Pyrethroid-induced melanomacrophage centers (MMCs) formation among Nile tilapia (Oreochromis niloticus Linn) with emphasis on pigment composition

Date

2-2008

Degree

Bachelor of Science in Biology

Major Course

Major in Zoology

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Pablo P. Ocampo

Abstract

PYRETHROID- INDUCED MELANOMACROPHAGE CENTERS (MMCs) FORMATION AMONG NILE TILAPIA (Oreochromis niloticus Linn.) WITH EMPHASIS ON PIGMENT COMPOSITION

Adviser: Dr. Pablo P. Ocampo

ABSTRACT This study intended to evaluate the pigment composition of melanomacrophag centers (MMCs) in Oreochromis niloticus Linn, exposed to low levels of cypermethrin and deltamethrin through a time course experiment. The dose levels used were 1.6 ug/L of cypermethrin and 15.0 ug/L of deltamethrin. Observation periods were at P, 7th 11th and 15th day of exposure to the toxicants. Measured parameters include body weights, relative weights of liver and spleen, MMC count, MMC size and pigment composition. Analysis of weights indicated no significant differences among body weights and relative spleen weights of treated groups for cypermethrin and deltamethrin. Relative liver weights of cypermethrin exposed individuals showed significant differences among different exposure periods (F value=4.726, P<0.05). The same pattern was observed for fishes exposed to deltamethrin (F value=20.137, P<0.05). Cypermethrin-exposed fishes did not form MMCs in the liver. Formation of MMCs was observed in the 751 observation period using deltamethrin. Exposure to 1.6 ug/L of cypermethrin induced significant number of splenic MMCs (KW value= 15.216, P<0.05). Exposure to 15.0 ug/L of deltamethrin also induced significant proliferation of splenic MMCs (KW value= 4.866, P<0.05). However, sizes of splenic MMCs formed from exposure to either cypermethrin or deltamethrin were not significantly different from that of the control group. Hemosiderin and lipofuscin were the only pigments accounted for this study due to scarcity of melanin pigments. Pigment compositions for cypermethrin and deltamethrin-treated fishes were not significantly different and were highly composed of lipofuscin.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

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