Path to Profitability with Precise Dairy Nutrition

Nowadays, precise nutrition is as relevant to milk production as precision agriculture and GPS technology are to yield in field crops. But what is precise dairy nutrition, exactly?

Feeding dairy cows an optimal diet requires an understanding of the needsof animals capable of producing large quantities of milk and milk components, and using the farm's resources as effectively as possible. The Newton® nutrition model is regularly updated with data from the latest research to balance feed rations as precisely as possible.

Sampling: a crucial step

Precision nutrition starts from the moment forage samples are taken on the farm. Given that forages make up 50-65% of dairy cow rations, variations have a major impact on productivity. To specify the nutrient intake, it is important to start with a rigorous sampling procedure.

What varies the most in forages?

A study conducted in Vermont demonstrated that the daily variation is responsible for 48% of the total variation in dry matter (DM) in corn silage and 64% in hay silage (see Figure 1, columns 1 and 2). If you think back to those beautiful harvest days, the dry matter in your silage varied considerably between your first trip to the silo and your last. This would explain why dry matter varies in the silo.

Thirty percent (30%) of the remaining variation can be attributed to the sampling procedure, which is why sampling methods should be standardized and applied methodically.

Significant variation in potential digestibility

Tests conducted by Shur-Gain over a five-week period demonstrated the same phenomenon. Figure 2 shows the variation in potential digestibility (PD) noted on two dairy farms over a three-week period. During this period, the corn silage on Farm 1 had an average PD of 79.3%. However, the PD varied from 75.2% at the lowest level to 81.9% at the highest level, a deviation of 6.7%. The corn silage on Farm 2 had an average PD of 74%, varying from 72.4% to 75.4%, a deviation of 3.0%. Farm 1 had silage of higher quality, but its results varied significantly more than those on Farm 2. The purpose of this study was to understand if this variation was due to the silage itself or due to the sampling technique, as noted by Normand St-Pierre and Bill Weiss (1) in an article presented at the Western Dairy Management Conference in Reno, Nevada, in March 2015.

Better sampling for more precise nutrition

It is not sampling frequency, but sampling quality that will ensure the greatest precision. Our study led us to conduct a literature review on the subject, as well as a statistical analysis of several sampling techniques used in different storage types (horizontal silos, tower silos, round and square hay bales). Standard operating procedures (SOP) were developed to help producers take better forage samples.

Adjusting rations to variations in dry matter right on the farm

Variations in dry matter from one day to the next can impact your farm's performance, whether in terms of milk production or increased costs.

Ration tests conducted with Newton® quantified the effects of such variation. Table 1 shows the effect of the variation in dry matter (DM) in third-cut hay silage, which varied from 40.6% to 34% dry matter. The quantity of hay silage is 17.8 kg when DM is at 40.6%. However, if the forage's DM drops to 34%, the cows will be lacking in total mixed rations (TMR) at the end of the day unless the proper DM adjustment is made.


If you decide to adjust for two more cows at the next feeding, this will increase the quantity of all the ingredients used (see the third column in the table) and therefore increase feed costs by $0.27 per cow per day and raise the percentage of concentrates from 35% to 36.6%.

Checking the dry matter in your silage two to three times a week using a Koster moisture tester can help you make a better-informed decision. In our example, given that the silage was wetter, you could have simply given 21.2 kg per cow instead of the initial 17.8 kg to get an equivalent ration.

For greater productivity and profitability, avoid variations by regularly testing the dry matter on your farm according to variation-reduction methods.

Ask your Shur-Gain dairy nutrition advisor about which procedures would be best for your farm. Since forages make up a large part of the ration fed to ruminants, reducing variation will help improve your productivity and profitability.