FURAZOLIDONE TOXICOSIS IN YOUNG BROILER CHICKS - MORPHOMETRIC AND PATHOLOGICAL OBSERVATIONS ON HEART AND TESTES

Broiler chicks 1 d and 3 w of age were given 0, 400, 800, or 1000 mg f urazolidone (Fz)/kg feed for 4 w. Bi-ventricular heart dilatation (as measured by increases in ventricular diameter and thinning of the vent ricular walls) was present in 1-d-old chicks fed 800 mg Fz, whereas in 3-w-old groups these changes occurred at 1000 mg Fz. There was no hea rt hypertrophy. Microscopic changes in the heart were not discernible in and Fz-fed birds. The liver had congestion and cytoplasmic vacuolat ion of hepatocytes. About 37-50% of the male birds in the different Fz -fed groups had testicular degeneration varying from mild to cystic en largement. The degenerated testes had dilatation of seminiferous tubul es; in cystic testes the seminiferous tubules were extremely dilated a nd had flattened epithelium. The interstitial tissue between the dilat ed tubules was compressed and atrophic.