Experimental furazolidone toxicosis in broiler chicks: effect of dosage, duration and age upon clinical signs and some blood parameters.

Groups of broiler chicks of one day and three weeks of age were given feeds containing 0, 400, 800 and 1000 mg furazolidone (Fz)/kg for three weeks. The age of the birds and the dose and duration of Fz treatment significantly (P < or = 0.05) influenced the parameters studied. Clinical signs of Fz toxicosis included ascites, leg weakness and nervous derangement like convulsions and torticollis. The body weight also decreased. Ascites and nervous derangement was not observed in birds fed 400 mg Fz from one day of age. Fz-fed birds developed anaemia and had lower plasma total protein and albumin levels than those fed no Fz. The decrease in body weight was related to reduced feed intake. Decreases found in the haematological parameters and plasma proteins showed no correlation with the chicks' age but were related to the dose and duration of Fz treatment.