Puppy Parasites: What You Need To Know

Puppy Parasites: What You Need To Know

Puppyhood is an extremely important part of the life of your dog. This period is filled with new experiences, lessons, and emotions as your puppy learns how to behave in the household and in social situations. However, during this phase of their life, puppies are also highly sensitive to hazards and exposed to risks.

Parasites, which are organisms that live in or on a host organism and thrive at its expense, are among the worst - and most common - enemies for puppies. Most newborn dogs require deworming treatments shortly after their birth, as some parasites can be passed on from their mothers’ bodies.

In general, internal (such as intestinal) and external parasites are extremely common in puppies and, if left untreated, can cause severe gastrointestinal, respiratory, and immune system diseases. Here is all you need to know about the most common types of parasites affecting puppies.

Most Common Puppy Parasites

The parasites that can affect your puppy are endless. However, the most common types include:

  • Internal parasites: these puppy parasite types live inside the puppy, unusually in their intestine or bloodstream. Contagion happens through stools, contact with infected livestock, or from the mother’s uterus or milk.
    • Roundworms
    • Hookworms
    • Tapeworms
    • Heartworms
    • Whipworms
    • Giardia
    • Coccidia
  • External parasites: these parasites live on the skin or coat of the dog. Contagion usually happens from contact with an infected dog.
    • Ticks
    • Feas

Here is what you need to know about recognizing the type of parasite affecting your puppy.

Internal Puppy Parasites

There are several types of internal parasites, and the most common distinction is between worm and non-worm parasites. However, all internal parasites thrive by living, feeding, and reproducing in the puppy’s intestine, bloodstream, or other areas within the host body.

Worm Parasites


Roundworms are among the most common intestinal parasites for puppies. These worms are white, firm, and around 3in long. Symptoms of roundworms include vomiting, diarrhea, coughing, and malnourishment. The vet will be able to identify this worm by looking at your dog’s stools. This worm parasite can pass from dogs to children and other puppies.


Hookworms are intestinal worm parasites that feed on the dog’s blood by attaching to the intestinal wall. Puppies usually get from their mother’s milk or by ingesting larvae burrowed into the soil. Diarrhea and weight loss are common symptoms.


Tapeworms are intestinal worm parasites that a puppy might ingest by swallowing the original host, which is usually a flea. Symptoms of tapeworms include diarrhea and weight loss, but you might also see parts of the worms in the dog’s stools or around the anus.


Heartworms are internal parasites that live in the bloodstream and usually access the host from an infected mosquito bite. This type of worm can be extremely dangerous for your puppy because they mature in the heart and grow so long to clog it. Since the worms can affect blood flow and cardiovascular health, an affected puppy will cough, become fatigued with little exercise, and suffer from a lack of appetite. The treatment for heartworm disease is highly effective, but it is hard on your puppy, expensive, and needs to be delivered by a specialized vet.


Whipworms are common worm parasites that your puppy will ingest by sniffing, licking, or ingesting contaminated soil. These worms are ?in long, extremely thin, and they live in the puppy’s intestine. You might find it hard to spot them in stool, but you can become aware of their presence if the stool looks covered in mucus.

Non-Worm Parasites


Giardia is a non-worm, internal, unicellular parasite. Because of these, they are so small as to be invisible to the naked eye. Your puppy might contract Giardia from contaminated food, water, or the mother’s body. An infected puppy will suffer from strong diarrhea, which can lead to weight loss and malnutrition. It can be detected through a stool sample.


Coccidia is microscopic, unicellular parasites that are invisible to the naked eye. They are spread from infected soil or from one dog to another. Symptoms of Coccidia infestation include bloody diarrhea, which in severe cases can be a life-threatening condition for your puppy.

External Puppy Parasites

External parasites live on the coat or skin of your puppy. There are several external parasites, including ticks, fleas, lice, and mites. They can lead to poor coat appearance, skin irritation, and, in severe cases, severe diseases. Preventive checkups and regular coat checks (especially if your dog spends time outdoors) are vital - ask your vet how to check for these parasites.


There are over 800 species of ticks, and they feed on the blood of your pet. Ticks can lead to several diseases, including Lyme disease and Rocky Mountain Spotted Fever.


Fleas are among the most common external parasites for puppies. They can irritate the skin and cause the dog to continue scratching the coat and skin. During your daily checks, look out for dark, wingless insects on the dog’s skin.

Signs and Symptoms of Parasites in Puppies

Puppy parasite symptoms depend on the kind of parasite. The most common symptoms of internal worms include:

  • Diarrhea
  • Vomiting
  • Pot-bellied
  • Lethargy and fatigue
  • Abdominal pain
  • Weight loss
  • Dehydration
  • Deficiencies and malnutrition
  • anemia
  • Intestinal blockage
  • Blood in stool

Heartworms, which severely affect the cardiovascular system, also cause coughing, respiratory issues, weak pulse, weight loss, and death.

External parasites might cause different symptoms, such as:

  • Excessive licking
  • Scratching and itching
  • Biting
  • Loss of hair
  • Red, bumpy bites
  • Red patches on the skin
  • Bacterial infections
  • Skin infections
  • Poor coat appearance

Puppy parasite treatments always depend on the parasite, and they need to be administered immediately. So, as soon as you notice differences in behavior or health, get in touch with your vet immediately.

Tips: Preventing, Diagnosing, and Treating Puppy Parasites

The most common parasites to look out for include roundworms, giardia, coccidia, and hookworms. Your geographical location and living condition of the puppy can increase exposure to certain parasites. Some factors that can influence the presence of parasites include:

  • Exposure to livestock
  • Weather
  • Geographical locations
  • Wild animals
  • Living conditions

A local vet can help you identify the most common parasites in your area. At the same time, you can reduce the risk of your puppy contracting a parasite by:

  • Keeping your outside area clean
  • Removing faces as fast and quickly as possible
  • Clean up the stools, hair, and dirt left by other animals
  • Keep your dog’s bowl clean
  • Make fresh water available at all times (to avoid your puppy drinking from puddles)

You should also lookout for telltale signs of infestation. Some of the aspects to consider include:

  • Your puppy’s stools
  • Your puppy’s appetite, food intake, and eating habits
  • Behavioral changes

Parasites can be life-threatening if left untreated - but there are effective medical treatments that can help your puppy avoid most side effects. Speak to your vet and be prepared to spot a parasite infestation before it starts to affect your dog.

Keeping Your Puppy Healthy and Happy

Puppies are more prone to parasite infestation, which might be caused by their lifestyle, living conditions, geographical location, or nursing. However, your puppy can live a happy and fulfilling life while also not running severe risks. All you need to do is look out for their health, provide them clean and suitable living conditions, and train yourself to recognize the early signs of parasites.

Health Disclaimer: This post is educational in nature and doesn’t constitute health advice. Please consult your pet's veterinarian or other healthcare professionals for specific guidance on this topic.

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