Updates to a dairy nutrition model developed at Cornell University may help farmers improve their economic margin and reduce the amount of nitrogen pollution in the environment.
The Cornell Net Carbohydrate and Protein System (CNCPS) is a model that helps farmers determine what to feed dairy cows to make milk production more efficient and environmentally friendly.
On-farm research in Broome, Tioga and Delaware counties in New York revealed that farmers can feed cows less protein, maintain a cow’s milk-production output and reduce nitrogen in the manure. This means the nutrient does not run off into waterways and lakes, which can promote unwanted algae.
The researchers used the CNCPS to formulate diets in eight herds of cows in New York, and found that it could reduce nitrogen in manure by about 14%.
On one 50-cow farm, the researchers found the amount of protein in the feed dropped from 16.3% to 14.9%. In the farm’s manure output, there were 1607 fewer pounds of nitrogen put into the environment annually with no change in milk production. On a 565-cow farm, the protein feed input dropped 1%, which resulted in nearly 80 g less nitrogen in cow’s manure daily and reduced nitrogen excretion by 18.6%. That translates into 35,916 fewer pounds of nitrogen in the environment annually.
The researchers noted that reducing the protein portion of the feed to enhance efficiency also saves farmers money. Using 2017 feed prices as a base, they stated a farmer can save between $147 and $157 per cow annually.
«I call it a win-win. The dairy farmers win because the cow is more efficient and more profitable. Society wins because we’re now putting fewer nutrients back into the environment or into the water than we would have had we not made the adjustments,» said Larry Chase, Professor Emeritus of Animal Science.
The researchers concluded: «The CNCPS can be used to assess the environmental impact of dairy cattle and by nutritionists to improve the utilization efficiency of diets and cattle in the environmental context.»
The research was published in the journal Applied Animal Science.
This is an edited version of an article originally published on the Cornell Chronicle.