- Feb 1, 2006
There was a time when bedding for horse stalls received little attention or discussion, especially in the agricultural Midwest. When horses provided the power for planting and harvesting crops, almost every farm had a field of oats. The oat kernels provided nourishment for the horses and the straw provided bedding.
It isn't that simple any more as horses have been removed from agriculture and have become recreational animals. Today, there are a variety of forces and motivating factors at work concerning bedding. Oats, for example, is no longer a staple crop on many farms. Also, the spread of horses into urban areas has spawned a whole new set of concerns about the handling of horse manure. In addition, concerns for problems such as COPD (chronic obstructive pulmonary disease, or heaves) have stimulated the development of new, dust-free bedding products. As a result, providing safe, clean bedding for horses has become an industry unto itself.
Straw--oat, barley, and wheat--is still used in many barns across the country, but there are other options. They include wood shavings, shredded paper, hemp, cardboard, wood fiber, wood pulp, wood pellets, kenaf, peat moss, and a combination of earth and clay. In this article, we'll take a look at each of them.
Product Claims and Research
While manufacturers have tested their products and made claims as to their efficiency, there haven't been many scientific studies conducted on the merits, or lack of same, of various types of bedding.
One study took place at the University of Maine about five years ago and involved comparing what then was a relatively new product--wood pellets--with sawdust for bedding. The chief investigators were Donna Lamb, MS, Piscataquis County Extension Educator, and Richard Kersbergen, MS, Waldo County Extension Educator. The research was conducted at the University of Maine using the university's horse herd.
There were a couple of reasons for conducting the study, said Kersbergen in his report. At that time there were 17,000 or more horses in a growing equine population. Bedding for stalls was becoming more difficult to locate and more expensive.
For example, Kersbergen explained, while oats are grown in parts of Maine, it often is used as a rotational crop with potatoes. Basically, he said, it is worth more to the farmer to return the straw to the soil for enrichment than to bale and sell it. Maine also is noted for its forestry products, but Kersbergen said many of the byproducts, such as shavings and sawdust, are being converted to fuel for heating homes. Thus, there was economic motivation to find a bedding material that was affordable, safe, and efficient.
Lamb was the chief investigator, and she said she first saw wood pellets being used in horse stalls during a visit to the state of Washington. She returned home and applied for a research grant from the Maine Agricultural Council, which was approved.
The pellets used in the study, she said, came from a commercial supplier and resemble those used in pellet stoves, except for being more coarse and absorbent. The pellets utilized in stoves were not used, she said, for fear they might contain black walnut, which can cause laminitis.
The product used in the study was described by the manufacturer as being 100% biodegradable, sterile wood fiber, containing no additives. The pellets begin as raw, white, soft-wood shavings and sawdust. They are subjected to an extreme heat processing that removes all oils, tars, acids, and resins from the wood. They leave the processing plant as a granulated product that expands to three times its size when water is added. The water is added when the pellets are first placed in the stall to facilitate the fluffing process.
In a report, Lamb and Kersbergen presented some statistics that point out that manure production and removal are major considerations in the equine industry and that the type of bedding used plays a key role. Here is what they had to say: "The Maine Nutrient Management Training Manual estimates that horse manure and bedding is produced at a rate of 75 pounds or 3.7 cubic feet per animal unit (1,000-pound animal per day) in full confinement. This document also estimates the average animal weight for horses at 1,000 pounds. If we estimate that horses are maintained in confinement 50% of the year, then the estimated volume of manure produced by equines in the state of Maine would be 116,344 tons or 425,127 cubic yards per year."
One of the first things the researchers learned was that the wood pellets cut down on the volume of manure. In this case, manure is described as being excrement combined with the bedding it contaminated.
An interesting side finding in the study was that mares and geldings produced different amounts of manure on different types of bedding. Mares produced less manure with sawdust bedding than geldings, and geldings produced less manure with pelleted bedding than mares. However, both mares and geldings produced less manure with pelleted bedding than with sawdust.
Combined, all horses involved in the six-day study produced an average of 58 pounds or 1.12 cubic feet of manure on sawdust each day, compared to 43 pounds or 0.72 cubic feet of manure on pellets. Thus, the weight of manure removed per day from pellet-bedded stalls was 15 pounds less and 0.4 cubic feet less than the manure from sawdust-bedded stalls.
"If this were extrapolated over a year," the researchers reported, "it would result in 2.7 tons or 5.4 cubic yards less manure per horse that would need to be disposed of by the horse keeper."
The investigators also determined cost differential. The initial cost of the pelleted bedding for the project, they said, was 15 times more expensive than the sawdust bedding on a weight basis, and six times more expensive on a volume basis.
The product--pellet or sawdust--that would be most suitable in the long run, Lamb said, would depend, in part, on the operation and goals of the owner. Pelleted bedding, she said, made for a neat and tidy facility because of its absorbency and reduced volume of manure compared to sawdust. In some operations, she said, this might override cost considerations.
Manure storage structures, she added, could be significantly downsized with pelleted bedding.
