The information below has been supplied by dairy marketers and other industry organizations. It has not been edited, verified or endorsed by Hoard’s Dairyman.

Often, rations can change seasonally. In fact, it’s common for producers to experience lower butterfat tests and higher numbers of butterfat inversions this time of year.1

These fluctuations are often due to variable starch digestibility of corn silage or high-moisture shell corn (HMSC). Changes in the ration are needed to account for this variability — otherwise, herds are at risk for Sub Acute Ruminal Acidosis (SARA).

“Especially this time of year — but really no matter what the season — SARA is an important problem for producers to be on guard against,” says Tony Hall, MSc MSB, PAS, Technical Services – Ruminant, Lallemand Animal Nutrition. “In addition to reduced milk components, producers can also see lowered feed intake or loose manure.1 These are all common signs that SARA may be affecting a herd.”

A cow is defined as experiencing SARA when her rumen pH is below 5.8 for a combined total of three hours or more over a 24-hour period.1 In this acidotic state, the rumen isn’t optimized to make the best use of any ration. Any operation using corn silage or HMSC should watch for seasonal swings in production, Hall advises.

After six to eight months in storage, the fermentation process continues to break down starch-protein structures in the corn silage or HMSC. Increased amounts of rumen-digestible starch and higher rates of digestibility combine to push cows into SARA. In addition, feeding behaviors and silage stability can change.3,4,5

“All these factors make this season a particularly hard time for dairy producers to keep performance consistent,” Hall notes. “The number one way to fight back against SARA is to monitor critical areas regularly and make appropriate ration changes.”

Hall recommends producers:

  1. Monitor dry matter (DM) content in ensiled forages and moist feedstuffs every week
  2. Test for total starch content, starch digestibility and starch degradation rate on ensiled corn silage and HMSC every month
  3. Monitor the total mixed ration (TMR) for both neutral detergent fiber (NDF) and physically effective-NDF content
  4. Make sure the total oil and polyunsaturated fatty acid content is not excessive
  5. Ensure sufficient salt and buffer content
  6. Confirm the dietary cation-anion difference value is adequately positive
  7. Ensure particle size distribution of the TMR is as expected, and that the ration is dispersed evenly along the feed bunk and regularly pushed up, to help address changes in feeding behavior
  8. Include a rumen-specific active dry yeast (ADY) probiotic in the ration to help maximize rumen function.

One ADY probiotic — Levucell® SC containing Saccharomyces cerevisiae CNCM I-1077 — has been shown to help maximize rumen function in all life stages of dairy cattle. Research shows cows fed an ADY specifically selected to maximize rumen function spend significantly more time above the SARA threshold6 and even produce 2.1 pounds more per day of 3.5% fat-corrected milk (FCM) per cow per day.7

“Helping dairy cattle maintain a more consistent rumen pH can optimize rumen function — avoiding SARA and making the best use of any ration,” Hall says. “No matter what the season, all herds can benefit from better rumen efficiency and greater productivity.”

Lallemand Animal Nutrition is committed to optimizing animal performance and well-being with specific natural microbial product and service solutions. Using sound science, proven results and knowledge, Lallemand Animal Nutrition develops, manufactures and markets high value yeast and bacteria products ─ including probiotics, silage inoculants and yeast derivatives. Lallemand offers a higher level of expertise, leadership and industry commitment with long-term and profitable solutions to move our partners Forward. Lallemand Animal Nutrition is Specific for your success. For more information, please visit www.lallemandanimalnutrition.com.

1 Bramley E, Lean IJ, Fulkerson WJ, Stevenson MA, Rabee AR, Costa ND. The definition of acidosis in dairy herds predominantly on pasture and concentrates. J. Dairy Sci. 2008;91:308-321.

2 Dohme F, DeVries TJ, Beauchemin KA. Repeated Ruminal Acidosis Challenges in Lactating Dairy Cows at High and Low Risk for Developing Acidosis: Ruminal pH. J. Dairy Sci. 2008 (91) 9: 3554-3567.

3 Ferraretto L, Shaver RD, Lauer J. Influence of ensiling on the digestibility of whole plant corn silage. Wisconsin Forage Team - Focus on Forage. 2014;3(16).

4 Huibregtse A, Heuer C, Shaver RD, Hoffman P. Opportunities to improve starch digestibility on dairy farms. University of Wisconsin Extension. 2012.

5 Hoffman PC, Shaver RD. Corn silage, fermentation time, and starch digestibility: What makes it tick? 2011. Available at: http://dl.dairycattlecenter.com/present/%D8%AA%D8%BA%D8%B0%DB%8C%D9%87/Hoffman%20(2).pdf.

6 Bach A, et al. Daily rumen pH pattern of loose-housed dairy cattle as affected by feeding pattern and live yeast supplementation. Animal Feed Science and Technology. 2007;(136):146-153.

7 de Ondarza MB, et al. Case Study: Multiple-study analysis of the effect of live yeast on milk yield, milk component content and yield and feed efficiency. The Professional Animal Scientist. 2010;(26):661-666.