[Action of herbicide "Atrazine" on thymus and bursa in chickens]

Changes were induced in the central lymphatic organs of chicken which had been given 150 ppm "Atrazin" in their rations over 21 days, beginning with the third day of age. The substance did not produce toxic phenomena. Thymus and bursa fabricii weights went up in parallel with the glycogen levels of those organs, after 15 days of feeding. Normalisation occurred on the 21st day of treatment and was more conspicuous on the thymus than on the bursa.