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Document Type |
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Thesis |
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Document Title |
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Effect of environmental pollutants in Jeddah province coast on metabolism of Ghost crab (Ocypoda saratan) تأثير الملوثات البيئية في سواحل محافظة جدة على أيض السرطان الشبح (أوكيبودا ساراتان) |
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Subject |
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biological sciences department |
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Document Language |
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Arabic |
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Abstract |
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This research studies the effects of environmental pollutants in Jeddah province coast on metabolism of Ghost crab (Ocypoda saratan). The population dynamics and reproductive aspects of the ghost crab, Ocypoda saratan were also studied in Jeddah, Saudi Arabia. Crabs were randomly sampled on monthly basis during low tide periods from January to December 2011 at costal shores of Jeddah province. A total of 82 crabs was obtained, of which 37 (45.1%) were males, 24 non-ovigerous females (29.3%) and 21 (25.6%) ovigerous females, respectively. The present population presents non-normal size frequency distributions, with males reaching greater size than Females were dissected under a stereomicroscope and their ovaries removed, identified, and stored with their respective females. Afterwards, both females and gonads were weighed using an analytical balance (0.0001 g) after drying at 70 °C for 12 h (Yamaguchi, 2001b). The gonadosomatic index was calculated according to the following formula: GSI =GDW⁄FDW× 100 where GDW is gonad dry weight and FDW is female dry weight, respectively. To estimate fecundity, 20 ovigerous females with eggs at stage I were selected for egg counting. Pleopods were removed from females, placed in petri dishes filled with seawater, and eggs detached by the gradually addition of a solution of sodium hypochlorite. Bare pleopods were then discarded by gently stirring in a beaker filled with 200 ml seawater. Three 1.5 ml sub-samples were taken using a pipette, with eggs counted under a dissecting microscope. The average value obtained was then extrapolated for the whole suspension to estimate the number of female's eggs. The overall sex ratio (M:F) (1:0.84) was significantly different from the 1:1 ratio. Ovigerous females were present throughout the year and the embryonic development showed synchrony with the gonadosomatic index, in which females carrying eggs close to hatching were more abundant when the gonadosomatic index reached minimum values in the population. Egg number increases with female size. Juvenile recruitment was also continuous with high proportion of young recruits being recorded in winter, probably due to the high reproductive activity displayed in summer. |
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Supervisor |
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Prof. Hussein Khamis Hussein |
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Thesis Type |
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Doctorate Thesis |
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Publishing Year |
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1434 AH
2013 AD |
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Added Date |
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Saturday, June 15, 2013 |
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Researchers
| مازن عطية السلمي | Al Solami, Mazen Attia | Researcher | Master | |
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