Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Composting may be alternative in wake of horse slaughter bill

The American Horse Slaughter Prevention Act, making its way from the U.S. House to the Senate, could leave thousands of horses with no final resting ground.

Composting may be an environmentally friendly option that fits in the "circle of life" frame of mind and may be less emotional, two area researchers said.

On Sept. 7 the House approved the Act, which bans the slaughter of horses for human consumption by a vote of 263-146. The Senate has yet to schedule the issue for consideration.

Approximately 90,000 horses, or 1 percent of the U.S. horse population, is slaughtered annually, said Dr. Lance Baker, West Texas A&M University associate professor of animal science.

"If they don't go to slaughter, they will have to go somewhere else," Baker said.

The options for dealing with a carcass are burial, rendering, landfill disposal, incineration, composting or bio-digesting, he said. Many of these are costly, and a horse owner often has to pay to put the horse down and for its disposal, instead of getting money for the animal.

Large-carcass composting is a growing and accepted practice among feedyards and dairies, said Dr. Brent Auvermann, a Texas Agricultural Experiment Station agricultural engineer who has researched the process for about five years.

"Since we had already done some work with dairy cattle, which weigh about 1,400 pounds, a quarter horse at 1,000 pounds wasn't much different," Auvermann said. "The main thing is: the larger the carcass, the higher the stakes. It is critical that whoever does it, does it right."

Auvermann, Baker and West Texas A&M graduate student Laurie Brown began conducting a composting trial on horses last winter, using dead horses that would otherwise have gone to the landfill. The horses were provided by area veterinarians .

The trial tested three different "recipes" of composting material designed by Auvermann: 100 percent stall cleanout (horse manure and bedding); 50 percent cattle manure and 50 percent waste hay; and 50 percent stall cleanout and 50 percent cattle manure. He said he prefers the two mixes to the 100 percent stall cleanout.

Large animal composting works best if pre-composting of the material has already been started before the carcass is added, Auvermann said. The carcass is laid on a bed of chopped hay and then covered completely with the composting material.

From that point, moisture is a key, Auvermann and Baker said. Auvermann said it would be better to err on the side of too dry than too wet.

"Add water until a handful of the mixture squeezed hard doesn't result in droplets of water, but does leave a sheen of water on the glove," he said.

A good indication the composting process is working correctly is temperature, Auvermann said. The temperature should start rising within 12 to 24 hours and reach a level between 131 degrees Fahrenheit and 155 degrees Fahrenheit and stay in that range for several weeks to a month.

The temperature should be taken with at least a 48-inch temperature probe and taken in several locations throughout the pile, he said.

In the studies, the pile was turned at three months, at which time Baker said only a few large bones were identifiable. By six months, nothing was identifiable.

The optimum time to wait before making the first turn with larger animals is five to six months, Auvermann said. A large carcass will take from seven to nine months to compost completely, at which point it can be used as a fertilizer on agricultural ground.

The phosphorous level will be about 20 to 25 pounds per dry ton. It will have some nitrogen, but might contain less than 20 pounds per dry ton or, if the recipe is right, up to 35 pounds per dry ton, he said.

"This is well suited to cotton in terms of the nitrogen-phosphorous ratio," Auvermann said, adding cotton gin trash would be an excellent ingredient to put into the composting mix.

The compost must go through three phases before it is a valuable product, he said. The final phase, curing, is important because it lets the last intermediate compounds be converted to non-phytotoxic compounds.

"Maturity testing is a good idea," Auvermann said. "When you put compost on plants, if it is not mature, it may compete with the plants for nitrogen. It also can kill the plant if it is too hot with phytotoxic compounds."

He suggested trying a small amount with potting soil in a seeding tray to see if the seed would germinate and grow, or using a maturity test kit.

Auvermann said several other options for the composted material would be to be used as a Class A biosolid for roadways and to help establish turf grass, or it could be used in the bioenergy arena. The material could be gasified and burned after it is composted.

Both Auvermann and Baker said the small individual horse owner might not see composting as an option, but a large, centrally located commercial composting operation would offer a service to area horse owners and veterinarians.

"Without renderers to go to, this could become a big market," Baker said. "If you look at it environmentally and politically, it works. It's the whole circle of life thing. You grow the grass to feed the animals and then turn around and use them to do the same thing for the next generation."

Dr. Brent Auvermann | EurekAlert!
Further information:

More articles from Agricultural and Forestry Science:

nachricht Forest Management Yields Higher Productivity through Biodiversity
14.10.2016 | Technische Universität München

nachricht Farming with forests
23.09.2016 | University of Illinois College of Agricultural, Consumer and Environmental Sciences (ACES)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>