An investigation of the mature gametes of Nematospiroides dubius and a review of the parasitic nematode reproductive system

Both electron and light microscopic techniques were used in this study of the mature male and female gametes of Nematospiroides dubius. Several points which warrant discussion are: change in the morphology, location and appearance of the nucleus, vesicular structures, and the presence of ribosomes and mitochondria after the sperm penetrates the egg. The sperm was found to be composed of three distinct cytoplasmic zones. One contains nuclear material, the central portion contains cellular organelles and the other end is devoid of organelles and appears pseudo-podial in nature. The egg cytoplasm was found to contain numerous yolk granules, mitochondria, vesicular elements, ribosomes and endoplasmic reticulum. In a fertilized egg the sperm pronucleus has undergone great chromatin decondensation and a distinct investing coat is now found around the periphery of the zygote.Biology and Biochemistry, Department o