Effect of Co-60 external irradiation on the testis of house sparrow (Passer domesticus, Linnaeus) after testosterone propionate administration.

External irradiation/House parrow/Testosterone propionate Adult, male house sparrows (Passer domesticus, Linn.) during recrudescence phase were divided into 4 groups. Gpoup i served as control ; group ii received total 2.5 mg of testosterone propionate (T. P.) ; group iii. birds were exposad to 450 R from a Co-60 source; group iv. birds were exposed to 450 R after administering 2.5 mg of T. P. There is no significant change in the body weight ih all the experiments. However, there is marked change in the testis weight in various groups. There is an increase in the testis weight of birds of group ii, but a signi ficant decrease in the testis weight of birds of group iv. The testes show marked histo pathological changes in group iv. The testes show depletion of spermatozoa, pyknotic sper matocytes, exfoliation of spermatids and formation of giant cells.