Effects of acetylcholinesterase-inhibiting chemicals on Nile tilapia (Oreochromis niloticus Linn) at pre-and post-hatching stages of development

Issue Date

10-2009

Abstract

The toxic effect of carbaryl and chlorpyrifos (CPF) insecticides were evaluated on the early development stages of Oreochromis niloticus Linn. A number of morphological abnormalities were observed during the course of the experiment. A cute exposure (24-hour LC50) experiment determined the mortality pattern of newly hatched ). Niloticus exposed to different concentrations of the toxicants. Median hatchability performance (HC50) of eggs was also estimated. The 24-Hour LC50 estimated for carbaryl and CPF were 6.07 mg/L and 22.39 ug/L, respectively. The estimated HC50, values were 6.04 mg/L for CPF and 21.15 ug/L for CPF. Sub-chronic exposure to residual levels of both test materials resulted in high inhibition levels of AChE activity. Analysis revealed significant differences in AChE activity among O. niloticus exposed to either carbaryl (KW=11.58, P < 0.05) or CPF (KW=12.243, P<0.05) at different lengths of exposure period. For both test materials, the peak of AChE activity was recorded on the 7th day of exposure. AChE activity, however, was found not proportional to the length of exposure period. AChE activity in the test fish recovered on the 11th day of the recovery period, with about 92% recovery for the carbaryl-exposed and about 93% for the CPF-exposed.

Source or Periodical Title

Philippine Entomologist

ISSN

0048-3753

Volume

23

Issue

2

Page

155-173

Document Type

Article

Frequency

semi-annually

Physical Description

graphs

Language

English

En – AGROVOC descriptors

OREOCHROMIS NILOTICUS; TILAPIA; PESTICIDE EXPOSURE; CARBARYL; CHLORPYRIFOS; ACETYLCHOLINESTERASE

This document is currently not available here.

Share

COinS