Abstract
The leaves of Azadirachta indica plant was screened for haematological, toxic and serum enzyme activities in rats. Twenty rats were used and were grouped into 4 of 5 rats each. Group 1 was the negative control group administered distilled water. Groups 2, 3, and 4 were the treatment groups received 200, 400 and 800 mg/kg body weight of the A. indica extract respectively. The rats were dosed for 14 days, thereafter were sacrificed and blood collected by cardiac puncture for analysis. The effect of A. indica extract was checked on haematological parameters and serum enzymes activities. All results in treatment groups were compared with the normal control at statistical confidence of 95% (p<0.05). There was progressive reduction of haematological parameters as the dose of the extract increased from 200, 400, to 800 mg/kg body weight. Haematological parameters, PCV, RBC, Haemoglobin showed decrease value which was not statistically significant at (p<0.05). Total leukocyte count, showed progressively elevation by the extract though not statistically significant. Differential leukocyte count indicated very mild lymphocytosis neutropeania, monocytopeania and eosinopeania which were not statistically significant. Clinical biochemical parameters, A. indica extract demonstrated normal levels of the serum enzymes (AST, ALT and ALP) though there was slight decrease in a dose dependent fashion.Total protein was within normal range. The normal MCV, MCH and MCHC values suggests normocytic normochromic anaemic condition. The extract of A. indica is safe to blood cells, liver and kidney marker enzymes at dose < 800 mg/kg body weight.

Key words: Azadirachta indica ,Toxicity, Serum enzyme, Haematology.