UPV Theses and Dissertations
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Item Comparative development of larval performance of catfish hybrids (Clarias macrocephalus Gunther x Clarias gariepinus Burchell)Cabanos, Cerrone Salamat (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2003-03)Our native catfish, Clarias macrocephalus, is one of the most well-accepted fish in the country. With its soft and savory flesh, this species has high demand in local markets. However, due to its relatively slow growth and poor breeding activity, our native catfish has become rarely used nowadays in aquaculture. This led to the introduction of exotic and faster growing species like the African catfish, Clarias gariepinus, and Thai catfish, Clarias batrachus, which in turn, resulted to the near extinction of the native species. There is therefore a perceived need to undertake a breeding program involving this native catfish and other exotic species. One potential solution to increase our production rate of the native catfish is to hybridize it with the African catfish. Interspecific hybridization has been a popular breeding program utilized by researchers attempting to produce fish expressing hybrid vigor (positive heterosis) or for combining valuable traits from more than one species. This study is on the characterization of the early developmental stages of fertilized eggs and the comparison of larval performance (in terms of percent fertilization, hatching and larval survival) resulting from the artificial cross of Clarias macrocephalus (native catfish) and Clarias gariepinus (African catfish) and its parental species. In comparing the rates of egg development among crosses (all macrolecithal and discoidal cleavage), it was determined that fertilized eggs of the standard hybrid cross (C. gariepinus male x C. macrocephalus female) have a relatively faster rate of development than those from the reciprocal cross (C. macrocephalus male x C. gariepinus female). Results on determination of larval performance showed that there is no significant difference in percent fertilization and percent survival after 7 days between hybrid and parental crosses. However, in terms of percent hatching, the reciprocal hybrid cross (C macrocephalus male x C. gariepinus female), together with the C. gariepinus x C. gariepinus parental cross had a significantly higher percent hatching (P < 0.01) compared to the standard cross (C. gariepinus male x C. macrocephalus female).Item Microbiological assessment and detection of potentially pathogenic bacteria on three areas along the Iloilo RiverCaballo, John Carlo P. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2011-04)The Iloilo River, which traverses the whole length of Iloilo City, serves as a water source for different human activities hence, subjecting it to a variety of pollutants. Microbial and physico-chemical parameters of the three areas along the Iloilo River (Carpenter’s Bridge, IBRD Bridge, and Dungon Creek) were assessed to in order to provide a quantifiable evaluation of the river’s water quality. The presence of Salmonella spp., Eschericia coli, Streptococcus spp. and Vibrio spp., was also determined. HPC counts indicate very-high to extremely-high levels of bacterial loading (5.31 x 105-l .60 x 106 CFU/lOOmL) among the three sampling areas. Total coliform levels indicated contamination of the river from outside sources, potentially from domestic sewage discharges and run-offs from nearby establishments. The FC: FS ratio suggests contamination mostly came from mixed origins, with the noted exception of Carpenter’s Bridge, which is dominated by human fecal contamination. Minimal variations in physico-chemical parameters were observed for all areas. Significant correlations were found among salinity (p=0.002) and temperature (p=0.042) with TC; between FS with dissolved oxygen (p=0.00), and between FC and temperature (p=0.005). Contamination of the river by organic and fecal matter from animal and human sources provided a suitable habitat for pathogenic bacteria. A considerable quantity of potentially pathogenic bacteria such as; E.coli, Salmonella spp., Streptococcus spp. and Vibrio spp., were isolated from each sampling area. Exposure to these pathogens in drinking and recreational waters poses health risks to local inhabitants and to any individual who would consume water from the riverItem Abundance, composition and vertical distribution of calanoid copepods in Central Sulu seaBurgos, Lora A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2018-06)Calanoid copepods are dominant component of the copepod community, which in turn highlights their influence on the overall zooplankton assemblage of the water column. Studying their abundance and distribution, is important on understanding their role in the dynamics of commercially important organism like the fish. Calanoid samples in study, were part of the zooplankton samples taken during the Joint PhilEx oceanographic cruise on board RAZ Melville in December 2007 in the Central Sulu Sea from MOCNESS station 29. Calanoid abundance, composition and distribution were investigated. Fifteen (15) calanoid families were identified all throughout the water column (0 - 400 m). The calanoid assemblage was dominated by 27 % Eucalanidae, 12 % Rhincalanidae, Scolecitrichidae with 7 % and other families contributing to roughly 19 % of the total. The water column was divided into 2 distinct depth cluster based on species distributions; (1) layers above thermocline (0 - 150m) and (2) deeper layers (200 - 400m). Furthermore, upper layers were characterized by distinctive calanoid family assemblage which includes; Calanidae, Euchaetidae, Eucalanidae, Candaciidae, Rhincalanidae, and Temoridae. While deeper layers, calanoid families includes; Metridinidae, Scolecitrichidae, Rhincalanidae, and Euchaetidae. ANOSIM results showed significant differences between these depth clusters, with global R = 0.81 and p = 0.01. These appear to be highly related to the thermocline in both stations, where typically higher upper-layer primary productivity can support dense communities of zooplankton.Item Mangrove community structure survey in Barangay Guisi and Linayasan, Altavas, AklanBullo, Gliford G. