This study was conducted to investigate the sub-acute toxic effects of Chlorpyrifos, using male rabbits as an animal model for mammals. Lara-909 (containing 50% chlorpyrifos) was given @71.5 mg chlorpyrifos /kg body weight per day orally for 14 days. Blood samples were collected at day 0, 7 and day 15 for analysis. Intoxicated rabbits showed dullness, anorexia, dehydration, excessive salivation, muscle contractions, twitching with staggering gait and progressive loss of weight. Mortality over

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... days was 83%. In comparison to control group, mean values of Hb, MCH, MCHC and creatinine were significantly increased while lymphocyte count and albumin were significantly decreased on day seven of the experiment. The mean values of total protein, globulin, glucose, ALT, AST, and BUN did not differ significantly from control values. Page209 2002). Experimental studies have revealed that chlorpyrifos has dose related effects on liver, testes, spermatozoa, and nervous system besides causing wide ranges of clinico-pathological alterations (Akhtar et al., 2009; Solati et al., 2012) . Since chlorpyrifos is widely used as insecticide by agriculturists in Kashmir valley, it remains a potential health hazard for animals and humans. Hence a study was conducted to study pathological effects of sub-acute chlorpyrifos toxicity in an animal model using rabbits. Materials and Methods A total of 12 gray giant male rabbits (1 to 1.5 Kg weight) were maintained in cage system under standard laboratory conditions. These were acclimatized to rearing conditions for one week before start of the experiment. The experimental protocol was approved by the Institutional Animal Ethics Committee. The rabbits were randomly allocated to two groups of six rabbit's each-Group-I (control) and Group-II (Chlorpyrifos intoxicated). For inducing toxicity, Lara-909 (containing 50% chlorpyrifos) was administered orally @71.5 mg chlorpyrifos /kg body weight per day for 14 days (Fikes, 1992) . Blood samples were collected at days 0, 7 and day 15 for hematological and biochemical analysis. Hematology was done using MS4 multi-species haematological analyser (MELET SCHLOESING Laboratoires-9 Chaussee Jules Cesar-Evolic 402-95520 OSNY France). Glucose, total protein, albumin, aspartate transaminase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN) and creatinine were analyzed using diagnostic kits (Aspen Laboratories Pvt. Ltd, Rapid Diagnostic Group of Companies, Karnal Road Industrial Area, Delhi, India) and semi-automatic blood chemistry analyser (model ERBA CHEM-PRO). Data were processed by SPSS statistical software. The significant differences between control and Chlorpyrifos intoxicated groups was determined using t-test. ANOVA followed by DMRT was used for multiple comparisons. The differences were regarded significant at p <0.05. Results and Discussion The clinical signs observed in chlorpyrifos intoxicated rabbits (group II) were dullness, depression, partial to complete anorexia, lacrimation, bradypnea, mydriasis, muscle contractions, staggering and prostration. Rabbits fell suddenly revealing uneasiness and paddling of legs followed by unconsciousness with urination and defecation before death. Out of six intoxicated rabbits only one survived after 14 days experimental period. The clinical signs observed in present study were in concordance with those reported by Mehta et al. (2006) in calves. However, Mansour and Mossa (2010) did not observe any appreciable change in rats. The nervous signs observed prior to death might be attributed to acetyl cholinesterase (ACh) inhibition leading to accumulation of ACh in synaptic junctions (Karanth et al., 2006) . Recumbency, wry-neck, and intermittent rolling on back, as seen in the present study, has been observed Page213 Conclusion Subacute chlorpyrifos intoxication in rabbits caused progressive clinical effects and progressive loss of body weight with 83% mortality over a period of 14 days. The hematological alterations and biochemical parameters were non-diagnostic except decreased lymphocyte count and albumin, and increased Hb, MCH, MCHC and creatinine on day 7 as compared to control group. It is suggested that such changes may have long lasting post-effects in survivors, if any.