Neglecting these in dairy rations can have lasting impacts on cow health.
By Dr. Elliot Block, Research Fellow, Arm & Hammer Animal Nutrition
The inclusion of buffers in dairy rations is a well-researched and successful strategy. But, buffers seem to have become a forgotten tool—or at the very least, one that’s taken for granted. Neglecting this important part of dairy nutrition can have lasting impacts on cow health and ration.
For example, the owners of a 1,000-cow dairy were concerned their herd was not meeting its productivity potential. Milk production hovered at 26,500 pounds, but milk fat levels seldom rose above 3.4%, or 901 pounds, and dry matter intake (DMI) was somewhat inconsistent, both on an individual basis and across pens. Stocking rate varied, but pens at 115% of capacity were not uncommon.
Furthermore, cows seem to be plagued by various digestive and efficiency concerns—like inconsistent manure scores, signs of indigestion and subclinical acidosis, and a less-than-desirable feed conversion rate.
Looking for answers
A look at the herd’s health records indicated a significant number of off-feed incidents, low rumination rates and cud-chewing activity and poor locomotion scores—along with other hoof health challenges.
A look at the ration also indicated that something wasn’t quite right.
The corn silage-based diet contained an adequate starch-to-fiber ratio and micro and macro minerals were included at recommended levels. However, buffer inclusion rates were minimal—the diet contained only 0.25 pounds of buffer per cow per day and had drifted downward over time. Consequently, it took a while for the effects of this action to appear.
Research1 as far back as 1965 shows that buffers positively impact cow health and performance. And the recommended inclusion rate for sodium bicarbonate, for example, is 0.75% to 1.0% of TMR dry matter.2
The research on buffers over the years has been conducted with diets that were about 50/50 corn silage and haylage. This consideration carries increasing weight since dairies feed cows differently than in the past. Today’s diets include more fermentable carbohydrates—which require more buffering, not less. Rations also minimize fiber (physically effective NDF) and rely more on microbial protein and fermentation than in the past. In addition, variation in feed ingredient quality plays a significant role in ration performance.
Also, overcrowded facilities force cows to gorge rather than eat small meals, which contributes to rumen acidosis.
Given the recommended inclusion rates, a cow eating 60 pounds of DM per day should receive at least 0.5 pounds of buffer per day.
The dairy increased the amount of ration buffer to this level and within months experienced fewer health incidents, improved rumination time, lowered laminitis incidence by 10 percentage points and milk fat production consistently rose 0.2%.
Keep in mind the purpose of buffers is to smooth out the bouts of acidosis that cows will (not "may") experience from time to time.
Dairy producers will probably see more consistent dry matter intake and solids corrected milk and/or energy corrected milk production brought about by a better and healthier rumen environment. However, it will likely not be an immediate and dramatic response, but rather an improvement that can be measured over the course of a month or two.
1 Miller RW, Hemken RW, Waldo DR, Okamoto M, Moore LA. Effect of Feeding Buffers to Dairy Cows Fed a High-Concentrate, Low-Roughage Ration. J Dairy Sci. 48:1455-1458. 1965.
2 Shaver RD. Feed Delivery and Bunk Management Aspects of Laminitis in Dairy Herds Fed Total Mixed Rations. University of Wisconsin – Madison. Available at: http://www.uwex.edu/ces/ag/teams/dairy/italy001.pdf. Accessed March 3, 2014.