Lead poisoning in aquatic animals is of special importance, as is also true for all livingcreatures. Alicin, one of the main active components of garlic, is expected to play a protective role against lead poisoning, due to its abundant sulfur amino acids. This research studied the toxic effects of lead in Common Carp focusing on blood serum enzyme activities. The study focused on five groups each including 46 Common Carp (100±10g). The groups 2-5 received lead acetate at 7mg/L for 10 days. Group 3 received 5mg allicin/KgBwt; and Group 4 received daily amounts of 10mg allicin/KgBwt, beginning 5 days before lead acetate was added. Group 5 received the same as Group 4, but received allicin for the same period as it received lead acetate. At the end of
the experimental period a measurement was made of serum enzymes including GGT, ALT, AST, LDH and ALP. The studied parameters in Group 2, which was exposed to lead, were significantly higher when compared to the Control Group (p<0.001). The enzyme activities in groups receiving allicin (Groups 3-5) were significantly, and dose dependently, less than those of Group 2. However, no significant differences were observed between Groups 4 and 5. The results of the present research suggest a potent effect for allicin in alleviating tissue injuries following lead poisoning.