assessment of the effects of dietary supplementation with alliacin (alcoholic extracts of garlic, onion and leek) on the immune system of broiler chickens (ross-308)

Allium genus includes 550 species, few of which are important as medicinal plants, among them are onion (allium cepa l.), garlic (allium sativum l.) and leek (allium ampleoprasam var. kurrat) are pointed out (1). several studies indicated the effect of garlic, onion and leek on the immune system (2,3). alliacin is an herbal compound containing the alcoholic extracts of garlic, onion and leek. alliacin was added to a ratio of 1, 2 and 4 ml per l of drinking water in different experimental groups to evaluate the effect of alliacin on the immune system, antibody titer changes due to vaccination against avian influenza h9n2 and newcastle disease as well as the weight of the thymus and bursa of fabricius relative to body weight. the results of this study revealed that although in the groups receiving alliacin, the weight of bursa of fabricius and thymus at the end of the rearing period were higher than the control group, however, in the evaluation of bursa of fabricius and thymus weight in relation to body weight, a significant difference was not observed (p > 0.05). also, there was no significant difference in the avian influenza h9n2 and newcastle disease antibody titers of the alliacin-receiving groups with the control group (p > 0.05). it could be concluded that dietary supplementation with alliacin hadsignificant effect on increasing serum antibody titers due to avian influenza (h9n2) and newcastle disease vaccination and the weight of lymphatic organs (bursa of fabricius and thymus).