Several factors related to feeding cattle, including phosphorus nutrition, will be affected by the mandated increase in ethanol production, says Bill Weiss, dairy extension specialist at The Ohio State University. 

“Byproducts such as distillers grains, corn gluten feed, and wheat middlings are often less expensive sources of nutrients than other feed ingredients, but these ingredients also have high concentrations of phosphorus,” Weiss says. 

Weiss points to recent research from Virginia Tech that shows high phosphorus diets were cheaper than low phosphorus diets. 

“With the ingredient prices used in that study, feed costs were about $0.20/cow/day less for a diet with 0.45% phosphorus than for one with 0.35% phosphorus, but only if dietary phosphorus increased because of the use of byproducts, not by adding supplemental phosphorus,” Weiss says. 

"Feeding a diet with 0.45 vs. 0.35% phosphorus is cheaper, but it would increase manure excretion of phosphorus by about 25 grams/cow/day (about 5.5 lb/day for each 100 cows). If this extra phosphorus in the manure can be used efficiently by crops without contaminating water or causing excessive phosphorus build up in the soil, then higher phosphorus diets are economically and environmentally sustainable," Weiss says. 

However, if manure phosphorus cannot be used efficiently and correctly, consider the options available for reducing manure phosphorus.

Click here for more details on the options available to you.

Source: Buckeye Dairy News, March 2012