Abstract
Lead (Pb) is one of the toxic substances equally important like arsenic. The metallic compound has extensive commercial and industrial use despite of its recognized as health hazard. The work reported here was conducted in two different phases. The first one was comprising of detection of environmental lead (Pb) concentration while the other one was involved in the therapeutic application of garlic (Allium sativum) for mitigation of Pd in lead-induced broiler chickens. The environmental samples consisted of water and soil as well as biological samples from poultry and its litter. Twenty (20) samples of each type was collected from different locations of Dhaka, Narayangonj, Norshindi, Gazipur, Chittagong and Sylhet districts. Analysis of samples was conducted by Flame Atomic Absorption Spectrophotometric Analysis (FAAS). The results of analysis of variance of mean Pb-concentration in different samples collected from different locations differed significantly (P<0.05). The highest mean values of Pb-accumulation in drinking/ground water, industrial waste water and agricultural soil samples collected from Norshindi was detected as 0.064±0.021ml/kg, 95.735±9.593 ml/kg and 119.033±9.853 mg/kg, respectively. On the other hand, the surface water was found to be highly contaminated (0.622±0.096ml/kg) with Pb obtained from Narayangonj. As regards biological samples, the highest natural accumulation of (0.096±0.948ml/kg) of Pb was found in chicken bone collected from Narayangonj while the lowest concentration (Pb) was detected in muscles (0.034±0.006ml/kg) obtained from Sylhet. The natural accumulation of Pb was highly and significantly (P<0.001) present in egg shell (0.221±0.032ml/kg) compared with to the yolk (0.039±0.010ml/kg) and albumen (0.026±0.003 ml/kg) that was collected from Norshindi. The natural accumulation of Pb in poultry meat and eggs was found at tolerance level but the cumulative load may be of serious health hazard. The poultry litter was also detected to be significantly (P<0.05) a major toxic agent for environmental degradation due to the presence of wide range of Pb at different location of selected districts. In the second phase, 350 commercial broiler chickens were grouped into five such as To, T1, T2, T3 and T4 consisting of 70 birds each where To served as control. T, was provided with lead acetate at 100mg/kg body weight, T2 had 100mg/kg lead acetate + 1% garlic supplement, T3 was fed with 100mg/kg lead acetate + 2% garlic supplement and T4 had 100mg/kg lead acetate + 4% garlic supplement. The experiment was aimed at determination of prevention of accumulation of Pb in body tissues as well as changes in hemato-biochemical parameters, carcass quality, weight gain and feed conversion in Pb-toxicity (100mg/kg) induced broilers with garlic supplemented with different doses (1%, 2% and 4%) fed for 42 consecutive days. Naturally occurring anti-oxidant "garlic" was found to be capable of enhancing elimination of Pb in lead-exposed chickens. Reduction in tissue lead concentrations were significantly (P<0.05) higher in birds provided with 2% garlic supplement (T3) than such other group having provided with 1% and 4% garlic supplements (T2 and T4). Garlic was also found to be able for effective revert towards the normal value of RBC (TEC), hemoglobin content, PVC and differential leukocytes counts. Analysis of variance of data on biochemical changes, such as BUN, uric acid, cholesterol, triglycerides, HDL, LDL, ALT, AST, creatinine and serum glucose values corresponding to the different treatments different significantly (P<0.01). The most significant response was recorded in 2% garlic supplemented diet with lead acetate group (T3). The protective action of garlic against lead (Pb) toxicity could be attributed to the antioxidant action of sulphydral groups present in garlic. The potential action of garlic towards reverting to hematological and biochemical values close to its normal level coincided with their function as chelating agents. The deleterious effect on health of chicken due to Pb-toxicity was possibly mitigated through, as recorded in the present study, the consumption of certain percentages of garlic indicated that it might be considered as the protective regimen in care of lead (Pb) toxicity.