Providing Phosphorus in Different Ways

The cost of phosphorus, a key component in dairy cow rations, is climbing, due to high demand. Phosphorus is a major component of mineral supplements included in livestock rations, as well as a key component in fertilizers used for crop production, and those two industries are responsible for a large part of the phosphates used across the world.

However, crops and livestock don’t represent the only industries demanding phosphorus. Industrial production of paints, detergents and textiles is also driving demand for phosphorus, which can cause fluctuation in pricing for livestock producers.

Phosphorus is especially important for dairy cows, as it is the second most abundant mineral present in cows, after calcium, and the third most abundant mineral in milk (calcium being No. 1, and potassium No. 2). Unlike potassium and calcium, phosphorus is expensive, and the rising costs have a noticeable impact on the costs of mineral mixes and supplements for the livestock industry.

Lactating dairy cows require about 0.45–0.50 percent phosphorus in their diets to maintain milk production. Milk contains about 0.5 gram of phosphorus per pound, which means that high-producing cows are putting out a considerable amount of phosphorus in milk.

One place where we can look for phosphorus to offset the rising cost of mineral supplements is in other feed ingredients making up the protein and forage portion of dairy cow rations. As the table below shows, canola meal can help meet phosphorus requirements easier than most ration ingredients. The National Research Council’s “Nutrient Requirements of Dairy Cattle” lists solvent-extracted canola meal as having a very high amount of phosphorus at 1.1 percent of dry matter. Also very important is the fact that recent studies have found that the phosphorus found in canola meal is highly available to ruminant animals.

Phosphorus Content of Some Common Feed Ingredients*

Ingredient Phosphorus, % of DM
Canola meal, solvent extracted 1.10
Alfalfa meal 0.28
Corn grain 0.30
Cottonseed meal 0.60
Linseed meal, solvent extracted 0.83
Corn distillers’ grains 0.83%
Sorghum grain 0.35
Soybean meal 0.71


*From NRC Nutrient Requirements of Dairy Cattle, 2001


With rising input costs, producers must find ways to maximize the dollars they do spend. So, if you’re looking to find an alternative source of phosphorus outside your mineral supplements, consider looking to canola meal.