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Issue Description
Neosporosis is an infectious disease primarily of dogs and cattle. Due to the similarity of Neospora caninum to Toxoplasma gondii, neosporosis for many years was misdiagnosed as toxoplasmosis. Neosporosis was first described in dogs in Norway in the mid-1980's as causing neuromuscular degeneration leading to hind limb paralysis. Neosporosis now appears to a major cause of abortion in dairy cattle worldwide. The disease has been found in many countries around the world, but appears to be an important cause of reproductive failure in cattle in the U.S., Netherlands and New Zealand.

Symptoms and Diagnosis
Neospora caninum infects domestic dogs worldwide with varying prevalence. Studies testing dogs for antibodies to the parasite suggest that more than 30% of dogs are infected in some areas, with the highest numbers in South American countries and in rural dogs, especially those living on cattle farms.

Most infected dogs have no symptoms. When symptoms occur, neosporosis is most severe in newborn puppies, infected during gestation when the parasites move from the bitch's tissues to the fetus. Puppies suffer paralysis, particularly of the hind legs, and often do not survive. Adult dogs may suffer from an illness similar to toxoplasmosis in cats, or they may develop dermatitis.

Information on effective therapy for this disease is limited. Clindamycin, sulfadiazine, and pyrimethamine alone or in combination have been administered to treat canine neosporosis. However, clinical improvement is not likely in the presence of muscle contracture or rapidly advancing paralysis. To reduce the chance of illness, all dogs in an affected litter should be treated as soon as the diagnosis is made in one littermate. Older (>16 weeks) puppies and adult dogs respond better to treatment. There is no known therapy to prevent a bitch from transmitting infection to her pups.

In dogs, N. caninum can be transmitted repeatedly through successive litters and litters of their progeny. This should be considered when planning the breeding of Neospora-infected bitches. Dogs should not be fed uncooked meat, especially beef. There is no vaccine to combat neosporosis. No drugs are known to prevent transplacental transmission.

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