02764cas a2200253 a 450000500170000000800410001703500150005810000120007324500690008526000520015430000100020649000270021650001530024350200570039652017160045365000120216965000170218170000340219870000450223270000570227771000520233481000590238685600650244520260818084328.0110920s1989    th uu|m rtt   0|  a1eng d  a.b100259351 aXu, Hui12aA comparison of tilapia production in pond, cage and pen culture  aBangkok :bAsian Institute of Technology,c1989  a70 p.1 aThesis ;vno. AE-89-41  aA thesis submitted in partial fulfilment of the requirements  for the degree of master of science, School of Environment, Resources and Development   aThesis (M.Sc.) - Asian Institute of Technology, 1989  aAn experiment was conducted for a period of 4 months to compare the  production of tilapia <Oreochromis niloticus) cultured in open pond, cage and  pen in 3 semi-intensive ponds. Chicken manure were applied to the ponds at  the rate of 250 kg chicken manure (dry weight> I hectare/week and urea was  added to make up the desired N:P ratio of 5:1 throughout this experiment.  Fish production, growth and nutritional values of pond inputs, pond water  quality, detritus quality and organisms were determined during the experiment.  The mean daily fish weight gain in pond, cage and pen were 0 .94, 0.93 and  0.97 g/fish/day with mean survival of 90.5%, 93.9% and 90.3%, respectively. The  extrapolated total net yield of Nile tilapia was 5586 kg/ha/yr in the pond,  5307 kg/ha/yr in the cage and 5953 kg/ha/yr in the pen. However, t here was  no significant difference for fish production and survival rate in those 3  treatments.  Analysis of fish stomach contents showed that similar fish diet was  found in three cultural systems. They consumed mainly phytoplankton, of  which the dominant species were Microcystis sp and Anabaena sp. The ranges of  pond water quality were as follows: total ammonia 0 .38 ±0.10- 1.61 ±0 .15 mg/l;  temperature 28.1-31.4 °C ; pH value 8.10-9.12 ; dissolved oxygen from dawn to  sunset 2. 1 ±0.4-8.6 ±0.5 mg/l. The phytoplankton biomass in three ponds  increased with time and the highest biomass was 19.10 ±7.02 mg/l (dry wt). · The  mean detrital deposition to pond bottom estimated for dry matter and organic  matter were 333.5 ±11 3.4 g/ m2 /day and 292.72 ±105.33 g/m2 /day, respectively.  The mean deposition of chlorophyll-a in detritus was 52 ±4.5 mg/m2 /day.  0aTilapia 0aFish-culture1 aLin, Chang Kwei,eChairperson1 aLittle, David C.,eExamination Committee1 aKnud-Hansen, Christopher F., eExamination Committee2 aThe British Council (TCTA), eScholarship Donor2 aAsian Institute of Technology.tThesis ;vno. AE-89-41  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B17892