genoToxic EFfects of butataf herbicide oN NILE TILAPIA
Ashraf A. Ramadan
Genetics and Breeding Department, Central Laboratory for Aquaculture Research, Agricultural Research Center. Egypt.
Received 5/ 4/ 2010
Accepted 10/ 5/ 2010
This study was carried out to assess the capability of butataf herbicide in inducing cytogenetic damage of Nile tilapia, Oreochromis niloticus. The 96 hours half lethal concentration (96 hr LC50) of the butataf herbicide determined for the adults O. niloticus was 0.2 ppm. The field concentration of this herbicide was 0.004 ppm which corresponds to 1/50 of the LC50. The present experimental assay was carried out on the 30 day of exposure to the 1/100, 1/50, 1/25 LC50 and 1/10 LC50 which were used to study the effect of butataf on the rate of cell proliferation as well as the possible chromosomal aberrations of Nile tilapia genome. The results revealed that the butataf herbicide decrease of the rate of cell proliferation (low mitotic index). The rate of cell proliferation reached 1.1% in treated Nile tilapia with the highest dose 0.02 ppm of butataf which compared with the control groups (6.7%). In addition, different types of chromosomal aberrations; i.e., fragments, chromatid breaks. Stickiness, hypo and hyperpolyploidy were observed. The study concluded that butataf may have a genotoxic effect on tilapia fish.
Keywords: genotoxicity, Nile tilapia, butataf herbicide, mitotic index, chromosome aberrations.