Toxocara in dogs is an intestinal parasite, primarily located in the small intestine. This parasite, known as Toxocara canis, can cause symptoms such as diarrhea and weight loss. Recognizing the signs of this intestinal parasite is crucial for prompt and effective treatment.
Clinical Signs
Often, dogs infected with Toxocara show no obvious symptoms. However, common signs include diarrhea, occasionally accompanied by vomiting. Adult worms may sometimes be expelled, though this isn’t always the case. Dogs might also lose weight despite having a normal or increased appetite.
In severe infestations, worms can cause intestinal obstruction, potentially leading to perforation in extreme cases.
Lifecycle of Toxocara
Adult worms lay eggs that are excreted in the dog’s feces. Under favorable conditions, these eggs develop into infectious larvae in about four weeks. When a dog ingests these eggs, larvae hatch in the stomach or intestine, then migrate to the lungs to mature. From the lungs, larvae travel up the windpipe, are coughed up, and then swallowed again. Once back in the small intestine, larvae mature into adults and lay new eggs, completing the lifecycle.
The total duration of this cycle is about one month, but eggs can survive up to five years in the environment.
Transmission
Toxocara can spread in several ways:
- By ingesting eggs present in the environment
- Via transplacental transmission (most common in dogs)
- Through the ingestion of maternal milk
- By consuming a paratenic host, such as mice or rats. A paratenic host harbors the parasite in a dormant stage without actively contributing to its lifecycle.
Is Toxocara Contagious to Humans?
Yes, humans can be infected by ingesting Toxocara eggs found in the environment. However, since humans are not natural hosts, larval migration is erratic. Larvae may settle in various organs, including the retina, potentially causing vision problems or even blindness.
Diagnosis
Diagnosis involves identifying adult worms in the dog’s intestine. If worms aren’t visible, stool samples are microscopically examined for eggs. These eggs are slightly oval-shaped, with a thick double wall—dark inner and lighter outer layers. As egg shedding can be irregular, multiple tests might be necessary.
Treatment
Safe and effective antiparasitic medications are available by prescription to treat this infection.
Prevention
To prevent infection, promptly removing dog feces is crucial to prevent eggs from becoming infectious. Wear gloves when handling feces and wash your hands thoroughly afterward. Vegetables from gardens should also be carefully cleaned before consumption.
Additionally, preventive antiparasitic treatment is recommended monthly from spring to fall for all dogs.
For personalized advice on suitable treatments for your dog, feel free to consult our veterinary team.
