Prevention of Salmonella Colonization in Neonatal Broiler Chicks by Using Different Routes of Probiotic Administration in Hatchery Evaluated by Culture and PCR Techniques

The effects of various methods of probiotic administration in hatchery and on prevention of Salmonella enteritidis (Se) in broiler chicks was investigated. A total of ۱۵۰ Salmonella free day old chicks (Ross ۳۰۸) were assigned to five experimental groups including control and four in-hatchery probiotic administration method groups comprised of: in ovo injection, oral gavage, spray and vent lip application. Each group was comprized of ۳۰ chicks. The chicks were challenged by ۸ Log CFU Se using oral gavage on ۲ days of age. At ۱ and ۷ days of post-challenge (PC) ۱۵ birds per experimental group were sampled for Se recovery through either one of culture or culture based PCR techniques. Administration of probiotics reduced the number of Se colonized chicks, compared with control as evaluated through either culture or PCR method. These reductions were significant for all the administration routes (P< ۰.۰۵), except for the ۱ day PC, evaluated by culture method (P> ۰.۰۵). Furthermore probiotics were capable of reducing the number of colonized chicks from day ۱ to day ۷ PC. Vent lip method was evaluated as the most effective route of probiotic administration in prevention of Se colonization, not significantly different from either spray application in day ۱ of PC group or from other administration methods in the day of ۷ PC (P> ۰.۰۵). PCR method was more reponsive in detection of Se as compared to traditional culture method. Administration of probiotics in hatchery finally resulted in reducing the colonization of Salmonella in the alimentary tract of chicks.