|SMITH, K - New Mexico State University|
|GARZA, A - New Mexico State University|
|BUTTERFIELD, K - New Mexico State University|
|Wells, James - Jim|
|LODGE-IVEY, S - New Mexico State University|
Submitted to: Translational Animal Science
Publication Type: Proceedings
Publication Acceptance Date: 4/14/2018
Publication Date: 9/1/2018
Citation: Smith, K.E., Garza, A.L., Butterfield, K.M., Dickey, A.M., Lindholm-Perry, A.K., Wells, J. E., Freetly, H.C., Lodge-Ivey, S.L. 2018. Succession of ruminal bacterial species and fermentation characteristics in preweaned Brangus calves. Translational Animal Science. 2(Supplement 1):S48-S52. https://doi.org/10.1093/tas/txy043.
Technical Abstract: Historically, rumen development has been defined by anatomical change, fermentation end products, and cultured media for identification of bacterial composition (Tamate et al., 1962; Fonty et al., 1987). The rumen ecosystem from 1 d to 2 yr of age declines in aerobic and facultative anaerobic taxa, while increasing anaerobic taxa (Jami et al., 2013). Li et al (2012) reported Bacteroidetes as the prominent phylum in 42-d-old calves, different from 14-d-old calves. This research has focused on dairy calves, which wean earlier, live in different environments, and likely has a different rumen developmental timeline in comparison to beef calves. The energetic efficiency of a cow converting grass to milk and the calf converting milk to retained energy is less efficient than directly converting forage to retained energy (Freetly et al., 2006). Intake of solid food increases ruminal microbial activity and higher concentration of total VFAs produced that can be utilized for retained energy (Coverdale et al., can be utilized for retained energy (Coverdale et al., 2004). Butyrate is especially important in rumen development and has been linked to papillae development in the rumen (Coverdale et al., 2004). Ruminal ammonia is vital for adequate microbial growth, therefore important for microbial and fermentation development (Satter and Slyter, 1974). Thus, the objectives of this study are to assess the composition of the ruminal bacteria and the production of fermentation end products in preweaned Brangus calves as they age. We hypothesize that ruminal VFA, ammonia, and bacterial populations will increase as calves age.