[Occurrence of struma in cattle in the Czech Republic]

In the years 1988 to 1995 among 1355 cattle examined in the frame of iodine deficiency studies in the Czech Republic 404 animals (30%) showed congenital struma. Clinical and postmortal findings are described. A monitoring of iodine content in milk showed lower values in herds with struma prevalence. The insufficient supply of iodine in these animals results from low iodine content of feed or from the goitrogenic influence of nitrate in drinking water or high content of crucifera in feed or other stress factors. An increased iodination of mineral mix in feed is highly recommended.