Manure Management: All Important For Today's Dairies

Published on Thu, 01/19/2023 - 12:30pm

Manure Management: All Important For Today's Dairies.

 By Jaclyn Krymowski.

 As far back as the family milk cow, manure management has been an integral part of dairy farming.

While our herds have grown significantly over the years, so has the technology and machinery to manage waste. Today, though, we face new  challenges -  proactively telling our story as environmental stewards, overcoming additional regulations, and, of course, balancing farm needs with the niceties of  “being a good neighbor.”

According to Donald Pfost and Charles Fulhage of the University of Missouri in their bulletin Dairy Manure Management Systems, dairy manure is about 88% water. However, when moisture is reduced to 75% to 85%, it can be considered a solid. This can be accomplished by either decreasing moisture or adding bedding.

You can ease the burden of waste management - and even capitalize on a product that has long been considered a waste - by learning how to better collect, treat, and store manure and keep abreast of changes in handling standards and methods.

Why manure matters
Manure management includes the collection, treatment, and storage of cattle waste. Proper waste management not only ensures food safety but also provides a clean and healthy environment for cows by reducing pathogen exposure and breeding grounds for parasites.

How manure is removed and processed also impacts its second life as a fertilizer. Manure type (liquid, slurry and solids) needs to be considered for it to be effectively applied on a field at the home farm or moved elsewhere.

In recent years, many dairies have installed anaerobic digesters. Not only does this technology cut down on methane emissions and odors, but it also provides a source of power and yields solids that can be used as fertilizer. While digesters provide valuable opportunities, manure collection and handling must be considered to make it a viable option.

Finally, there is the point about the environmental impact and regulations, topics that cannot go unaddressed when discussing manure. Though environmental concerns and regulations vary by region, nearly everyone who plans to expand will need to address how manure is managed.

Collection and storage
The first step in the manure handling process begins by removing it from the barn. While many freestall dairies l depend on bucket scrapers and skid steers to remove manure, the rise in sand bedding and more complex handling equipment has led to a growth in automatic (and robotic) scrapers and flushing systems.  

Flushing into lagoons can also help to reduce CO2 emissions from excessive equipment usage. Though flush systems require additional water, which can be scarce at times, they can be set up to effectively manage this precious resource.

Manure flushing has also been shown to reduce ammonia emissions because it is more effective in removing manure than scrapping or vacuuming, according to the University of California-Davis CLEAR Center.

Typically flushing systems recycle the water used to flush manure by reusing it to flush the alleys or barn again. This limits water waste and is a resourceful way to reuse water.

Handling systems
Traditionally, manure is used as a fertilizer or soil amendment because it is an excellent source of nutrients for plants. It contains high amounts of nitrogen, phosphorus, and potassium.

To properly apply manure to the field, season and weather must be considered. As well, during expansion, farms will need to be mindful of ways to store excess manure as well as process it through the periods (like winter or excessive rainfall events) when it cannot be spread.

Smaller operations (less than 100 head) often use solid systems because cows are typically housed in loafing barns or stanchions. Most solid handling systems require adequate storage because manure cannot be spread in inclement weather and field availability may be limited. Storage areas should have easy access during any type of weather and a diversion for runoff water from the area.

In their bulletin, Pfost and Fulhage add:
“Slurry systems maximize recovery of plant nutrients from manure and are often used where geologic conditions are unsuitable for a lagoon system. These systems increase the volume of manure to be handled because of the higher water content, but allow the manure to be handled as a fluid.”

Lagoons aid in the prevention of waste reaching ground and surface waters. Manure is flushed from the barn or alley into a lagoon which prevents it from seeping into water supplies. However, farm managers should be mindful of the current regulations as many lagoon systems are older and may require updates or special handling and oversight. Likewise, farms that are expanding or building a new lagoon should check the regulations in their region to ensure the new structure is compliant.

As water flushes into lagoons, it runs across a screen to capture manure solids. Water is collected in the lagoon (called effluent) and then pumped to the fields by a system of pipes as irrigation for crops.

An article from the national dairy checkoff, Lagoons Help Farmer Responsibly Manage Manure, highlights one Florida dairy that uses this method to provide a nutrient-rich and natural alternative for their crops. Then, they use these crops to feed their cattle, thus creating a beautiful circle of sustainability.

No small matter
As agriculture becomes more regulated and continues to take heat for its environmental impact, dairy farmers need to remain vigilant in handling manure. Unfortunately, many dairies have graced headlines for mishandling manure to the detriment of their neighbors and the  environment. On top of this, they have been slapped with hefty fines.

Farm managers need due diligence not just for general manure management but for careful attention to current regulations as well. Valuable resources include state Farm Bureaus, extension services and land grant universities. All are capable and willing to lend a hand by providing insight and up-to-date information.

Be sure to consult these resources and local specialists when upgrading an older system or implementing a new one to ensure you are properly set up for your area.

No matter how many or what type of livestock you raise, a manure management system should be designed and operated to prevent contamination, especially in water supplies.