The benefits of sand bedding for dairy cows are many. However, sand is not always the easiest material to incorporate into manure management systems.
Bedding with sand impacts every aspect of your dairy farm, from the cows you milk to the crops in your fields. The following recommendations can help you reap the benefits of sand while keeping sand in its place with the right manure system management skills and equipment.
Cow comfort
Generally speaking, the more time cows spend lying down, the more milk they make. Clean, dry, deep sand-bedded stalls are more comfortable for cows, which leads to longer lying time.
Research shows stall surface can influence lying time, with sand being a preferred option for cows. Herds with deep-bedded stalls also have a significantly lower prevalence of lameness compared to herds with mattress stalls.1
Because sand is inorganic, mastitis-causing bacteria struggle to thrive within it. As a result, properly maintained sand-bedded stalls can benefit milk quality and cow health.
With all the benefits sand bedding provides, it makes sense why it is often the preferred choice for many dairies. The key is to keep sand working for cows where it does the most good, and away from where it does not.
Moving and separating
Because it’s heavier than manure, sand eventually settles out of manure streams since it cannot remain in suspension indefinitely. For this reason, it is best to store sand and manure solids separately whenever possible.
This principle is also a good reason to incorporate sand separation in your manure management system.
With the right sand and a properly designed and managed sand separation system, most farms achieve more than 90% sand recovery rates. These solutions allow you to repeatedly reuse sand bedding, saving purchase costs.
Sand-laden manure is also abrasive to equipment, but heavy-duty equipment specifically engineered for on-farm conditions will help to corral sand and extend the life of manure system components, reduce downtime and lower maintenance costs.
Anaerobic digesters
The impact of sand increases in importance as more dairies turn to anaerobic digester technology.
Without separation beforehand, sand-laden manure is largely incompatible with anaerobic digester systems. Keep in mind, it may take several steps to remove the maximum amount of sand from manure before digestion, including mechanical sand separation, a hydrocyclone and a sand lane or other tools.
Work with your manure management partners to ensure you are properly equipped to meet the standards needed for successful digester function.
Field effects
Every soil is unique. Therfore, the precise effects of land application of sand-laden manure vary based on location and original soil texture. However, sand has been shown to influence several important soil characteristics following repeated application.
The effects of this application are slow but accumulate over time. Research shows that over many years, applying sand-laden manure can change the composition of soils.2
Using the recommended 50 pounds of sand per stall per day multiplied by 365 days in a year equates to 18,250 pounds of sand per stall per year or about 2/3 of a dump truck per year per cow stall.
Many dairies have a land base of two to five acres per cow. At that rate, if equally spread, a farm will add between 4,550 pounds and 9,125 pounds of sand per acre per year. Depending on tillage, application levels, soil type and other factors, in 25 to 50 years, the soil sand percentage may increase by 20%.2
Perhaps more important is that repeated sand applications to fields change soil texture and lower its ability to easily absorb water. This reduction potentially leads to increased field runoff, taking with it valuable water and nutrients.
Removing sand prior to field application of manure will help dairies, and their crops, gain more benefit from this organic fertilizer.
An asset that requires management
Manage sand as the valuable asset it is for your dairies. You and your cows benefit from sand remaining in the places on your farm where it provides the most advantage – under cows and not in storage facilities, anaerobic digesters or fields.
Success begins and ends with capitalizing on physics, good partnerships and engineering know-how.
1 Pineiro J, Spencer JA. 2020. Lying Time of Dairy Cows: Importance of a behavioral need. Texas A&M University. Available at: https://texasdairymatters.tamu.edu/files/2022/01/Lying-Time-of-Dairy-Cows.-Importance-of-a-behavioral-need.pdf.
2 Livestock and Poultry Environmental Learning Community. 2019. Sand bedding for cows, is it a contaminant? Is it sustainable for our soils? Available at: https://lpelc.org/sand-bedding-for-cows-is-it-a-contaminant-is-it-sustainable-for-our-soils/
