Seventy percent of the protein your herd uses for lactation is derived from the microbial population in her rumen. Researchers from UC Davis and Feedworks USA sought to learn more about how different substrates might impact rumen microbial efficiency. They did this with the ultimate goal of increasing the flow of protein available for absorption to help offset feed costs, recognizing protein is the highest cost of the ration, and likely the largest fraction to the cost of production on most dairies.

“We know that efficency of growth in the rumen varies dramatically, nearly 2 fold. Microbes can use 1/3 of their energy for growth or as much as 2/3,” Hackmann described. His lab is using invitro cultures to attempt to determine why this variation exists. “If we can pinpoint cause then we can accomidate and make microbes grow more efficiently and deliver more protein to the ruminant at a lower cost.”

Past models, used in ration formulation software such as CNCPS, claim rumen bacteria perform digestion more efficiently when fed cellulose, over glucose. However, featured work by Dr. Tim Hackmann’s invitro lab suggests a different result. “We found there will be a larger mass of microbes that grow on glucose then cellulose but they also digest more, so the efficiency is not differnet.”

Listen-in to this episode for in interesting dive into the expected changes in the rumen under these conditions. An added bonus banter from Dr. Benjamin Wenner, ruminant nutritionist with FeedWorks USA and co-author on the featured article, about the futuristic concepts possible for ruminant nutrition with mindful investment.

Topics of discussion

1:29      Introduction of Dr. Tim Hackman and Dr. Benjamin Wenner

Mixed rumen bacteria grow with similar efficiency on cellulose and glucose