| dc.description.abstract | Young German Shepherd dogs (6-12 months) were fed pyrethrum (10, 25, 50 or 100 mg/kg body weight) added to food for 90 days. At 100 mg/kg the pyrethrum was neurotoxic, progressively causing ataxia, clonic convulsions, and tetanic convulsions accompanied by dyspnoea and frothing over the first 3 h of feeding. The dogs lost up to 25% of body weight, became anaemic and developed skin sores between the paws. Histopathological changes were marked fibrosis and haemosiderin deposition in the spleen and liver. The cerebellar neurons showed chromatolysis, especially below the granular zone. No drug-related hormonal or histological changes were seen in the pancreas, ovary, testis, thyroid gland or kidney. No haematological or biochemical changes were noted except for a transient rise in serum transaminases. Changes were less with 50 mg pyrethrum/kg body weight and absent at 25 mg pyrethrum/kg body weight. This, at a food consumption of 7% of body weight per day amounts to a food contamination of more than 30 mg/kg. This level of contamination is improbable from commercial use of pyrethrum. It is concluded that pyrethrum use in the home is not a threat to pets or man. | en_US |
