Subchronic toxicity effects of the residual level of chlorpyrifos on nile tilapia (Oreochromis nilotica, linnaeus) with emphasis on the histology of specific organs.
Date
4-1999
Degree
Bachelor of Science in Biology
Major Course
Major in Cell Biology
College
College of Arts and Sciences (CAS)
Adviser/Committee Chair
Pablo P. Ocampo
Abstract
A study on the subchronic toxicity effects of residual level of chlorpyrifos [0,0- diethyl O-(3,5,6-trichloro-2-pyridil) phosphorothioate] on male Nile tilapia (Oreochromis niloiica, L.) was conducted. The fishes were exposed to varying concentrations of 0.01 mg/L, 0.001 mg/L and 0.005 mg/L chlorpyrifos, an organophosphorothioate pesticide, for a 15-day period after two weeks of acclimatization. Behavioral and morphological observations include erratic swimming patterns of the fishes, and presence of black spots and streaks to those stressed individuals. Liver, spleen, and gonads were extracted from the animals. These were then processed using histological techniques and were examined under light microscopy. The treatment with the lowest Chlorpyrifos concentration (0.001 mg/L) exhibited the least liver tissue damage, showing signs of necrosis, inflamed cells, and cell debris. At 0.005 mg/L concentration, tissue section of animals exhibited moderate damage of the same type as that of the lower concentration; a more advanced damage was observed, however. At high level of treatment (0.01 mg/L), complete necrosis was found on liver tissues; retardation of spermatogenesis of the testes was also observed. This treatment was also characterized by the high mortality rate of 80%. No effect on the spleen was observed. Statistical analysis also showed significant effect in gonad and liver relative weights.
Language
English
Location
UPLB Main Library Special Collections Section (USCS)
Call Number
Thesis
Recommended Citation
Carpio, Jovy Aura A., "Subchronic toxicity effects of the residual level of chlorpyrifos on nile tilapia (Oreochromis nilotica, linnaeus) with emphasis on the histology of specific organs." (1999). Undergraduate Theses. 10875.
https://www.ukdr.uplb.edu.ph/etd-undergrad/10875
Document Type
Thesis
