UPV Theses and Dissertations
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Item The effect of different levels of salinity on the spanning of ablated mudcrab Scylla serrataBueno, Jesse L. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1994-04)Four salinity treatments with salinity levels of 15 ppt, 25 ppt, 35 ppt and 45 ppt with six replicates per treatment were utilized to determine its effect on the spawning of sexually mature bilaterally ablated mud crab Scylla serrata. The crabs range in weight from 250 grams to 580 grams and carapace width from 12.5 cm. to 16.5 cm. The results of the study showed significant difference (P<0.05) in the number of days when spawning occurred. The shortest duration when spawning occurred was at 25 ppt salinity with a mean value of 9.5 days. This was followed by 35 ppt and 15 ppt salinities with mean values of 15.69 days and 19.83 days respectively. Highest number of days when spawning occurred was at 45 ppt salinity at 24 days. All crabs died 2-3 days after spawning.Item Determination of the fungal flora in the rearing water, eggs, larvae and post-larvae of Penaeus monodon in a large-scale hatchery systemBaes, Glanee F. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1995-03)The rearing water and homogenized. eggs, larvae, post-larvae of Penaeus monodon were taken front the large-scale hatchery system. These were counted, isolated and identified. Analysis was done by determining the mean, standard deviation and skewness of the data. The result showed that the skewness of the yeast and mold counts in the rearing water were 0.93 and 0.64, respectively 'while that in the homogenized samples were 0.92 and 1.09, respectively. These showed that the data were positively skewed, hence, fungi were greater in the early larval stages than in the later stages. The mean showed that yeast yielded greater counts as compared to the molds. Furthermore, rearing water have also higher fungal count than that of the homogenized prawns. The fungi identified were Aspergillus, Balanium, Bispora, Cladosporium and Phialomysis. In the study, the fungi identified were the normal mycoflora which did not adversely harm the prawn due to favorable hatchery conditions, there being no disease outbreak during the duration of the study.Item A preliminary study on the extraction of alginic acid from three species of brown algae: Sargassum polycystum, Sargassum cristaefolium and Turbinaria sp. in Taklong Is.,GuimarasAdelantar, Geoffrey V. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-04)Three species of brown algae were harvested in Taklong Is., Guimaras. These were Sargassum polycystum, Sargassum cristaefolium, and Turbinaria sp. These brown algae were subjected to physical and chemical treatment to extract and compare the amount of their alginic acid in the form of sodium alginate. Four seaweed collections for extraction were made between August to December, 1995. Values obtained during the first three extractions gave almost similar results. S. polycystum exhibited the highest percentage yield of sodium alginate with a mean of 22.84%. It was followed by S. cristaefolium at 22.21%. Turbinaria sp. gave the lowest yield with a mean of 14.12%. The last extraction somehow showed a decrease in the percentage yield of all three samples. S. polycystum yielded just 20.00%, S. cristaefolium at 19.00% and Turbinaria sp. at just. 10.10%. Several factors may have contributed to the differences in the amount of alginic acid of the three species of brown algae. Among these are the inherent capability of the different species of brown algae to produce alginates, the thickness and sturdiness of the samples, the viscosity of the extracts, and seasonal changes.
