Undergraduate Theses
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Item Fecundity and egg quality in two species of siganids (Siganus canaliculatus and Siganus fuscescens) from Lanuza Bay, Surigao del Sur, PhilippinesAnore, Gaguis Anito II T. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)Siganus canaliculatus and Siganus fuscescens are two of the important yet highly exploited siganid aquatic resources in the Philippines. Only few studies for both species, especially for S. fuscescens, are available in the Philippine setting regarding its fecundity and egg quality. This study was conducted to provide information on the fecundity and egg quality of S. canaliculatus and S. fuscescens from Lanuza Bay, Surigao del Sur, Philippines. Fecundity was determined through gravimetric method in individual gonads. Fecundity range was determined to be 54,856 — 279,957 individual oocytes for S. canaliculatus and 7,397 — 563,722 for S. fuscescens. Fecundities of both species exhibited a weak to strong positive correlation to size, with higher correlation coefficient to standard length for S. canaliculatus and body weight for S. fuscescens. On the other hand, egg quality was determined through mean oocyte diameter, with diameters ranging from 176 — 426 ųm for S. canaliculatus and 171 — 500 pm for S. fuscescens. Mean oocyte diameters of both species exhibited weak positive correlation to size, but with a higher correlation coefficient on standard length. Regulating the capture of smaller-sized fishes and allowing them to grow would promote the increase in fecundity and egg quality of the species.Item Community structure of a ten-year old naturally, regenerating mangrove stand in Baguingin, Tigbauan, IloiloAnimas, Ruphil May J. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1999-04)The structure of the mangrove community in Baguingin, Tigbauan was studied using the transect line plot method with seven plots established. Community structure is described in terms of the following parameters: basal area, stems per hectare, relative density, relative frequency, relative dominance, and importance value of the species and the Shannon Index of Diversity. Variations in these parameters are correlated with certain physico-chemical factors-- air and water temperature, soil pH, water salinity, land elevation- and the degree of human influence. Three true mangrove species were found in the area: Excoecaria agallocha, Avicennia marina, and Avicennia alba. A. marina was found to have the highest relative density of 70.8%. relative dominance of 52.35% and importance value of 169.82. A. marina and A. alba have equal relative frequency of 46.67%. Seedlings and saplings of A. marinadominate the area, indicating that the community is a young and regenerating stand. Basal area significantly increased from sea to land ( 53.68 cm2 to 431.66 cm2) and from creek to land ( 8.83 cm2 to 366.54 cm2). Shannon Index of Diversity gave a result of 0. The very low diversity index means that there is uneven distribution of individual trees among the species, and only a few kinds of species were present and are centered around only two genera, Avicennia species and Excoecaria agallocha.Item Growth of the telescope snail, telescopium telescopium (Linne) in brackishwater pondsApistar, Jobert H. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines, 1998-04)Samples of T. telescopium were collected every month, from April to October 1997 for 6 months, in brackishwater ponds. Allometric relationships were defined by comparing shell length with shell width, as well as various body weight proportions including total weight with shell, total volume with shell, visceral weight and visceral volume. A total of 5 cohorts with growth rates ranging from 0.45 - 0.67 mm-day- were observed using the Bhattacharya analysis. A high mean growth rate of 0.56 mm-day- (sd = 0.07, n= 5) was estimated by joining the modes of the cohorts between successive sampling months. Low inverse correlations were observed between mean shell length and various environmental parameters (i.e. salinity, air temperature, water temperature and organic matter content) possibly explained by the species' environmental adaptations. On the other hand significant correlation was observed between mean shell length and density, indicating the possible role of overcrowding in these habitats.Item A comparison on the effect of light on melanophore differentiation in the larval stage of frog, Hyla sp.Araneta, Merrie Celine E. