Gorgan University of Agricultural Sciences and Natural Resources Poultry Science Journal 2345-6604 4 2 2016 12 31 Effects of Lactobacillus-Based Probiotic on Performance, Gut Microflora, Hematology and Intestinal Morphology in Young Broiler Chickens Challenged with Salmonella Typhimurium 157 165 3271 10.22069/PSJ.2016.11164.1191 EN O Ashayerizadeh Department of Animal and Poultry Nutrition, Faculity of Animal Science, Gorgan University of Agricultural Sciences and Natural Resources, Basij Square, Gorgan, Golestan, Iran B Dastar Department of Animal and Poultry Nutrition, Faculty of Animal Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran F Samadi Department of Animal and Poultry Physiology, Faculty of Animal Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran M Khomeiri Department of Food Science and Technology, Faculty of Food Science and Technology, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran A Yamchi Department of Plant Breeding and Biotechnology, Faculty of Plant Production, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran S Zerehdaran Department of Animal Science, College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran Journal Article 2016 05 16 This experiment was conducted to compare the effects of multi-strain probiotic inclusion levels on performance, intestinal morphology, gut microflora and hematological changes in Salmonella typhimurium (ST) infected broiler chickens. A total of 120 day old Ross 308 broiler chickens were distributed into 20 floor pens and reared for 10 days under 5 experimental treatments including a corn-soy basal diet with no probiotic (Control), or 0.5 g (0.05%), 1 g (0.1%), 1.5 g (0.15%) and 2 g (0.2%) probiotic/kg diet. Chickens were infected orally with ST at second day of experiment. Broilers under 0.15% of probiotic had higher body weight gain compared to other treatments. Probiotic supplementation, except at 0.05%, significantly improved feed conversion ratio. The use of 0.1 and 0.15% of probiotic reduced the population of Salmonella in ileum. The lowest heterophil:lymphocyte ratio was observed in 0.15% of probiotic, although 0.1 and 0.2% of probiotic significantly reduced this ratio compared to control group. Adding 0.15% of probiotic to the basal diet increased (P https://psj.gau.ac.ir/article_3271_37fafb3108cb6d709b852a73c666e2d0.pdf