Immune response of broiler chickens supplemented with pediatric cough syrup including thyme extract in drinking water against influenza vaccine

Introduction: This study was conducted to investigate the effects of thyme extract in drinking water on immune response of broiler chickens. Methods: A total of ۲۴۵-day-old broiler chicks were purchased and ۲۰ chicks were bled for determination maternal antibody and remaining chicks were divided into ۵ equal groups. Chickens of group A, B and C received ۰.۱%, ۰.۱۵% and ۰.۲% of Pediatric Cough Syrup including thyme extract respectively in drinking water for all of the experimental period. Chickens of group D were not received Pediatric Cough Syrup but vaccinated against Influenza disease. Chickens of group E were kept as control group and were not received Pediatric Cough Syrup and Influenza disease vaccine. Chickens of group A, B, C and D were vaccinated with AI-ND killed vaccine (subtype H۹N۲), subcutaneously in neck back. Blood samples were collected before vaccination as well as on days ۱۴, ۲۸ and ۳۵ after vaccination. Ten chickens of each group were bled randomly and antibody titer against influenza vaccine virus was determined by hemagglutination inhibition (HI) test. Results: The results of the present study showed that Pediatric Cough Syrup including thyme extract at ۰.۲%, increased the specific antibody response against Influenza vaccine virus compared to all groups. Conclusion: Pediatric Cough Syrup including thyme extract can improve the specific antibody response against Influenza vaccine virus.