International Journal of Marine Science, 2016, Vol.6, No.18, 1-14
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schizont nucleus began to separate from each other and migrate to the periphery and the host cell, at this time the
host cell is totally occupied with the schizont (21.6 X 16 µm). sporozoites with fusiform shape (4.3 X 1.8 µm)
released and wandered free in the cytoplasm of the host cell. The rest of sporozoites were still attached to the
residual body.
The schizont diameter in this stage was (13.4 X 12.8 µm). The total number of sporozoites in each schizont was
more or less 64.
Figure 9-16: 9. Photomicrograph of a transverse section in intestinal mucosa of
Ciona intestinalis
showing a developing schizont
inside a blood cell. Note: arrows indicate the lobules of the nucleus. 10. Photomicrograph of a transverse section in intestinal mucosa
of
Ciona intestinalis
showing a fully formed schizont. Note: appearance of differentiated merozoites inside the schizont leaving
residual bodies and healthy epithelial cells surround the infected cell underneath. 11. Photomicrograph of a transverse section in
intestinal mucosa of
Styela plicata
showing a multinucleated schizont. Note: destruction of host cell nucleus and deterioration of the
leucocyte. 12. Photomicrograph of a transverse section in intestinal mucosa of
Ciona intestinalis
showing an oocyst. Note: thickness
of its wall especially at its both poles. 13. Photomicrograph of a transverse section in intestinal mucosa of
Styela plicata
showing a
sporocyst with four sporouoites. Note: the residual body at one pole. 14. Photomicrograph of a transverse section in intestinal mucosa
of
Ciona intestinalis
showing a sporulated oocyst containing two sporocysts, each contain four sporouoites. Note: thin of its wall. 15.
Photomicrograph of a transverse section in intestinal mucosa of
Ciona intestinalis
showing a dividing oocyst into two sporocysts.
Note: thin wall. 16. SEM of a transverse section in intestinal mucosa of
Styela plicata
showing a schizont. Note: the schizont is
completely embedded in the intestinal mucosa
.
Second generation schizont
The sporozoites of the first generation schizont now became free of the host infected intestinal epithelia and
entered other cells to form schizonts of second generation (Fig. 22). Each with about 43 nuclei (12.3 X 8.5 µm).
Schizonts enlaged gradually in diameter (15.2 X 10.3 µm) and had similar morphology and characteristics of the
first generation schizont.
