Effects of estrogen (17 beta-estradiol) and p-nonylphenol on the development of immune organs in male Japanese quail.

The aim of this study was to determine the effects of estrogen and endocrine disrupters on the immune organs of Japanese quail. We used p-nonylphenol (NP) as a model endocrine disrupter. Birds were injected with 17 beta-estradiol (E2) in doses of 1, 0.1 and 0.01 ng/g body weight and NP in doses of 1000, 100 and 10 ng/g body weight from 4 to 7 weeks of age. The data indicate injection of E2 during the growth phase resulted in cyst formation, increased connective tissue, disappearance of lymphoid cells and disappearance of plicae in the bursa, disappearance of lymphocytes in the thymus and a greater population of trabecular arteries and veins in the spleen. Injection of NP tended to induce many empty vacuoles and increased connective tissue in the bursa of Fabricius but did not affect the structures of the spleen and thymus. We also studied whether apoptosis is involved in the histological changes of the bursa and found that apoptosis did not play an important role in the changes of the bursa. These results suggest that E2 and NP may affect the immune organs and the effect on the lymphoid tissue in immune organs is higher with E2 treatment than with NP.