Bos taurus rumen metagenome Metagenome
Solid feed intake of carbohydrates from cereal grains initiates rumen development, by stimulating rumen microbial proliferation and volatile fatty acid (SCFA) production. To date hybrid rye has been hardly used in calf starter diets and questions remain as to how hybrid rye in calf diets affects ruminal fermentation, microbiota composition and the risk for the development of rumen acidosis in calves. Furthermore, there is a lack of scientific research on evaluating how much wheat can be replaced by hybrid rye in calf starter feed. In this study, we evaluated the effects of inclusion level and physical form of hybrid rye as replacement for wheat in total mixed rations (TMR) for weaned calves on the bacterial community and fermentation efficiency in vitro using the rumen simulation technique (RUSITEC). Fermenter fluid was collected at 4, 8, and 24 hours of incubation of rumen fluid with 5 different total mixed rations with 0, 25 or 46% hybrid rye either in ground or rolled form on day 8 of the experiment. The DNA was isolated using a commercial kit and sequenced using Illumina chemistry. The V3-V4 hypervariable regions of bacterial 16S rRNA gene were amplified using a 250 bp read length paired-end protocol (Novogene) on an Illumina Novaseq 6000 platform, including the library preparation (NEBNext Ultra II DNA Library Prep Kit) and sequencing.