Survey on the changes of specific antibody titre against Newcastle disease vaccine in broiler chickens after receiving of biohebal® feed supplement (contains thyme and garlic extracts)

33000 one day-old broiler chickens were purchased and divided into 2 equal groups. Chickens of groups A received 200 ml of Bioherbal® supplement in 1000 liter of drinking water for all the period. Chickens of group B did not receive Bioherbal® supplement as control group. Chickens of 2 groups were vaccinated against Newcastle disease with Vitabron through spray on 1th days, with B1 strain intraocularly on 9th days, with Nobilis ND Clone 30 on 20th days, and with LaSota Strain in drinking water on 30th days.35 chicks of each group were bled randomly and blood samples were collected before vaccination as well as on last day of the period and antibody titer against Newcastle disease vaccine was determined by HI test. The results of this study showed that receiving of 200 ml of Bioherbal® supplement in 1000 liter of drinking water could increase the specific antibody titer against Newcastle disease vaccine compared to the control group(p >0.05).