An Adult Triploid Chicken (<i>Gallus domesticus</i>) with a Left Ovotestis

Abstract

Cytological studies of a fully-grown Rhode Island Red chicken (<i>Gallus domesticus</i>) with ambiguous sexual characteristics revealed a triploid chromosome constitution with two Zs (3A-ZZ). While this bird had the left oviduct and right rudimentary gonad of a normal hen, the left gonad was like an ovotestis with a sharply defined cortex and medulla. In the cortex were embryonic ovigerous cords containing oöcytes in first meiotic prophase; those oöcytes which had reached dictyotene and formed primordial follicles were degenerative. In the medulla were well-developed seminiferous tubules, a few of which contained sperm heads, although in most spermatocytes, meiosis had not proceeded very far. No diploid cells were found in squash preparations of spleen, bone marrow, or gonad; both somatic cells and germ cells were triploid.