ABSTRACT
2, 4-dichlorophenoxy acetic acid [2, 4-D] is one of the active synthetic auxins that are widely used to control plant growth. The toxic effect of this plant growth regulator on the development of the testes of rats was investigated in this study on the histological basis. Fifty adult mated female albino rats were used in this study. Twenty animals served as controls and thirty received a daily oral dose of 15 mg/kg of 2, 4-D starting from the sixth day of pregnancy till four weeks after delivery. Specimens were taken from the offsprings of animals at one day, one week, two weeks and four weeks postnatal and examined using light and electron microscopy. Abundant interstitial connective tissue was observed in the testes of one day rats. With progress of development, there was loss of organization of the lining epithelium of the seminiferous tubules with gradual appearance of signs of degeneration and desquamation of the spermatogenic cells to the lumen of the seminiferous tubules. The effect of 2, 4-D on mammalian reproduction could be through estrogen hormone agonistic action which impaired the pituitary testicular axis by inhibiting the neonatal gonadotrophin secretion. The deleterious effect of this synthetic growth promoting hormone on the testes of the new generation must be kept in consideration during its use as plant growth promoting hormone and care must be taken about the food supply exposed to this synthetic hormone