UPV Theses and Dissertations
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Item Analysis of the lipid content of micro algae species used in Philippine aquaculture for their potential in biodiesel productionFerriols, Victor Marco Emmanuel N. (Institute of Aquaculture, College of Fisheries and Ocean Sciences, University of the Philippines Visayas, 2008-03)This study looked into the proximate lipid content of four micro algal species (Chaetoceros calcitrans, Tetraselmis tetrahele, Nannochloropsis sp., and Chlorella sp) and one macrophyte (Chaetomorpha sp.) commonly used in Philippine aquaculture. Prior to the proximate analysis using the method described by Bligh and Dyer (1959), the four micro algal species were cultured for five days in 1 L vessels fertilized with TMRL enrichment media. Proximate gravimetric analysis showed that the average lipid content of Tetraselmis tetrahele at 24.11% was significantly higher (p < 0.01) when compared to all the algal species tested. Comparing the mean lipid content of all micro algal species against that of the macrophyte also revealed a significantly higher (p < 0.01) lipid content at 17.40%. Growth rates for all the micro algal species over the culture period was also measured, with the highest growth rate exhibited by T. tetrahele at 1.15 divisions per day. Projected estimates for micro algal production yields of oil from a 1-hectare pond at 0.5 m depth were also calculated from the lipid analysis data, a showing that the highest yield of oil (7.29 tons) can be attained by culturing T. tetrahele. This number was higher than estimated reports for oil production from an area of 1 hectare dedicated to either jatropha (1.7 tons) or coconuts (5.0 tons). This makes the culture of micro algal species a potential option for producing feedstock for biodiesel production.Item Growth performance, feed utilization and survival against stress test of juvenile Nile tilapia Oreochromis niloticus fed with lactic acid bacteria (lab) Pediococcus acidilacticiSO, April Dawn P. (University of the Philippines Visayas, 2016-06)ABSTRACT The present study evaluated the growth performance, feed utilization and survival against stress test of Nile tilapia, Oreochromis niloticus fingerlings (mean initial average body weight 0.39g ± 0.01) fed with commercial probiotics. The experimental design was randomized, with four treatments and four replicates: Treatment 1 (control) with 0g kg-1 probiotics inclusion, Treatment 2 with lg kg1 probiotics inclusion, Treatment 3 with 2g kg'1 probiotics inclusion and Treatment 4 with 4g kg'1 probiotics inclusion. Three hundred and twenty fingerlings were distributed in 16 50L containers and fed for 40 days. Differences in the mean values of total weight were found at the end of the experiment. After 40 days of feeding trial, percent weight gain (%WG), specific growth rate (SGR) and and feed conversion ratio (FCR) was significantly high (P < 0.05) in treatments with probiotics compared to probiotic-free treatments; no differences on survival rate (SR) was observed among dietary treatments. The best growth performance and feed conversion was observed in fishes fed with 4g kg'1 probiotics inclusion. Challenge was done immediately after the period of application. The stress challenge test was done to the experimental animals by exposure to oxygen deficient water or asphyxia. No significant difference (P < 0.05) on SR was observed after 3 hours exposure to asphyxia. It could be concluded that probiotics can improve growth performance and feed utilization. However, further studies are recommended to assess the effects of probiotics to fish when exposed to asphyxia.