The pellets were easily handled and stored, she said, because they arrived in weather-proof, 40-pound bags, while the sawdust arrived by truck in bulk form. In the five years since the study was conducted, Lamb said, there has been at least a slight increase in the use of wood pellets over sawdust in her area. Although pellets continue to be more expensive than sawdust, she said, some stables feel their efficiency outweighs the cost differential.
Straw, in some parts of the country, is readily available and cost-effective. There are some downsides--its fungal spores can induce allergies, and some horses will eat straw bedding. It also can become soggy with urine and fecal matter and heavy to handle. This is especially true of oat straw.
Wheat straw can be a bit more efficient than oat straw. The trick is finding wheat straw of high quality. Straw sometimes is chopped and the dust extracted, making a much more efficient bedding material than long-stemmed straw. It is estimated that cut oat or wheat straw will absorb up to 25% more moisture than long-stemmed straw. The downside is that chopped straw sometimes is dusty unless the dust is extracted.
Barley straw often is of better quality than oat straw, providing that its awns (the flowering bristles) are removed. If they are not removed, they can irritate a horse's skin.
Wood Shavings and Sawdust
Baled and packaged wood shavings have become popular through the years, while sawdust seems to be losing favor. The important thing is that both shavings and sawdust be from soft pine rather than from hardwoods. Softwood is twice as absorbent as hardwood. Green wood has only 50% of the absorptive capacity of dried wood.
If hardwoods are used either in shavings or sawdust, care must be taken to make certain that black walnut is not involved. Black walnut contains a chemical called juglone that some researchers believe can cause laminitis from either ingestion or skin contact and, at the least, can cause swelling of the lower limbs and irritation.
Both shavings and sawdust can be dusty. However, shavings also are available in a dust-free form at a higher cost.
This type of bedding often is made from old newspapers. It is absorbent, but the downside, as with oat straw, is that it can get heavy when wet and soiled and is hard to muck out. A more minor downside is that newspapers have ink that can sometimes stain the coats of gray horses. That being said, some shredded paper bedding is comprised of unprinted white paper.
One manufacturer of cardboard bedding reports that corrugated, clean, recycled waste cardboard is used in the shredding process. It also goes through a dust extraction process, which results in a contamination-free end product that is biodegradable, dust-free, and particularly beneficial to horses with COPD. The product, generally speaking, is marketed in baled form.
Dried hemp is derived from the flax plant and in some areas is available in dust-free bales. It is described by proponents as being attractive, comfortable, and cost-effective. The downside is that it can cause digestive problems, such as colic, when ingested by horses.
Peat moss is decayed organic matter that has formed over thousands of years in wetlands. There seems little argument that it is one of the most effective bedding materials, in both stable and horse trailer. There is an important downside--many environmentalists insist that peat removal can damage wildlife habitat. The end result is that peat moss is not in widespread usage as horse bedding.
Wood fiber is made from waste softwood material and is dried and shredded. It offers a bedding material with low dust levels and high absorbency. One manufacturer advertises that a 30-pound bag of its wood fiber product will absorb approximately 120 pounds of urine.
This is similar to wood fiber and is produced by drying the wood at extreme temperatures. It is a byproduct of the wood pulping industry.
Earth and Clay
This particular product is composed of a natural blend of diatomaceous earth and clay. The manufacturer maintains that it has the ability to neutralize ammonia and absorb odors as well as moisture. It is described as being safe for use on dirt, wood, concrete, metal, or rubber surfaces. It is not caustic and is non-toxic. For at least one processor, the material comes from a mine site in Canada.
One of the newer products on the market is bedding made from the kenaf plant. The plant is described as being of a fibrous nature, related to cotton and okra. It is an annual plant that can grow 12 to 14 feet in height, but typically is six to 12 feet high, depending on soil content and moisture. After a growing season of four to five months, the kenaf stalks are allowed to dry in the field for 30 to 45 days in a process called "retting." The kenaf is then baled in large bales and processed.
The core fiber is said to be similar to balsa wood in weight and texture, and it is the part of the plant used in bedding. The qualities of the core fiber of kenaf include being porous, spongy, and minimally compressible. The manufacturer says it takes three to four bags containing 2.8 cubic feet each for a basic bedding layer. From then on, it is advertised, it requires about one such bag per week to replace removed manure.
There are other options in the bedding department, such as ground corncobs and ground hay, but those listed earlier are among the most popular and practical.
With the wide variety of bedding materials available, there are many choices for horse owners to select the right bedding to suit their needs, and the needs of their horses. There are now more choices for reduced dust, or dust-free, bedding for horses with respiratory ailments, or for owners who want a cleaner environment for their animals.
About the Author
Les Sellnow is a free-lance writer based near Riverton, Wyo. He specializes in articles on equine research, and operates a ranch where he raises horses and livestock. He has authored several fiction and non-fiction books, including Understanding Equine Lameness and Understanding The Young Horse, published by Eclipse Press and available at www.exclusivelyequine.com or by calling 800/582-5604.
POLL: University Equine Hospitals