Article

The Structure of the Ovarian Ball and Oogenesis in Moniliformis dubius (Acanthocephala)

Journal of morphology (Impact Factor: 1.74). 04/1976;

ABSTRACT

Seven to nine days after infection of the definitive host (rat) by cystacanths, the genital primordium of the female acanthocephalan is transformed from a fragmented mass of cells into discrete ovarian balls. This is accomplished by envelopment of free germinal cells by somatic tissue which originates from the ligament sac primordium. Germinal cell nuclei then undergo repeated mitoses until about 21 days of development, with concurrent formation of oogonial syncytia which occupy the interior of the ovarian balls. Oocytes derived from these oogonia move to the periphery of the germinal syncytia for differentiation, growth, fertilization, shell formation and release from the ovarian ball. After oogonial proliferation ceases, continued growth of the ovarian ball apparently results from increase in size of already present cells.

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