other people, businesses, or other contributors.