Dairy operations are a major source of ammonia emissions. Studies have shown that bedding material can influence the magnitude of ammonia emissions.
In a laboratory setting, researchers at the U.S. Dairy Forage Research Center in Madison, Wis., analyzed the characteristics of six bedding materials — chopped wheat straw, sand, pine shavings, chopped newspaper, chopped corn stalks and recycled manure solids — and their effect on ammonia emissions from dairy cattle urine. Here are some of the results, as reported in the December 2005 Journal of Dairy Science:
Recycled manure solids were the most absorbent bedding material. Sand was the least absorbent.
When urine was applied to dry bedding, ammonia emissions over 48 hours were lowest for sand, followed by pine shavings.
Ammonia emissions increased linearly with absorbance capacity, and decreased as the density of the bedding materials increased.