The effects on haematology of 48 rabbits (24 of each sex) were studied by administering cypermethrin (CY) intraperitoneally. In each sex, animals were divided into four equal groups A, B, C and D. The animals in groups B, C and D received low (50 mg.kg^-1 b. wt.), medium (100 mg.kg^-1 b. wt.) and high (150 mg.kg^-1 b. wt.) CY doses, respectively in mustard oil. Group A served as control and each animal received equivalent volume of mustard oil. The animals received five CY treatments (d 1, 8, 15, 22 and 29). Blood samples with anticoagulant from all animals were collected prior to experiment (day 0) and after every treatment for haematological studies. The total erythrocyte count (TEC), haemoglobin (Hb) concentration and packed cell volume (PCV) were analyzed at each experimental period and erythrocyte indices were calculated. During the experiment, significant increase in mean corpuscular volume (MCV) and significant decrease in TEC, Hb concentration and mean corpuscular Hb concentration (MCHC) were found in the male rabbits treated with CY especially at higher doses, while the decrease in these parameters in the female rabbits was non-significant at all dose levels and time periods. Thus, it was concluded that macrocytic hypochromic anaemia was induced in the male rabbits due to CY treatment, but not in the females at the dose levels administered during the study.

Key words: Rabbits, cypermethrin, anaemia.