THE PHYSICAL FORM OF CORN INFLUENCES THE RUMEN BACTERIAL BIODIVERSITY – PRELIMINARY RESULTS

Abstract

The aim of this study was to investigate the rumen bacteria in terms of genetic biodiversity and variation due to different physical form of corn in cow diet. A total of twenty dry cows were fed for 3 months with the same diet, only differed for corn physical form, ten received corn grains, while the other ones received corn flour. To investigate the biodiversity of the bacterial 16S rRNA gene clone library analysis has been conducted and then the sequencing has been carried out using Ion Torrent PGM™ System. Bacterial population was tested using R statistical software. The Kruskal-Wallis one-way analysis of variance (Kruskal-Wallis, 1952) confirmed that the bacterial populations were different when the animals were fed grain compared with flour corn. Both the OUT’s abundance (Operational Taxonomic Unit) and the biodiversity indexes presented a significant difference among the two sample groups, underlining the large changes that take place even with small diet modifications in ruminal environment. There is still the need to deepen how exactly the diet changes the rumen phylogenetic structure and the consequences on bacteria’s activity.

Keywords

• rumen bacterial biodiversity
• diet composition
• physical form
• OTUs