title: Effects of the antibiotic growth promoters flavomycin and florfenicol on the autochthonous intestinal microbiota of hybrid tilapia (Oreochromis niloticus ♀ × O. aureus ♂).
abstract: The 16S rDNA PCR-DGGE and rpoB quantitative PCR (RQ-PCR) techniques were used to evaluate the effects of dietary flavomycin and florfenicol on the autochthonous intestinal microbiota of hybrid tilapia. The fish were fed four diets: control, dietary flavomycin, florfenicol and their combination. After 8 weeks of feeding, 6 fish from each cage were randomly chosen for the analysis. The total number of intestinal bacteria was determined by RQ-PCR. The results showed that dietary antibiotics significantly influenced the intestinal microbiota and dramatically reduced the intensity of total intestinal bacterial counts. The intensity of some phylotypes (EU563257, EU563262 and EU563255) were reduced to non-detectable levels by both dietary antibiotics, while supplementation of florfenicol to the diet also reduced the intensity of the phylotypes EU563242 and EU563262, uncultured Mycobacterium sp.-like, uncultured Cyanobacterium-like and uncultured Cyanobacterium (EU563246). Dietary flavomycin only reduced the OTU intensity of one phylotype, identified as a member of the phylum Fusobacteria. The antibiotic combination only reduced the phylotypes EU563242 and EU563262. Based on our results, we conclude that the reduced effect of florfenicol on intestinal microbiota was stronger than that of flavomycin, and when flavomycin and florfenicol were added in combination, the effect of florfenicol overshadowed that of flavomycin.
authors.affiliation: Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, 100081 Beijing, People's Republic of China.
authors.forename: Suxu
authors.initials: S
authors.lastname: He
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Yuchun
authors.initials: Y
authors.lastname: Liu
authors.forename: Yanan
authors.initials: Y
authors.lastname: Cao
authors.forename: Kun
authors.initials: K
authors.lastname: Meng
authors.forename: Pengjun
authors.initials: P
authors.lastname: Shi
authors.forename: Bin
authors.initials: B
authors.lastname: Yao
authors.forename: Einar
authors.initials: E
authors.lastname: Ringø
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000145:classification / Q000235:genetics; D058491:Bacterial Load; D001455:Bambermycins / Q000494:pharmacology*; D002678:Chimera; D023681:Cichlids / Q000254:growth & development*; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004032:Diet; D005260:Female; D007422:Intestines / Q000382:microbiology; D008297:Male; D054892:Metagenome / Q000187:drug effects*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013839:Thiamphenicol / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D001455:Bambermycins; C035534:florfenicol; D013839:Thiamphenicol