IMPACT RISK ASSESSMENT OF SOME PHOSPHORIC PESTICIDES BY DUNALIELLA SPP. IN BIODEGRADATION AND ENVIRONMENTAL INTERACTION OF NILE TILAPIA (OREOCHROMIS NILOTICUS)
1Central Laboratory for Aquaculture Research, Agricultural Research Center.
2Central Agricultural Pesticides Lab. Agricultural Research Center, Ministry of Agriculture, Egypt.
|Received 2/ 5/ 2017||
Accepted 7/ 6/ 2017
The present study was undertaken to investigate the degradation of organophosphorus pesticides by using living cells of Dunaliella
spp. The different components of two formulations of chlorpyrifos (dursban and pestban) was estimated and identified by using GC/ MS. Determination of the insecticides residues levels of treated, some biochemical parameters, growth performance and survival rate of Nile tilapia (Oreochromis niloticus) was studied. Nile tilapia fingerlings with an average initial body weight 20.1±0.02g were randomly distributed at a density of 15 fish in aquarium, was assigned to five treatments, with three replicates each. The first treatment was left as control, the second and the third ones were exposed to 25 and 35ppm. of dursban. The fourth and the fifth ones were exposed to 25 and 35 ppm. of pestban. Fish were fed frequently a diet of 32% CP at a rate of 3% of live body weight twice daily for 45days. The fish performance and all the biochemical aspects were affected significant (P< 0.05) by both pesticides concentration, Dunaliella supplementation, and their interaction. The obtained results showed significant (P< 0.05) reduction of total protein. The activity of aspartate amninotransferase (AST) was significantly (P< 0.05) increased in muscles of fish exposed to low and high doses of pesticides. The activity of alanine aminotransferase (ALT) in fish muscle was the highest in fish exposed to high doses, while the lowest values were observed in muscle of control fish. Tilapia fingerlings in T2 produced lower value of Creatinine, Cholesterol, Glucose and Uric acid while gave higher value of total protein and gave best value of AST, ALT in plasma. The percentage loses of dursban and pestban formulations were increased by lapse of time, and degradation rate was higher with Dunaliella
spp. It could be concluded that Dunaliella cells supplementation may reduce the harmful effect of water born pesticides in fish , which in turn improves the growth, survival, feed efficiency and decreasing their negative impact, where it gave better water quality and fish safety adverse health human effects.
Key words: Dunaliella
spp., Nile tilapia (Oreochromis niloticus), pesticides, degradation, growth performance.