Phosphorus Management

 

Supplemental phosphorus sources vary in Phosphorus (P) content and availability. 

 

 

% P

% Availability

% Waste

Phos Acid

31

90

10

Calcium Phosphate

21.6

80

20

Sodium Tripolyphosphate

25

75

25

Dicalcium Phosphate

19.3

75

25

Defluorinated Phosphate

18

65

35

 

 

 

 

Phosphoric acid is the P source used in Westway liquid supplements.  The P in Phosphoric Acid is more concentrated and more available than any other supplemental ingredient.  This means that less supplement is fed and less P is carried out in manure.

 

This chart shows the amount of total P supplement needed to achieve 10 grams P absorbed, and the amount of waste P that must be disposed of.

 

 

 

 

 

 

 

The effect of the proportion of supplemental phosphorus excreted is significant. 

 

In a ration requiring 10 grams of supplemental absorbed Phosphorus, use of Dicalcium Phosphate will produce 260 lbs waste Phosphorus annually.

 

The same amount of absorbed supplemental Phosphorus from Phosphoric Acid will produce only 89 lbs waste Phosphorus/100 cow herd/year. 

 

This information is based on the 2001 National Research Council “Nutrient Requirements of Dairy Cattle”.