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 effectiveness as evidenced by the following case study.
The owners of a 1,000-cow dairy were concerned their herd was not meeting its productivity potential. Milk production hovered at 26,500 lbs., but milk fat levels seldom rose above 3.4%, or 901 lbs., 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, the 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.
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 offered further evidence that something was amiss.
The corn silage-based diet contained an adequate starchto-fiber ratio and micro and macro minerals were included at recommended levels. However, buffer inclusion rates were minimal – the diet contained only 0.25 lbs. 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 lbs. of DM per day should receive at least 0.5 lbs. of buffer per day.