Maintaining the balance of intestinal microbiota of broilers with probiotics after antibiotic therapy

• Grant number: 11/20842-0
• Support Opportunities: Regular Research Grants
• Duration: April 01, 2012 - March 31, 2014
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: José Fernando Machado Menten
• Grantee: José Fernando Machado Menten
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Adriana Ayres Pedroso ; Marcio Rodrigues Lambais

Abstract

The aim of the study is to will evaluate the efficiency of addition of a probiotic in broiler diets in the maintenance of the structure of the intestinal microbiota following antibiotic therapy. The chickens will be raised in floor pens during from 1 to 42 days of age. The birds will be allocated in a completely randomized experimental design with four treatment and nine replicates. The treatments are: Basal diet without probiotics; basal diet + probiotic; basal diet + antibiotic therapy and basal diet + probiotic + antibiotic therapy. The probiotic Bacillus subtilus will be provided in the feed during the entire experimental. The antibiotic therapy will consist of a Gram positive and a Gram negative antibiotic in the water at 21 days of age. For the determination of the performance variables, the animals will be weighed at 7, 14, 21, 35 and 42 days of age and feed intake recorded. At 26, 28 and 30 days of age birds from four replicates per treatment will be used for analysis of gut microbiology. Three birds from each pen will be sacrificed to collect material from the mucosa of the ileum and cecum. The composite sample of DNA will be extracted and the specific fragments of V1-V3 region of 16S rDNA microorganisms representing the domain Bacteria will be amplified. These will be submitted to the DGGE technique, which assesses changes in the structure of the intestinal community, and quantitative PCR to quantify the main components of the intestinal tract of broilers as Bifidobacteria, Lactobacillus and Clostridium. (AU)