Submitted to: Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: May 21, 2008
Publication Date: August 22, 2008
Citation: Ziemer, C.J., Weber, T.E., Kerr, B.J. 2008. Affect of corn germ meal inclusion in pig diets bacterial ecology in the cecum and proximal colon [abstract]. 12th International Symposium on Microbial Ecology, August 17-22, 2008. Cairns, Australia. 2008 CDROM. Technical Abstract: Inclusion of bio-fuel co-products in swine diets is becoming more common due to greater availability and increasing cereal grain costs. These co-products have lower starch and higher fiber concentrations. Twenty-four pigs were adapted to diets with either corn or solvent extracted corn germ meal (CGM). Corn germ meal feeding began in weaning diets at 7.5% and was increased, in phases, to 40% in finishing diets; total feeding period was 16 weeks. Dietary hemicellulose in finishing diets was 6.2% in corn and 18.3% in CGM diets. After 16 weeks, samples were obtained from the cecum and proximal colon for bacterial community analysis. Initial analysis used denaturing gradient gel electrophoresis (DGGE) targeting the V3 region of the16S rRNA gene to examine bacterial community dynamics. In the cecum, the average number of DGGE bands differed (P = 0.07) between corn (19 bands) and CGM (15 bands) diets; however, band numbers did not differ in the proximal colon averaging 12 bands. Band numbers in cecal samples were significantly greater (P=0.001) than in proximal colon samples on both diets. Very few bands aligned in both the cecum and proximal colon within an animal (0/4, 1/9, 2/5, and 3/5; matched bands/number of animals). Overall, banding patterns in the proximal colon were more similar than in the cecum. There was a greater tendency for proximal colon samples to cluster by dietary treatment than for cecal samples. Increased dietary fiber in pig diets tended to decrease bacterial diversity, perhaps due to the need for more specialization.