ABSTRACT
In this work, ketamine was used to study its effect on the development of spinal cord and testes of chick embryos using 70 fertile Dokky-4 eggs. The embryos were extracted on 10, 14 and 17 days of incubation and examination of the spinal cord and testes was done. The spinal cord showed retardation of its growth with degenerative changes which persisted till the age of 17 days in the form of a decrease in the density of the cells in the four layers of the dorsal horn and in the internuncial region, few widely separated cells in the ventro-medial and ventrolateral motor column and a reduction in the fibers of the white marginal layer. The degenerative changes were marked at the age of ten-day and moderate at the age of 14 and 17 day-old treated embryos in the form of a presence of variable sized cavities throughout the spinal cord. The testes of ten-day-treated male embryos showed thick germinal epithelium and thin tunica albuginea with undeveloped seminiferous tubules. In 14 and 17 days treated embryos, the seminiferous tubules lost their pattern and shape and the stroma became swollen with few interstitial cells. The spermatogonia could not be observed