The acute polymyopathy in a seven-year-old German shepherd dog was att
ributed to the muscular hypertonia, tremors and seizures which develop
ed during the acute phase of carbamate poisoning. After two days of ge
neralised muscular rigidity, the dog adopted a characteristic fetal po
sition which could be explained by the imbalance between the injuries
to the extensor and flexor muscles. The polymyopathy resolved graduall
y over the course of a week.