UPV Digital RepositoryUPV-DRUniversity of the Philippines Visayas
 

UPV Theses and Dissertations

Permanent URI for this communityhttps://hdl.handle.net/20.500.14583/10

Browse

Filters

Settings

Has files: YesKeyword: search.filters.keyword.Metamorphosis

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    The effect of different feeding schemes on mudcrab Scylla serrata larvae fed with Artemia salina
    Bachoco, Anabelle M. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1998-04)
    The study on the effect of different feeding schemes of mudcrab Scylla serrata fed with Artemia salina was conducted to identify the zoeal stage of S. serrata where an addition of Artemia to the diet results to higher survival, shorter intermoult duration, higher growth index, and shorter metamorphosis to the megalopa stage. All treatments were fed with Brachionus at a density of 20 ind./ml. Results showed that larvae fed with Artemia from day 0 had consistently high percent survival and this is significantly higher compared to other treatments. This was followed by larvae fed with Artemia at day 3 and at day 6. However, statistical analysis showed that there is no significant difference between the two treatments. Significantly low percent survival was obtained on larvae fed with Artemia at day 9. Results also showed that larvae fed with Artemia at day 0 metamorphosed to megalopa stage after 18 days and obtained the shortest average intermoult duration of 3.6 days and highest growth index of 5 6. This was followed by larvae fed with Artemia at day 3, day 6, and day 9. Artemia has high nutritive value which contributed to high survival, shorter intermoult period, high growth index and shorter metamorphosis period up to the megalopa stage.
  • Thumbnail Image
    Item
    Survival and metamorphosis of the mud crab Scylla tranquebarica larvae fed with Brachionus plicatilis and Artemia nauplii
    Ballescas, Ella Anne M. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2004-03)
    Despite the growing corpus of research on cultural nationalism, the state's role in producing cultural nationalism in a post-colonial and non-western setting and the phenomena from a bottom-up perspective continues to be little explored. This study examines the conditions under which national political leaders pursued policies to protect the cultural heritage of the country's indigenous cultural communities for the aims of political nationalism. From a top- down perspective, the study looks at the context, intent, content, state's implementation and caveats of the Indigenous Peoples Rights Act of 1997. While from the bottom-up perspective, the study looks at how the Bantoanon indigenous community mobilizes and organizes to navigate through state bureaucracy and ‘reappropriate’ the state's nationalism to meet their cultural goals. To examine the phenomena, the study on the textual analysis of existing written primary and secondary sources supplemented with oral interviews of key informants and a review of available literature. It finds that at the national level, political motives partly animated the support of political leaders for indigenous cultural heritage protection policies; that the state used heritage protection policies to pursue its political purposes; and that the support for political leaders for indigenous cultural heritage protection policies was premised on the condition that it did not interfere with the state's interests and diminish the state's rights. While at the Bantoanon indigenous cultural communities level, it finds that despite the caveats embedded in the country's heritage protection policies, the indigenous cultural community could mobilize and assert its rights, thus enabling it to ‘reappropriate’ the state's political institutions to meet its own cultural objectives. This thesis, therefore, argues that the relationship between the two parties under IPRA is mutually beneficial, with both the state and indigenous cultural communities finding some utility in the law.
  • Thumbnail Image
    Item
    Effects of sodium Iodine -enriched brine shrimp (Artemia salina) on the growth, survival and metamorphosis of Rabbitfish (Siganus guttatus) bloch larvae
    Legaspi, Ma. Irene C. (Institute of Aquaculture, College of Fisheries and Ocean Sciences, University of the Philippines Visayas, 2018-06)
    Metamorphosis is considered the most crucial stage in larval fish development that dictates the overall larval fish survival and production output in a hatchery system. This physiological process is modulated by thyroid hormones produced from the thyroid gland the biosynthesis of which is dependent on the supply and availability of the mineral iodine. The present study evaluated the supplementation of iodine to rabbitfish (Siganus guttatus) larvae to determine the influence of this mineral on thyroid hormone levels, metamorphosis, growth performance, stress tolerance, and survival. To efficiently deliver iodine to the larvae, the enrichment protocol was optimized by exposing the Artemia to increasing concentrations of this mineral (0.05 g L-1,0.1 g L-1, 0.2 g L-l, 0.4 g L-1 and 0.8 g L-1). The best iodine enrichment treatment was selected (0.8 g NaI L-1) and used to evaluate the influence of this mineral on larval development, growth, metamorphosis, stress tolerance, and survival. Results suggest that growth of rabbitfish in terms of body weight was higher in the treated group (0.20±0.01g) as compared to the control group (0.14±0.01g). This significant growth response is associated with accelerated period of metamorphosis by 11.2 days and a lower muscle fiber count in the treated group (0.003±0.005 μm2-1). Higher levels of triiodothyronine (T3) and thyroxine (T4) were also observed in the group receiving the iodine-enriched Artemia that coincides with the larvae’s accelerated period to metamorphose. T3 in the treated group (15.31±1.22 ng g-1) is higher compared with the control (8.67±1.5 ng g-1) and T4 in the treated group (459.25±136.9 ng g-1) is also higher compared with the control group (170.86±92.55ng g-1) at 27 days after hatching which coincides with the onset of metamorphosis leading to early metamorphosis of larvae in the treated group. In addition, the present results showed that the larvae in treated group were significantly tolerant to stress, quantified as the cumulative stress index (15.33±2.40 CSI) indicating the positive response of the larvae to the dietary iodine enrichment. In summary, sodium iodide-enriched live food (Artemia) accelerated rabbitfish larvae metamorphosis, improved growth and stress tolerance in rabbitfish larvae. The results of this study can be used as a model iodine enrichment protocol to improve the hatchery output of other high-valued marine fish species in culture.