The concern over detrimental effects of chemical pesticide residues on the environment has
enhanced the use of bio-pesticides that may also negatively impact aquatic ecosystems. The present study
determined the 96‐h 50% lethal concentration (LC50) of the NeemAzal (containing 10 gL-1 azadirachtin)
bio-pesticide and evaluated the sub-chronic effects of its sublethal doses (0.12, 0.24 and 0.36 mgL -1 )
on blood and biochemistry of common carp (Cyprinus carpio) with an average weight of 14.20±2.07 g.
The 96-h LC50 was found to be 1.19 mgL-1 of the pesticide. As NeemAzal content increased, the leukocyte
count (WBC) and the level of creatinine (Cr), urea (BUN), cholesterol, glucose (GLU), neutrophils
and aspartate aminotransferase (AST) elevated (p<0.05). Also, total proteins (TP), triglyceride (TG),
alkaline phosphatase (ALP), hemoglobin (Hb), erythrocyte count (RBC), lymphocytes and hematocrit
(Hct) decreased (p<0.05) with increasing toxin doses. Insignificant difference was found between the
mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV) and mean corpuscular hemoglobin
concentration (MCHC). Levels of eosinophils, basophils, monocytes, alanine aminotransferase (ALT)
and albumin (ALP) of the exposed and controlled fish were also insignificant (p>0.05). The present
investigation suggests that long-term exposure to NeemAzal can affect the hematological and biochemical
parameters and can be harmful to C. carpio