Our findings agree with the hypothesis that the diet-induced obesity is related to changes in the relative abundance of Firmicutes and Bacteroidetes and especially an increase in proportion of the bacteria belonging to the phyla Firmicutes. We also point to HF/high-caloric diet as a contributing factor that changes the gut microbial community. To our knowledge this is the first study that has investigated the effects of diet-induced obesity on gut-microbiota in cloned pigs. More investigation is needed to optimize the cloning of experimental animals which could eventually offer a more controlled experimental model. Acknowledgements

CDK inhibitor This work was supported by a grant from the Danish Strategic Research Council (FØSU 2101-06-0034), and The Danish Research Council FTP (09–6649307). We would like to thank Sophia Rasmussen and Joanna Amenuvor for excellent technical assistance. Electronic supplementary material Additional file 1: An overview of T-RFs (bp) in cloned and non-cloned pigs and

possible bacterial taxonomy as estimated in silico through the MICA online database. (DOCX 14 KB) Additional file 2: GS-7977 molecular weight correlation between weight gain and relative abundance of Bacteroidetes Fosbretabulin clinical trial and Firmicutes. Correlation between weight-gain and relative abundance of Bacteroidetes as calculated by Spearman correlation in cloned pigs (r= −0.33, P<0.04) and non-cloned control pigs and

correlation between weight-gain and relative abundance of Firmicutes in cloned pigs (r= 0.37, P<0.02) and non-cloned control pigs (r=0.45, P<0.006). Each color represents a pig in that group i.e. pig 1 is indicated by a red dot and so on. (PDF 15 KB) References 1. Stewart JA, Chadwick VS, Murray A: Investigations into the influence of host genetics on the predominant eubacteria in the faecal microflora of children. J Carbachol Med Microbiol 2005, 54:1239–1242.PubMedCrossRef 2. Zoetendal EG, Akkermans AD, WM K-v V, de Visser JA, de Vos WM: The host genotype affects the bacterial community in the human gastronintestinal tract. Microb Ecol Health Dis 2001, 13:129–134.CrossRef 3. Turnbaugh PJ, Hamady M, Yatsunenko T, Cantarel BL, Duncan A, Ley RE: A core gut microbiome in obese and lean twins. Nature 2009, 457:480–484.PubMedCrossRef 4. Murphy EF, Cotter PD, Healy S, Marques TM, O’Sullivan O, Fouhy F: Composition and energy harvesting capacity of the gut microbiota: relationship to diet, obesity and time in mouse models. Gut 2010, 59:1635–1642.PubMedCrossRef 5. Pang X, Hua X, Yang Q, Ding D, Che C, Cui L: Inter-species transplantation of gut microbiota from human to pigs. ISME J 2007, 1:156–162.PubMedCrossRef 6. Guilloteau P, Zabielski R, Hammon HM, Metges CC: Nutritional programming of gastrointestinal tract development. Is the pig a good model for man? Nutr Res Rev 2010, 23:4–22.PubMedCrossRef 7.