ABSTRACTA six‐week‐old female borzoi puppy from a brother‐sister mating developed a generalised illness characterised by anorexia, temporary intention tremor, episodic pyrexia, tachypnoea, conjunctivitis, otitis and neck pain. Haematological abnormalities included an inflammatory leukogram and regenerative anaemia. Blood cultures remained sterile; clinical chemistry values were unremarkable. The puppy had recurrent seizures and was euthanased when 18 weeks old. Post mortem examination revealed a multisystemic inflammatory disease involving thyroids, lymph nodes, spleen, pancreas, bladder and lung, but no lesions to account for the neurological signs. The cause of this generalised disease was not recognised. The histological features are unusual and resemble those described in other dogs of this