2026-09-21T14:19:48Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/49547 2023-07-11 col_2142_5131 col_2142_14771 com_2142_5130 com_2142_685 com_2142_397

Loor, Juan J. Alqarni, Saleh 2014-05-30T16:49:23Z 2014-05-30T16:49:23Z 2014-05 2014-05-30T16:49:23Z 2014-05 Seven rumen cannulated Holstein cows were used from 3 weeks prepartum to 4 weeks postpartum to determine the relative abundance of 7 different species of ruminal microorganisms. The prepartum diet was based on corn silage. In the postpartum, diet included ground corn, grain by-products, and alfalfa haylage. Ruminal digesta were collected at five times: -14, -7, 10, 20, and 28 days around parturition. Total DNA from ruminal digesta was isolated and real-time quantitative PCR was used to determine the relative abundance of bacterial species. Eubacterium ruminantium and Selenomonas ruminantium were not affected by time (P>0.05). Megasphaera elsdenii and Prevotella bryantii increased significantly postpartum (P<0.001). Conversely, Butyrivibrio proteoclasticus decreased gradually from -14 through 28 days (P<0.001). Fibrobacter succinogenes was affected by time being lowest at day 10 (P=0.02) while Anaerovibrio lipolytica recorded the lowest abundance at -7 d followed by an increase by 20 days postpartum (P<0.001). Overall, these results indicate that changes in diet after parturition affect the abundance of ruminal bacteria, particularly M. elsdenii (a lactate-utilizing bacteria) and P. bryantii (a starch-degrading bacteria) which increased markedly after parturition likely as a consequence of a higher concentrate intake. In terms of milk production, there was a relative decrease in the body weight of dairy cows.The milk yield increased considerably up to the fourth week, while the percentage of fat was reduced considerably. Item withdrawn by Laura Spradlin (lspradl2@illinois.edu) on 2014-05-02T20:28:53Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 2 Alqarni_Saleh.docx: 138220 bytes, checksum: 59d95b1d60f522dfd023355c3bcb12ed (MD5) Alqarni_Saleh.pdf: 1733456 bytes, checksum: af56fed1a8a0e7460d0f10b5c3a0341f (MD5) Made available in DSpace on 2014-05-30T16:49:23Z (GMT). No. of bitstreams: 4 Saleh_Alqarni.pdf: 1727425 bytes, checksum: 4fc5b514a0d6f9d8e4dbd132c040088a (MD5) Alqarni_Saleh.docx: 150028 bytes, checksum: e7323b98bc84d8c30d359e96ef5e2585 (MD5) 1_Alqarni_Saleh.docx: 150028 bytes, checksum: e7323b98bc84d8c30d359e96ef5e2585 (MD5) license.txt: 4063 bytes, checksum: e292bea8402517cb721fb0c08de91cc5 (MD5) http://hdl.handle.net/2142/49547 en Copyright 2014 Saleh Alqarni Rumen bacteria Transition cows Rumen metabolism The rumen microbial ecosystem during the transition period in dairy cows text Animal Sciences 1538 Animal Sciences 0002 University of Illinois at Urbana-Champaign Thesis M.S. MS:Animal Sciences -UIUC 10KS0002MS