efficiency of early (in hatchery) probiotic administration methods against salmonella colonization in japanese quail

total of 270 quail fertile eggs were set in hatchery. experimental groups including: negative control (neither received probiotic treatment nor challenged by salmonella), positive control (challenged by salmonella but not probiotic treatment) and 7 in hatchery administration methods: in ovo injection, spray, oral gavage, cloacal drinking (cloacal inoculation), cloacal drinking – in ovo injection, cloacal drinking– spray and cloacal drinking – oral gavage. each group included 15 day old chicks. all chicks were challenged by 1.75104 cfu / ml salmonella eneteritidis using oral gavage except negative control 36 h post probiotic treatment. 12 chicks from each group were euthanized by co2 inhalation 24 h postchallange. cecal tonsil aseptically collected and colonisation of salmonella were probed using culture technique. the spray method significantly reduced salmonella enteritidis colonization (p<0.01). on 8th day higher bw were observed in oral group (p<0.05). the administration methods were significantly effective on the liver and bursa of fabricius weight (p<0.05). in conclusion probiotic administration using spray on quails day old chicks were the most effective in prevention of salmonella colonization.