Plasma, white muscle, red muscle, liver and kidney tissues, following the oral administration of the antibiotic tetracycline (TC), oxytetracycline (OTC) alone or with citric acid, were determined in broiler chickens.

The fluorometric method was used for the determination of the OTC and TC residues in the tissues and plasma. The emission maxima of OTC and TC were at 500 nm and the exitation maxima were at 400 nm. The levels of OTC and TC in all the tissues were fo und to be between 0:041 and 2.86 ppm, 0.003 and 0.116 ppm respectively.