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UPV Theses and Dissertations

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    Zooplankton composition, abundance and diversity in selected Municipalities of Negros Occidental and Aklan
    Ausan, Aisa Marie U. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2015-06)
    Zooplankton samples were collected last May and June 2014 from 20 stations in the vicinity of Kalibo, Aklan and Pontevedra, San Enrique, and Valladolid, Negros Occidental. Three hundred fifty-three (353) liters of water were filtered per station thru a 5m vertical haul of plankton net with a diameter of 30cm and a mesh size of 20μm. Overall zooplankton densities were higher in Negros Occidental, specifically in Valladolid (D=1915.3 cells/L), than in Kalibo, Aklan (D=7.2 cells/L). On the other hand, zooplankton community was most diverse in Kalibo (H’ = 2.6) compared to Valladolid (H’=1.3), San Enrique (H’=2.1) and Pontevedra (H’=1.8). Jaccard’s similarity index was highest between Pontevedra and San Enrique while lowest between Valladolid and Kalibo. In Kalibo there were four major groups of zooplankton. Most dense of these were the tintinnids (3.9 cells/L) followed by copepods (2.5 cells/L), molluscs (7xlOE-lcells/L) and polychaetes (IxlOE-lcell/L). Among the copepods Subeucalanus was the most abundant zooplankton genus. In Pontevedra and San Enrique, Negros Occidental, copepods were the most abundant group with a mean density of 205.3 cells/L and 312.1 cells/L, respectively. The relative abundance ofAcartia (36.5%) and Longipedia (22.6%) made them the dominant zooplankton genera in Pontevedra and San Enrique, respectively. Like in Kalibo, the tintinnids were also the most abundant group in Valladolid (1879.2 cells/L). Copepods followed with a mean density of 35.7 cells/L, while Polychaetes comprised only 4xlOE-l cells/L. Epiplocylis was the most abundant tintinnid in Valladolid while Xystonella in Kalibo. Varying sampling time within months and day is the possible cause of the differences in zooplankton abundance, composition, and diversity since some zooplankton species undergo diel vertical migration.
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    Evaluation of feeding performance of early siganid, Siganus guttatus, larvae fed with mixed zooplankton
    Andrade, Maria Shiela S. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1999-04)
    Siganus guttatus is an economically important rabbitfish for commercial farming. It is very important to evaluate their feeding performance particularly the effects of different diets for this larvae and to determine their growth and survival after being fed on different diets. Newly-hatched siganid, Siganus guttatus, larvae were reared in 500-L fiberglass tanks and fed either on copepod nauplii and rotifers alone or combination of both. Copepod nauplii proliferated in tanks consisted mainly of Pseudodiaptomus sp., and Acartia sp. Siganid larvae successfully commenced feeding (feeding incidence) on early stage copepod nauplii even if their abundance was low. Selective feeding ability of larvae seemed to start from day 6 and the larvae thereafter preferred to feed nauplii than rotifers. Survival of the siganid larvae was significantly higher when fed with with combination of rotifers and copepod nauplii compared to those fed with either rotifers or copepod alone. The growth of the larvae however are the same for all treatments. Results of this study suggest that coastal calanoid copepods of the genus Pseudodiaptomus sp. and Acartia sp. could be reproduced in tanks and their nauplii can be used as food for siganid larval rearing.