Effect of garlic on growth performance, intestinal villus morphology and Serum Antibody Titers against Newcastle and Avian Influenza Vaccine in broiler chickens

To investigate the effect of dietary garlic powder (Allium sativum) on broiler performance, intestinal morphology and serum antibody titer against Newcastle and Influenza Vaccine (H9N2), 180 one day old Ross chicks were purchased and randomly divided into four equal groups(each group contain 45 chickens in 3 replicates). Group 1 as control group received basal diet, groups 2, 3 and 4 received diet supplemented with 0.2%, 0.6% and 1% garlic powder, respectively. Chicks were raised on floor-pen under standard conditions until day 42 of age. At days 14, 28 and 42 of age, Chickens were weighed, feed intake was calculated and FCR was measured. Blood samples were taken via wing vein from ten birds of each group on days 14, 28 and 42. The sera were assayed for antibody against NDV and AIV by HI (4 HA unit) test and then 6 chicks of each group were randomly selected and samples from Duodenum, Jejunum and Ileum were collected for morphometric analysis. The findings of this study showed that growth factors of broilers (feed intake, body weight and FCR) and antibody titer against Newcastle and Influenza Vaccine were not markedly influenced by garlic. In addition, increasing dietary garlic in lower level (0.2% and 0.6%) had not significant effect on intestinal morphology parameters but higher level (1%) of garlic in ration had adverse effect on villous height and lamina properia thickness.