Fig. 5.

Ovary of Alligator mississippiensis at five months after hatching in parasaggital view stained with PAS/AB showing nests of germ cells in various stages of oocyte maturation and location. A and B: Cortical germ cells with mitotic chromosomes (Gch) and uni-nucleated (S1) and multinucleated (MNO) Stage-1 oocytes with diplotene chromatin are observed in germ cell nests. Stage-2 (S2) and -3 (S3) oocytes are observed in regions with direct connection to an adjacent medulla. S2 oocytes display enlarged ooplasms, PAS-positive Balbiani bodies (B), and a thin, irregular PAS-positive basement membrane (black triangles), but lack a distinct full complement of encircling follicular cells. S3 oocytes display PAS-positive Balbiani bodies (B). In contrast to S2 oocytes, S3 oocytes have a complete ring of follicular cells (F) and a distinct, encompassing PAS-positive basement membrane (BM). S3 oocytes may be contained in a multioocytic follicle (MOF) with a lack of follicular cells and basement membrane demarcation between germ cells (diamond). Coelom = (*). C: Putative germ cells (pGC) are observed in tubules within the medullary rest of the alligator ovary. A PAS-positive basement membrane (BM) associated with squamous, myoid-like cells (Sq) encompasses an aggregate of putative germ cells with large cytoplasms and displaying nuclei with fibrous chromatin. Interstitial tissues display cells with Leydig cell morphology (pLe). Scale bars = 50 um.