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-03)Three set-ups were exposed to different experimental conditions namely: set-up A. under prolonged light: set-up B. under prolonged darkness: set-up C. under normal condition. Observation was done under the dissecting microscope from the first appearance of melanophores until the migration was stabilized. The pattern of differentiation was observed to be the same in all set-ups. only the distribution and the color intensity differred. B was the darkest and C was the lightest. It only showed that light could not, alter the pattern of melanophore differentiation, only the distribution.Item Larval rearing of Scylla serrata Forskal: The effect of Artemia salima and Brachionus plicatilis as food on the growth and survival of zoeaApote, Ma. Noemi G. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1996-11)A study was conducted to find out tile effects of Artemia, Brachionus and a combination of Anemia and Brachionus as food on the survival of mudcrab Scylla serrata Forskal zoea and the ability of the zoea to metamorphose to megalopa stage. The study composed of three experiments. Each experiment lasted for 21 days. Results showed highest mean percent survival (66.7±2.03) on zoea fed with a combination of Anemia and Brachionus at a feeding density of 5 individuals/ml each. When the density of Brachionus was increased from 5 individuals/ml to 12 individuals/ml in the combination diet, there was an increase in the survival of the zoea to 68.9±2.41. Highest metamorphosis from zoea to megalopa was also obtained on those fed with a combination of Anemia and Brachionus. This combination diet also gave the shortest number of days for the zoea to metamorphose to the next stage which also resulted to the least number of days for megalopa production to start. The study also revealed that larvae ted with a combination of Anemia and Brachionus reared at 30 ppt salinity got high survival on the first three days of culture, however starting on the 4th day up to the 15th day of culture, those reared at 28 ppt obtained higher survival although not statistically different from the other salinities tested.Item Effect of varying levels of cotton (Gossypium sp.) seed meal on the spermatogenesis of mice (Mus musculus)Abonador, Luena A. (Division of Social Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1992-04)Cottonseeds procured from Western Colton Corporation, Oton, Iloilo were dehulled, cleaned by hand, and ground using a mortar and pestle. Ground cottonseed meal (CSM) was incorporated in varying amounts into the basal diet so that diets contained varying levels (0,10,20,30 g) of CSM per 100 g formulated diet. These were then pelletized at the Nutrition and Feed Division, Aquaculture Department (AQD), Southeast Asian Fisheries Development Center (SEAFDEC), Tigbauan, Iloilo. A total of thirty-two 20-day-old male mice (16 white and 16 black) were randomly distributed to four dietary treatments, each with four replicates. After a 5-day acclimatization period, during which the mice were fed with the basal diet (0% CSM), the four experimental diets were given to the randomly selected experimental animals for another 35 days. The mice were subsequently sacrificed, and histological examination of the testes was conducted. Differential count of sperms was done to evaluate the effects of varying levels of CSM on the spermatogenesis of mice. The data obtained were analyzed statistically using analysis of variance followed by Duncan’s Multiple Range Test. There was no significant difference in the sperm counts of the two strains of mice. However, significant differences (P<0.01) were noted in sperm counts of mice at various levels of CSM in the diet. Likewise, significant differences (P<0.01) were observed between 0% and 20 or 30%; 10% and 20 or 30%; 20% and 30% CSM in the diet. No significant difference was noted between sperm counts of mice fed with 0% and 10% CSM levels. Slight degeneration of the seminiferous tubules and predominance of immature stages (spermatogonia) were observed in the testes of mice fed with diet containing 30% CSM.Item A survey of the catch composition of fyke nets in the Iloilo riverAndrada, Kristina Abelaine D. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-04)A survey of the catch composition of fyke nets in the Iloilo River Estuary during the months of August 1999 and February 2000 show that catches are dominated by Metapenaens crisis and (ilossygobius sp. The 18 species caught are : 9 fish species, 5 shrimp species, and 4 crab species. The index of similarity 0.3 between the monthly samples is low which means that there is minimal degree of similarity between the species composition of the catches. There is no significant difference between the total catch volumes per day for the months of August 1999 and February 2000 which means that the seasons do not affect the volume of the catch.