Cats Wiki

Welcome to the Cats Wiki! Hope you enjoy learning and contributing here; but before you start doing that, please do read our Guidelines before you start providing constructive edits and to play it safe with the community.

Best wishes, The Cats Wiki Administrators.


Cats Wiki
Toxocara cati in cats

A cat being checked as if having Toxocara cati.

Toxocara cati, also known as the feline roundworm, is a parasite of cats and other felids. It is one of the most common nematodes of cats, infecting both wild and domestic felids worldwide. Adult worms are localised in the gut of the host. In adult cats, the infection – which is called toxocariasis – is usually asymptomatic. However, massive infection in juvenile cats can be fatal. Feline roundworms are brownish-yellow to cream-colored to pink and may be up to 10 cm in length. Adults have short, wide cervical alae giving their anterior ends the distinct appearance of an arrow (hence their name, toxo, meaning arrow, and cara, meaning head). Eggs are pitted ovals with a width of 65 μm and a length of about 75 μm making them invisible to the human eye. The larvae are so small that they are easily transmitted from an adult female to her nursing kittens through her milk.

Wild felids can become infected from a variety of sources; the primary source is infected fecal matter. The eggs of the roundworm become infective in three to four weeks after being passed out in fecal matter. Contact with the soil, licking fur near feet, and eating a host animal (such as rodents) can also lead to infection of the felines. The consumption of infected carrion also leads to contraction of the parasites, which is some of the food that members of Felidae consume. The eggs hatch in the intestines and the larvae are then released into the cat's digestive tract. The larvae are capable of migrating through the tissues and are found in the liver, lungs, tracheal washings and muscles as well as in the digestive tract. From there, they move up to the trachea where they are swallowed, causing hacking and other problems. The larvae can also move throughout the body and cause more damage to the infected individuals. The worms can even go into the mother's milk and infect the young.

There are numerous clinical signs when dealing with feline roundworm. Some clinical signs that can be detected easily are:

  • Vomiting
  • Decreased appetite
  • Poor growth
  • Changes in behavior
  • Excessive fatigue
  • Wheezing or breathing difficulties
  • Skin rashes
  • Seizures, fits, tantrums
  • Blurred or cloudy vision. usually only affecting one eye
  • A very red and painful eye
  • Swollen patches of fur

Additional clinical signs that can be identified include:

  • A pot bellied appearance
  • Abdominal discomfort
  • Diarrhea

Treatment for Toxocara cati infections in cats is rather simple. There are a number of anthelmintics that will kill the adult worms, including Ivermectin, emodepside, fenbendazole, milbemycin, and moxidectin. However, most drugs are ineffective against the immature parasites. Consequently, infected cats will usually need multiple doses administered in two or three week intervals in order to fully eradicate the worms.

See also[]


view · talk · edit Cat Health
Contents Cancer in CatsCat AgeCat FleaCat HealthCat PheromoneCat Skin DisordersDiabetes in CatsDirofilaria ImmitisFeline AcneFeline AsthmaFeline CalicivirusFeline CoronavirusFeline Cutaneous AstheniaFeline CystitisFeline Hepatic LipidosisFeline Hip ReplacementFeline Hyperesthesia SyndromeFeline Hypertrophic CardiomyopathyFeline Immunodeficiency VirusFeline Infectious AnemiaFeline Infectious PeritonitisFeline Leukemia VirusFeline Lower Urinary Tract DiseaseFeline Odontoclastic Resorptive LesionFeline PanleukopeniaFeline Spongiform EncephalopathyFeline VaccinationFeline Viral RhinotracheitisFlea ControlFlehmen ResponseHigh-Rise SyndromeNeuteringOnychectomyPolydactyl CatRabiesRingwormSeizuresSpayingTickToxocara catiToxoplasmosis
Cat Health CategoriesPortal