Neospora caninum

The neosporosis is caused by the protozoan Neospora caninum infection in domestic and wild animals. It occurs mainly in domestic dogs and can these trigger a neurological disorder that manifests itself primarily as a brainstem syndrome. When domestic cattle of the excitation abortions triggers.

Pathogen

Neospora caninum is a protozoan and occurs worldwide. It is similar in its morphological forms and the reproductive cycle ( with sporogony, schizogony and gamogony ) Toxoplasma gondii, the causative agent of toxoplasmosis. Both pathogens are morphologically distinguishable only by electron microscopy. The main host and currently only known definitive host for Neospora caninum is the dog (Latin: canis = dog). Both pathogens are distinguished as separate species only since 1988.

Infected dogs differ in their droppings few unsporulierte, about 10 microns wide oocysts from. This sporulate within 3 days in the outside world and are thus infectious. This sporulated oocysts are taken up by intermediate hosts through food and water. As intermediate hosts act cattle, sheep, goats, horses, etc., or even dogs themselves in the intermediate hosts is about 0.1 mm form large tissue cysts. They occur mainly in the nervous tissue, more rarely in the muscles. From these tachyzoites and bradyzoites develop.

Dogs become infected through the intake of raw animal products (brain, meat). In the intestine of the dog, the cysts are released during digestion and begin to multiply. Tachyzoites are found in the brain, spinal cord, pancreas, skeletal muscle, skin, liver and lungs. Cysts, arising only from the bradyzoites develop only in the nervous tissue.

Neosporosis in dogs

Dogs are commonly infected in Europe, but the infection rarely causes a disease forth, but usually progresses latently without clinical symptoms.

Diseases

A serious disease manifests primarily as encephalitis of the brain stem with the formation of a brainstem syndrome ( protozoal meningoencephalitis ). They embark on paralysis of the posterior cranial nerves on (especially facial palsy ), failures of the upper motor neuron (tremor, ataxia, paresis ) and head tilt postures ( torticollis ).

Further syndromes by Neosporosa caninum in dogs are polyneuritis, polymyositis, liver inflammation ( hepatitis), pneumonia (pneumonia) and ulcerative dermatitis.

Diagnostics

In the cerebrospinal fluid - punctate, a pleocytosis be detected with eosinophilic granulocytes.

A determination of the antibody can be performed by immunofluorescence or ELISA, also a direct detection of pathogens by PCR in the feces. However, this evidence only occupy an infection, a causal relationship to the observed disease does not exist.

In the neurological form of the differential diagnosis, a number of other brain stem infections such as distemper, rabies, Aujeszky's disease and toxoplasmosis, and idiopathic granulomatous meningoencephalitis and poisoning must be excluded ( see also VETAMIN D).

Therapy

Neosporosa caninum is sensitive to a range of antibiotics. Can be used clindamycin or combinations of pyrimethamine or trimethoprim with sulfonamides.

Neosporosis in cattle

In cattle play an economic role by Neospora caninum -induced abortions. They were first described in 1989.

When recording of oocysts or outbreak of a latent infection in the mother animal pathogens can cross the placental barrier and lead to an infection of the brain of the fetus. Even during pregnancy can lead to fetal infection. The fetus may die and may cause abortion. In some regions of the U.S. Neospora caninum is blamed for 45% of abortions and therefore has led to a considerable stir.

The significance of Neospora caninum abortion as a trigger in Europe is so far unclear. Due to the situation in the U.S., there were more recently also in Europe considerable unrest among the cattle breeders. Especially the free running of dogs in pastures is considered very critical of cattle breeders, but dogs play for the transmission of the pathogen to cattle hardly matters.