Diurnal Variation Patterns in the Rumen of Cattle: Studies of Bacterial Numbers, Carbohydrate-Specific Groups and Ruminal Fluid Parameters

Diurnal variation in the size and composition of mixed rumen bacterial populations in cattle fed either high forage or high concentrate diets (maintenance intake levels) was followed after a once daily feeding. Samples of ruminal contents were collected from rumen-fistulated, Holstein steers at -1, +2, 4, 8, 12 and 16 h after feeding. The bacterial population of each was separated from feed particles, protozoa and ruminal fluid by differential centrifugation. The population was then assessed for total and viable cell counts and bacterial cell constituents. After the viable bacterial count was determined, the colonies were replica plated onto an array of differential media. These media were previously shown to separate the rumen bacterial population into groups on the basis of carbohydrate substrate utilization specificities. Colonies which developed on these media represented the major carbohydrate metabolizing groups comprising the bacterial population at the time of sampling. Fermentation acids, carbohydrate and ammonia levels were also determined in the corresponding ruminal fluid samples and the pH levels were measured.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Dairy Science

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Leedle, Jane Alice Zeigler

• Agriculture, Animal Culture and Nutrition

Identifier

(UMI)AAI8203515

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/71715