Introduction
Sand has long been considered the “gold standard” of dairy cow bedding because it does not support bacteria growth, resists moisture and provides a comfortable place for the cow to rest.
But assuming the use of 50 pounds of sand per cow per day, sand can become a costly bedding option if a sand recovery system is not in place. Here are three ways you can maximize your sand bedding and keep more cash in your pocket.
1. Begin with a quality washed concrete sand
Success with sand bedding begins with the use of the proper sand. When a sand separation system is incorporated into the manure system, sand selection becomes even more critical.
Research has shown that fine sand tends to pack hard in the stalls, reducing drainage and decreasing cow comfort. Sand that is too coarse will promote drainage but can lead to hoof problems once mixed with the manure in the stalls.
The best way to maximize cow comfort while at the same time maximizing chances for successful sand separation is to use a quality washed concrete sand that falls within the specs for ASTM C-33 sand. If unsure about the quality of sand that is available to you, there are many companies that can perform a sand analysis. McLanahan has a test lab at their Hollidaysburg, Pa., location and can perform the sieve analysis.
The graph below shows the range of particle size distributions in which a washed concrete sand is available. If the sand analysis shows the sand gradation falling to the left of the grey shaded area, the sand is considered “fine” and will have poor separation along with the stall problems mentioned previously.
If the sand gradation lies to the right of the shaded area, the sand would be considered too large. While it would have great separation, cow comfort in the stall and in the alleys would suffer.
Any sand gradation that falls within the shaded area would be considered acceptable for bedding sand.
2. Install a sand separation system
Unfortunately, sand doesn’t just stay in the stalls. As cows use the sand-bedded freestalls, they inadvertently drag manure and other contaminants into the stalls with them and drag the bedding sand out.
Stalls need to be clean, so they are raked and groomed daily to remove manure and contaminated bedding. This ends up being, at minimum, about 50 pounds of sand used per cow per day. This number can be much higher in some cases, especially if dry sand is being used.
The chart below shows what a dairy could spend on bedding sand if they used a minimum of 50 pounds of sand per cow per day without a sand recycling system in place.
If we choose a mid-range cost of $15/ton delivered for sand, a 1,000 cow herd using 50 pounds per cow per day would cost the dairy $136,875 annually for sand bedding. Installing a sand recycling system can help minimize this cost.
Fortunately, there are several different systems to choose from when deciding what system is best for your dairy.
- Mechanical Sand Separation System - Mechanical separation systems are highly versatile systems and can be used with any type of manure system. They achieve high recovery rates of clean sand. These systems are scalable, and can be set up to process manure from well over 10,000 cows on a single site. In cold climates, installing the system in a heated building will allow it to operate all year long.
- Sand Lanes - Sand lanes are an effective means for settling sand but are much less versatile than a mechanical system. They are most effective when high volumes of water are used to clean the alleys and/or transport the manure to a processing location. They are capable of high recovery rates and when coupled with a Sand Lane System, they can ultimately produce a clean, dewatered sand product.
3. Don't neglect regular maintenance
Each of the systems mentioned above require regular, ongoing maintenance for them to remain effective. Sand is an abrasive media, and it manages to find its way into every piece of the system.
McLanahan Separation Systems have been specially designed to provide a long service life under abrasive conditions. Despite this, there are items that will require replacement at acceptable and predictable intervals. Failure to maintain components in the system will cause it to operate ineffectively.
Regular maintenance of this system should include:
- Moving sand and solids piles.
- Visually inspecting all the equipment prior to starting the system or at the beginning of each shift.
- Lubricating machines per equipment schedule.
- Replacing wear items and equipment as necessary.
A sand lane is no exception to this rule either. It will begin to lose its effectiveness if the sand isn’t removed on a regular basis. The high volumes of flush water used in a sand lane are supplied with flush pumps. As these pumps begin to wear, their flow begins to decline, which can lead to poorly cleaned alleys and plugged flume lines.
Regular maintenance of this system should include:
- Removing sand from lanes daily (at minimum).
- Conditioning sand as necessary (if no Sand Lane System is used).
- Lubricating equipment per its schedule.
- Replacing wear items and equipment as necessary (primarily pumps).
Sand continues to provide the most comfortable resting place for your cows. Using it comes with some challenges, but these can be overcome with proper sand selection and a well-designed sand separation system that is properly managed and maintained. For more tips on managing sand bedding, check out this webinar.
