title: Probiotic level effects on growth performance, carcass traits, blood parameters, cecal microbiota, and immune response of broilers.
abstract: Probiotic effects on growth performance, carcass traits, blood parameters, cecal microbiota, and immune response of broilers were studied. Two hundred one-day-old male chickens were allocated to one of five treatments (four replicates of 10 birds per treatment): control, and the same control diet supplemented with 0.005%, 0.01%, 0.015% and 0.02% probiotics. Probiotics in feed at 0.01% or higher levels of supplementation improved body weight gain (+12%) and feed conversion rate (-5%) compared with the control. There were no effects on carcass traits, but the relative weights of drumsticks and wings showed increasing and decreasing linear responses, respectively, to probiotic supplementation level. Blood plasma glucose and albumin contents linearly increased (from 167.1 to 200.5 mg dl-1, and from 1.70 to 3.25 g dl-1) with increasing probiotic supplementation. Triglycerides and cholesterol contents were lower in probiotic supplemented treatments (average contents 71.3 and 125.3 mg dl-1 vs. 92.6 and 149.9 mg dl-1 in the control). Probiotics decreased cecal Escherichia coli counts, but had no effects on immunity related organs or immune response. The linear trends, either positive or negative, observed in many of the parameters studied, suggest that more studies are needed to establish the optimal concentration of probiotics in broiler feed.
authors.affiliation: Department of Animal Science, Rasht Branch, Islamic Azad University, Pole-Taleshan Street, 41335-3516 Rasht, Iran, Islamic Azad University, Islamic Azad University, Rasht , Iran.
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Pourakbari
authors.affiliation: Department of Veterinary Science, Rasht Branch, Islamic Azad University, Pole-Taleshan Street, 41335-3516 Rasht, Iran, Islamic Azad University, Islamic Azad University, Rasht , Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Seidavi
authors.affiliation: Department of Veterinary Science, Rasht Branch, Islamic Azad University, Pole-Taleshan Street, 41335-3516 Rasht, Iran, Islamic Azad University, Islamic Azad University, Rasht , Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Asadpour
authors.affiliation: Department of Animal Production, University of Córdoba, Ctra. Madrid-Cádiz, Km 396, 14071 Córdoba, Spain, Universidad de Córdoba, University of Córdoba, Department of Animal Production, Córdoba , Spain.
authors.forename: Andrés
authors.initials: A
authors.lastname: Martínez
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002432:Cecum / Q000382:microbiology*; D002645:Chickens / Q000097:blood / Q000254:growth & development*; D019587:Dietary Supplements; D000069196:Gastrointestinal Microbiome; D008297:Male; D019936:Probiotics / Q000008:administration & dosage*; D015430:Weight Gain; D014921:Wings, Animal / Q000254:growth & development
chemical_list: D001786:Blood Glucose