African Journal of
Agricultural Research

  • Abbreviation: Afr. J. Agric. Res.
  • Language: English
  • ISSN: 1991-637X
  • DOI: 10.5897/AJAR
  • Start Year: 2006
  • Published Articles: 6849

Full Length Research Paper

Malathion toxicity in Nile tilapia, Oreochromis niloticus - A haemotological and biochemical study

Khalid Abdullah Al-Ghanim
College of Sciences and Humanity Studies P. O. Box 83, Alkharj 11942, Salman bin Abdul-Aziz University, Kingdom of Saudi Arabia. 
Email: [email protected]

  •  Accepted: 23 November 2011
  •  Published: 31 January 2012



Deliberate or accidental contamination of ponds by widely utilized organophophorous (OP) insecticides, such as malathion is a potential problem for aquaculture in tropical countries. The aim of the study was to investigate the toxic effects of malathion (0, 0.5, 1.0, 1.50 and 2 mg L−1) toxicity in the Nile tilapia (Oreochromis niloticus; 15.0  cm length and 50.0 g weight) by correlation of acute toxicity (LC50) studies with biochemical and hematological parameters. Tilapia were very sensitive to malathion (96 h LC50 2ppm). The LC50 for malathion (48 and 96 h) was 2.0 and 1.5 ppm, respectively. The fish shows quick response to malathion. In comparison with controls, sublethal levels of these pesticides led to a significant decrease (P<0.05) in final body weight. The erythrocyte count, haematocrit value and haemoglobin content of Nile tilapia were  Glycogen, and protein in fish muscle gradually decreased with increased pesticide concentrations. On the other hand, total production, net returns and profitability of reared fish decreased with increase in concentrations of pesticides.


Key words: Tilapia, malathion, toxicity, mortality, haemotological, biochemical.