Analysis of the rumen bacterial diversity of goats during shift from forage to concentrate diet

GRILLI D; MRAZEK J; KOPECNY J; FLIEGEROVA K; PAEZ LAMA S; CERÓN M; SOSA MA; ARENAS N

Portoroz

Simposio; 9th International Symposium on Anaerobic Microbiology.; 2015

Univ. Ljubljana, Biotechnical faculty, Animal Sci. dept.

Domestic goats (Capra hircus) possess diverse adaptations to harsh environments by having a greater capacity to control the rumen environment. The aim of work was to determine both the abundance and diversity of bacterial community characterizing rumen of goats for which the diet was abruptly shifted from alfalfa hay (AH) to alfalfa hay and corn (AH/C). Eight animals were fed on alfalfa hay (AH) diet for a period of 30 days, then four goats were randomly selected and were abruptly shifted to a mixed forage - concentrate diet consisting of 60% alfalfa hay and 40% corn grain (AH/C diet). The rumen fluid samples were regularly collected five hours after feeding. Total bacterial DNA was isolated by bead-beating approach combined with the column filtration steps of the QIAamp DNA Stool Mini Kit. Bacterial diversities were than estimated by PCRDGGE, quantitative PCR and by high throughput sequencing on Ion Torrent PGM platform with data analysis by QIIME software package.Conclusions:? Switching the diet from hay to hay/concentrate significantly loweredrumen pH, but not bellow acidosis level.? Both PCR-DGGE and NGS methods showed changes in bacterialcomposition.? Changing the diet to concentrate caused increase of ruminococcaceaeand uncultured prevotellaceae and bacteroidales numbers anddecrease of butyrivibrio, lachnospiraceae and genus prevotella.? The ratio of the phyla Firmicutes/Bacteroidetes was higher in hay-fedanimals than in grain-fed animals.? These findings confirm that goats has a great capacity to control thepH of the rumen and thereby maintain a bacterial structure ensuringnormal rumen function.? The methodology used adds a new dimension to the communityanalysis, as it allows quantifying the change in ruminal bacteria andhelps identify how important the change in bacterial structure is forthe ruminal function.