During your initial visit to the veterinarian with your puppy or kitten you may start to feel a little overwhelmed by the abundance of information you receive on vaccines, de-worming, spaying or neutering and overall preventive care. In this series of posts, I hope to provide a comprehensive summary of all the essential veterinary information you may receive and why it’s so important!
Deworming is often the first treatment your puppy or kitten will receive. Its importance lies not only in the implications for your pet’s health but also in its relevance to public health.
It is natural to wonder why puppies or kittens need to be wormed so soon after birth, especially when their exposure to the outside world has been so limited. Most pet owners are unaware that the mother is actually the first source of parasitic infection for puppies and kittens. Many puppies are born with internal parasites due to maternal transfer across the placenta. In both puppies and kittens, infection can also be transmitted via the mother’s milk for the first few weeks of lactation. Even worming the mother throughout the final 3 months of pregnancy is not 100% effective at eliminating transmission to the kittens or pups. The other routes of transmission include ingestion of infective larvae/eggs from the environment or penetration of the skin in the case of hookworms.
Puppies or kittens with worms may exhibit no clinical signs at all or one or more of the following:
- failure to thrive
- poor coat condition
- pot-belly appearance
- anemia (hookworm)
In prenatal roundworm infections in puppies, larvae migrate from the placenta to the lungs of the fetus before being coughed up and swallowed shortly after birth. Consequently puppies may also show respiratory signs such as coughing, an increased respiration rate, and pneumonia in heavy infestations.
Worms are not only a threat to your puppy or kitten but are also a public health concern. Humans become infected with roundworms through ingestion of infective eggs. These eggs hatch into larvae, which can migrate anywhere in the body and cause damage along the way, a condition referred to as Visceral Larva Migrans. Severe infections can cause permanent eye injury, heart or kidney disease, pneumonia or brain damage. Infection is more of a concern in children and the immunocompromised. Children are often in close contact with pets and play in areas prone to contamination such as yards and play areas (eg. sand boxes). People can also become infected with hookworm through ingestion of infective larve or through direct skin penetration. Larvae migrating through the skin cause Cutaeous Larva Migrans, a skin condition characterized by red, intensely itchy lesions. For Information on how to protect your pet and family from parasitic infection visit http://www.petsandparasites.org, a website developed by the The Companion Animal Parasite Council (CAPC).
Ideally, puppies and kittens should be de-wormed every 2 weeks starting at 2 weeks of age until they are 12 weeks of age, then once monthly until they are 6 months old. There are several different products licensed for use in puppies and kittens – your veterinarian can advise you on the product most suited to your pet. These products cover the most common intestinal worms – namely roundworms, hookworms and whipworms. Between 12 and 16 weeks of age, a fecal sample from your pet should be submitted for testing to ensure effective deworming and to detect the less common microscopic parasites giardia and coccidia. These parasites, as well as tapeworms, will require alternative treatment. Tapeworms are transmitted by fleas and mice. Dried up tapeworm segments are visible in your pet’s stool or around the anus, resembling grains of rice.
Clients often question the frequency of worming in puppies and kittens. The Centre for Disease Control and Prevention (CDC) recommends starting treatment at 2 weeks of age in order to prevent widespread contamination of the pet’s environment with eggs. These eggs can remain viable for months to years, serving as a reservoir for future infection. Furthermore, these eggs are zoonotic, which means they are transmissible to people. Adult hookworms and roundworms in the intestines can begin producing eggs when your puppy or kitten is between 2-3 weeks of age. Therefore, de-worming at 2 weeks should eliminate the adults before any eggs are shed – allowing us to prevent rather than treat an infestation. The life cycles of these worms are between 2 – 3 weeks, therefore, de-worming at 2-week intervals ensures that any adults are eliminated prior to the shedding of infective eggs.
Dogs and cats of any age may become infected with intestinal parasites so routine prevention is important. We currently recommend performing at least 1-2 fecal tests per year in conjunction with administration of a broad-spectrum heartworm preventative medication throughout the mosquito season (typically from June to mid-October in Ontario) which will cover the most common intestinal parasites. Ideally families with small children should deworm year round – monthly from spring to autumn and twice over the winter months.