The Evaluation of the Efficiency of Different Routes for the Administration of Immune Complex IBD Vaccine in Broilers

The preferential method to enjoy the benefits of Immune- complex vaccines is the in-ovo injection which needs very complex and advanced injection machines. These machines are not yet widely available. In this study، the function of an Immune- complex vaccine was compared by using two methods. The fist method was the In-ovo injection in the 18th day of incubation period and the second one was the Sub-cutanous vaccination in the day-old chicks. For this purpose four parameters including mean final weight، antibody response، bursa to body weight ratio and the grade of microscopic injuries within the bursa of fabrisius were measured. The results showed that the method of vaccination in induction of ELISA antibody response in (KPL) except for the 18th and 25th days of age did not cause any significant difference between the two vaccinated groups. In the samples for the vaccinated 32 day old chickens، bursa to body weight ratio was significantly (p<0. 05) lower than control group، but there was no significant difference between the two vaccinated groups. The histopathological study of the bursa samples indicated a significant difference (P 0/05) in microscopic injuries grade between the vaccinated groups and the control group، but this difference between the vaccinated groups except for the 8 days old chick’s samples did not show any significant difference. The amount of final weight in the end of the study between the two vaccinated groups and also between the vaccinated groups and the control group showed a significant difference (P 0/05). It can be concluded that the vaccination with the subcutaneous method in day-old chicks using the function of Immune-complex vaccine can be considered as reliable in-ovo method for the administration of immune-complex vaccines.