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UPV Theses and Dissertations

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Degree: search.filters.degree.Bachelor of Science in BiologyKeyword: search.filters.keyword.Fish

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    Effects of high and low protein diets on the gut evacuation rate of Tilapia nilotica
    Andrada, Bryan Andrew S. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1999-03)
    Gut evacuation rate of young Nile tilapia, Tilapia nilotica fed commercial pelleted diets containing high or low protein diet were determined in the laboratory. The decline in gut fullness of the fish with time was examined at low and high protein diets. Two mathematical models were used to express the decline in gut fullness of the fish with time. Fish fed the low protein diet followed more closely the linear model while those fed the high protein diet followed the logarithmic model. The level of protein resulted in different gut evacuation rates (GER), expressed as coefficients b of the gut fullnesstime curve. GER values were higher in either linear or logarithmic models for fish fed low protein diet than for those fed high protein diet.
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    A survey of the catch composition of fyke nets in the Iloilo river
    Andrada, 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.
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    Comparative growth rates and gross morphology of hybrid catfish Clarias gariepinus (female) x Clarias macrocephalus (male)
    Agase, Mark Christian A. (Division of Biological Sciences, Bachelor of Science in Biology, University of the Philippines Visayas, 2004-03)
    Catfishes are among the groups that has been considered economically important fishes in the Philippines and in other countries. The freshwater catfish Clarias macrocephalus is native to the Philippines but it is becoming scarce in many natural habitats. It is a favorite food dish due to its tender and delicious meet. Aquaculturists these days focus more their attention to the culture of exotic species like Clarias gariepinus and Clarias batrachus that in turn resulted to the near extinction of the native species. There is therefore a need to undertake a breeding program involving this native catfish and other exotic species.A 12-week study was conducted to compare the growth rates of the hybrid catfish C. macrocephalus (♂) X C. gariepinus (♀) in natural ponds and laboratory rearing conditions. In addition, the length-weight relationship was also determined. Gross morphology was also noted in the experiment.Results showed that the trend for SGR of the hybrid in natural pond and laboratory rearing conditions from weeks 2 to 12 is decreasing. Continued feeding of the hybrids on artificial diets results in poor fish growth. T-test revealed that there is a significant difference on the SGR for both the length and weight with hybrids in natural pond rearing conditions being consistently higher than the laboratory set-up.From the linear regression equation, there was no homogeneity of regression, coefficients, or slopes in the mean body lengths (MBL) and mean body weights (MBW) of me hybrids in the natural pond and laboratory rearing condition. It simply means that there is a significant difference on the growth rates of the hybrid as to the type of environment they are reared. The product-moment correlation showed that there is a linear relationship between the length and the weight of the hybrid fish, 7.9305378 X 104 being the constant. Gross morphology of the hybrids includes the appearance of a trident-shaped occipital process, which was not pointed and narrow as in the case of the parent C. gariepinus. A turtle shell-like design arranged bilaterally characterizes the dorsal side of the head. A modification of the dorsal fin was also noted as to the presence of the adipose fin at the posterior end of the dorsal fin, which was about 3-5 mm in length.