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2004-04)The mangrove forest is a complex and unique community of medium to large tress, shrubs, vines and palms, oddly thriving with luxuriant growth in the least inviting habitats which have the barest and limited conditions for the growth and survival of higher plant life. This study aims to assess the community structure of mangroves in Barangay Guisi and Linayasan, Altavas, Aklan using accepted ecological indicators. The sampling site, Altavas, Aklan is located at the upper median of Panay Island. There was a total of 15 true mangrove species belonging to the 9 families in the area. The nine families are Family Myrsinaceae represented by Aegiceras corniculatum, Family Avicenniaceae represented by Avicennia alba, Avicennia marina, Avicennia officinalis and Avicennia rumphiana; Family Rhizophorceae represented by Rhizophora apiculata, Rhizophora mucronata, Bruguiera gymnorrhiza and Bruguiera parviflora; Family Bombacaceae represented by Camptostemon phihppensis; Family Rubiaceae represented by Scyphiphora hydrophylaceae; Family Meliaceae represented by Xylocarpus granatum and Family Palmae represented by Nypa fruticans. Avicennia rumphiana has the highest mean basal area of 23.21 (m2/ha), while Xylocarpus granatum had the lowest mean basal area of 0.01 (m2/ha). Avicennia rumphiana has the highest relative density of 57, while Xylocarpus granatum has the lowest relative density with a value of 1. Avicennia rumphiana and Avicennia officinalis had the highest relative frequency of 19.8667 Aegiceras corniculatum, Excoecaria agallocha, Scyphtphora hydrophylaceae and Xylocarpus grunatum on the other hand had the lowest relative frequency of 0.4. Avicennia rumphiana is the dominant species with a relative dominance value of 23.66, and Xylocarpus granatum is the least dominant species with relative dominance value of 0.01. Avicennia rumphiana is the most important species in the area with an importance value of 127.1816, and the least important species, as observed, is Xylocarpus granatum with an importance value of 1.685863. The index of diversity is 0.918655 for the entire area.Item A preliminary study on the freezing tolerance of milkfish (Chanos chanos, Forskal) embryosBuendia, Jeremiah C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1994-03)Milkfish embryos of blastula and C-shaped stages were tested for cryoprotectant toxicity using DMSO and glycerol at 10%, 12% and 15% concentrations. Survival and hatching as well as the effects of freezing were observed. Glycerol was more toxic than DMSO. Freezing at 4°C resulted in the decrease of hatching, and ice crystal formation killed the embryos during the process of freezing to -80°C. C-shaped embryos had a higher survival and hatching than the blastula stage embryos in the toxicity and cold shock tests.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 Survival and growth of juvenile sea cucumber Holothuria scabra Jaeger (1833) in shrimp pond sedimentBriones, Jill D. (2012-03)Many high valued sea cucumbers e.g. Holothuria scabra are detritivores and thrive on organic matter and thus are potential bioremediating agents in eutrophic systems e.g. aquaculture ponds. Sea cucumbers cultured in shrimp ponds would act as natural bioremediators and lessen the organic matter content of the sediments hence make the pond environment more favorable for shrimp culture. This study looks at the feasibility of growing sea cucumbers in pond sediments for their bioremediating role and for their economic value. In this study, growth and survival of hatchery-produced H.scabra juveniles in Bare substrate (Treatment 1), Sand from natural habitat (Treatment 2) and Shrimp Pond sediment (Treatment 3) were compared after 5 weeks of culture. This study demonstrates that it is feasible to grow H. scabra juveniles in shrimp pond sediments without compromising their survival (p > 0.05). Results showed that those reared in Pond sediment grew best and significantly better compared to the other treatments (ANOVA, p<0.05). Juveniles grown in Pond sediment increased from mean weight of 3g to 14g while in the other treatments they just grew from mean of 2.7g to 8.7g. The consistently higher organic matter in Pond sediment could have contributed to better growth of sea cucumbers relative to other treatments. The bioremediating role of sea cucumbers was indicated by significant reduction in organic matter content in pond sediment by Week 5.Item Mangrove community structure survey in Pedada Bay, Ajuy, IloiloBravo, Mark G. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2004-04)Mangroves are uniquely tropical, globally occurring and one of the most pervasive coastline ecosystems. They are one of the highly productive and one of the most diverse wetlands on earth. The objective of this study is to assess the community structure of mangroves in Pedada Bay, Ajuy, Iloilo, in particular the species composition and diversity in relation to the physical and chemical factors. Pedada Bay is located in the northern part of Panay Island. The transect line plot method was used to survey the community structure of the mangroves. The floristic composition of Pedada Bay was composed of a total of 18 true mangrove species belonging to 11 families. The true mangroves were Family Avicenniaceae represented by Avicennia marina and A. rumphiana, Family Bombacaceae represented by Camptostemon philippinensis, Family Combretaceae represented by Lumnitzera racemosa, Family Euphorbiaceae represented by Exoecaria agallocha, Family Meliaceae composed of Xylocarpus granatum and X. moluccensis, Family Myrsinaceae composed of Aegiceras corniculatum and A. floridum, Family Myrtaceae represented by Osbornia octodonta, Family Palmae represented by Nypa fruticans, Family Rhizophoraceae composed of Bruguiera cylindrica, Ceriops decandra, Rhizophora apiculata, R. mucronata, and R. stylosa, Family Rubiaceae, composed of Scyphiphora hydrophyllacea, and Family Sonneratiaceae, composed of Sonneratia alba. Average basal area for the entire Pedada Bay ranges from 300.564 m2/ha for Sonneratia alba to 0.008 m2/ha for Rhizophora mucronata. Average stems per hectare ranges from 1,988 for Avicennia marina to 5 stems per hectare for Aegiceras corniculatum. Of the three barangays of Pedada Bay, Barangay Pedada had the highest basal area while Barangay Luca had the lowest basal area. Sonneratia alba was the most dominant species in the bay. Avicennia marina was the densest, the most frequently occurring, and the most important species in Pedada Bay. The entire area had a high diversity index of 0.718. A distinct zonation pattern was observed in the area. Seedling density ranges from 1,421 seedlings for Sonneratia alba to 1 seedling for Scyphiphora hydrophyllacea. Sapling density ranges from 166 for Avicennia marina to 1 for Scyphiphora hydrophyllacea.Item Filtration rate of the marine clam, Kaltelysia sp. at different light intensities and fed with microalgae Isochrysis galbana and Chaetoceros calcitransBravo, Agnes Therese A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2005-04)Filtration rate of the marine clam, Katelysia with body lengths ranging from 5-6 cm and body weight from 45-65 g were determined by using the indirect method of suspension depletion and monitored by direct algal cell count. The effects of light intensity and algal species on the feeding behavior of the clam were determined. The first treatment involves total darkness where the basins containing the clams were covered with black plastic bag. In the second treatment, the basins with the clams were placed under ordinary light condition (12h light; 12h dark) and in the third treatment, the basins with the clams were positioned under a 20-watt bulb with continuous illumination (24h light). Results showed significant differences in the filtration rates of clams in different light intensities. It showed higher filtration rate in the total darkness treatment (F=0.132555907) followed by the 12h light: 12h dark treatment and lowest at the treatment provided with 24 h illumination. Apparently, illumination affected valve opening and siphon extension of the clam which also affected the filtration rate of Katelysia. Under total darkness treatment, the clams opened their valves and extended their siphons. Hence, there was highest ingestion of algae or filtration in total darkness which showed to be the optimum condition to stimulate or promote feeding. In the algal species preference experiment, the food used were either Isochrysis galbana, Chaetoceros calcitrans , or a mixture of both. Results showed that I. galbana had the highest number of cells ingested by the clams and removed from suspension. This is considered to be the preferred algal species (F=0.119713) followed by a mixture of both, and lowest on the treatment where C. calcitrans was used as food. The preference of the clam on Isochrysis galbana over Chaetoceros calcitrans could be its smaller size based on dry weight.Item Identification of intertidal fungi from mangroves in Iloilo RiverBonifacio, Jo F. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2002-04)This study aims to describe, identify and classify intertidal fungi through direct examination of the collected mangrove wood samples in Iloilo River, Iloilo City, Philippines. This will provide additional information about the occurrence of fungi in estuarine environments. One hundred samples of decayed but attached roots and stems of unidentified mangroves were collected in each of the intertidal zone of the three study sites (Study Site I: Sooc, Oton, Iloilo; Study Site II: Dulonan, Arevalo, Iloilo City; Study Site III: Diversion River, near Marina Restaurant) in Iloilo River. In Study Site 1, The total number of species collected was 11, 4 of which belong to Phylum Ascomycota, 2 belong to Phylum Deuteromycota and 5 belong to Phylum Basidiomycota. In Study Site II, there were 10, 6 belong to Phylum Ascomycota, 3 to Phylum Deuteromycota and 1 to Phylum Basidiomycota and in Study Site III, total number of species was 14, 7 belong to Phylum Ascomycota, 4 to Phylum Deuteromycota and 3 to Phylum Basidiomycota. The total number of species of fungi collected in the three study sites were 20 (8 ascomycetes, 7 basidiomycetes, and 5 deuteromycetes). The frequently occurring fungi (10-29 % fiequency of occurrence) are Eutypa sp. (15.3%), followed by Periconia prolifica (13 %) and Verruculina enalia (10.3%). The remaining 17 species were collected infrequently (<10 % fiequency of occurrence). The ascomycetes were the most dominant group of fungi collected in this study.