NEOSPORA-CANINUM INFECTION IN THE DOG - TYPICAL AND ATYPICAL CASES

Nine cases of Neospora caninum infection in dogs are reported. Five ca ses are examples of the typical protozoal polyradiculoneuritis-myositi s syndrome in young puppies. In these dogs, the condition was manifest ed clinically as a progressive paraparesis, associated with hindlimb e xtensor rigidity. The other four cases are examples of atypical clinic al presentations of N. caninum infection. They were due to neuromyopat hy in two and encephalomyelitis in one older puppy, and to encephaliti s in an adult dog. In the puppies with neuromyopathy the condition man ifested clinically as lameness and hyperesthesia; in the puppy with en cephalomyelitis, as multifocal central nervous system disease; in the adult dog as abnormal behaviour and partial, central blindness. Diagno sis was confirmed by demonstration of serum antibodies to N. caninum, but not to Toxoplasma gondii, demonstration of N. caninum organisms by immunohistochemistry (in muscle sections in cases with polyradiculone uritis-myositis, and in CNS tissue in cases with encephalomyelitis), a nd by response to treatment with clindamycin in the puppies with neuro myopathy.