Ammonia Beware
That
pungent barn smell is a sign your horse is breathing a hazardous
chemical.
Story
& Photos by Tracy Williams
|
| It
is the hallmark scent of barns the world over, a foul stench
that strikes you upon entrance… and occasionally nearly
knocks you down. Even in carefully cleaned stalls, traces of
odor remain, and many barn owners consider it an unchangeable
facet of the equine industry. But the source of odors stems
from the breakdown of equine waste, which produces ammonia –
a noxious gas that could contribute to reduced performance and
overall decreased health of your beloved stall resident. |
What is Ammonia?
Ammonia is a caustic and highly flammable gas, yet it is used
commercially as a cleaning agent, refrigerant, fertilizer
component and in the production of plastics and explosives.
In addition, ammonia is an important cog in the nitrogen cycle;
nitrogen rotates from the air to the soil and is taken up
by plants, which return it to its gaseous form. It is here
that equines play their role. Horses expel excess dietary
protein (what is not metabolized during digestion) through
their urine in the form of urea, which enters the soil to
be absorbed by plants. In evolutionary tradition, the wild
horse is no longer affected as it roams freely away from urine-soaked
areas, but the modern domesticated horse is often stall-bound
and can suffer effects. Here, when urine floods the stall,
it can seep into cracked stall mats, drains or deep bedding,
and in these dark, quiet places, anaerobic bacteria feed on
the nutrients in urea and produce ammonia, which rises to
be inhaled by you and your horse.
|
Foals are at higher risk for ammonia exposure because they
spend so much time on or near the stall floor. |
Hazards
of Ammonia
According to the U.S. Department of Labor’s Occupational
Safety and Health Administration, ammonia is a toxic, reactive
and highly hazardous chemical. Their recommendations warn
that concentrations of greater than 50 ppm can cause serious
harm to human beings. Even in the cleanest barns, ammonia
levels in equine stalls exist well above this concentration.
Furthermore, the North Carolina Department of Health and Human
Services warns that humans exposed to ammonia can suffer chronic
inflammation of airways, airway hyperactivity, and chronic
irritation of eye membranes
|
| If
human exposure to ammonia is dangerous, how much more for the
horse who breathes it in higher doses for sustained periods?
Although acute toxicity for horses is unlikely, problems crop
up from long-term, low-level exposure, according to the International
Veterinary Information Service. Researchers M.S. Davis and W.M.
Foster released a paper indicating that as little as 10 ppm
for 5 to 7 weeks can cause dysfunction of the horse’s
mucus membranes, which decreases immune response and makes the
horse susceptible to other pathogens. |
Research has shown that ammonia exposure increases airway inflammation,
which compromises racing performance. |
If a horse’s health is affected, eventually performance
will be as well. In 2001, Michigan State University’s
Equine Pulmonary Laboratory released a study, which found
that stabled young horses during training suffer respiratory
distress compared to young horses that are pastured during
training. The researchers studied two groups of horses, examining
their airways monthly for signs of inflammation. The first
group was stalled for three months, while the other remained
on pasture, and then the groups were switched. The researchers
found a significant increase in respiratory inflammation in
the stalled horses that decreased when the horses were put
on pasture. “We conclude that stabling is associated
with inflammation of both the upper and lower airway of young
horses,” they wrote. While dust and mold in feed could
have an impact, ammonia definitely plays an important role,
and respiratory distress can harm athletic ability and decrease
performance levels.
Susan
J. Holcombe, PhD, also at the Equine Pulmonary Laboratory,
released a paper on the causes of airway inflammation in horses,
noting that ammonia is linked to mucus accumulation in the
equine airway. Furthermore, Holcombe stated that mucus accumulation
is positively correlated with poor racing performance.
|
| Ammonia’s
effects are exacerbated in foals, according to Frederick Harper,
PhD and extension horse specialist for the University of Tennessee.
According to Harper, approximately 15 percent of all foals suffer
a severe respiratory disease before they are one year old, although
most occur between 2 to 6 months. Since foals spend a great
deal of time on or near the stall floor, ammonia exposure is
heightened. In addition, young foals have immature respiratory
systems, so they are increasingly susceptible to disease, according
to Harper. This makes ammonia reduction all the more crucial. |
Limit
stall time as much as possible, which will allow your horse
to breathe plenty of fresh air – and not noxious chemicals.
|
Combating
Ammonia
While ammonia’s effects are clearly harmful, its presence
is not a necessary part of your barn’s environment.
There are several steps you can take to reduce ammonia exposure
for your horse even if it cannot be completely eradicated
from your barn.
1.
Consult an equine nutritionist.
Stop ammonia at the source! While protein is important, an
equine nutritionist can help you form a diet specific to your
horse’s needs and eliminate unnecessary protein, which
contributes to excess urine production. Additionally, including
yucca schidigera in your horse’s diet will also help
prevent the absorption of ammonia in the horse’s hindgut.
2. Limit stall time.
Let your horse roam the outdoors as much as possible –
even in the cold winter months. A warm, sealed barn may seem
cozy, but it really encourages bacteria growth and ammonia
production. Not only will fresh air eliminate ammonia exposure,
but plenty of grazing and free movement will only enhance
your horse’s quality of life.
3. Ventilate.
For many horse owners, total pasture time is not an option,
but when you must stall your horse, provide adequate ventilation.
Proper air flow through your barn will provide your horse
with fresh air, distribute air evenly, regulate temperature
and moisture levels and help to remove odors and gases.
4. Clean stalls regularly.
Remove urine and wet bedding daily from your horse’s
stall and strip the stall about once a week. If possible,
remove your horse from the stall while you clean because ammonia
will be stirred up by the cleaning process.
5. Choose absorbent bedding and an ammonia neutralizing
agent.
Research has shown absorbent bedding helps to decrease ammonia
levels. In addition, consider mixing a quality neutralizing
product with the bedding to help absorb ammonia. Choose a
product that doesn’t merely mask the odors but eliminates
them by actually absorbing ammonia molecules. (see sidebars
for more information)
6. Eliminate areas where urine pools.
Karen Hayes, author of The Perfect Stall, recommends using
interlocking or seamless stall mats and sealing them to prevent
urine escaping through the cracks. Bedding, mixed with a quality
neutralizing product, can then be applied on top of the mats
for an ideal stall.
If
your barn reeks of ammonia, don’t despair! With a few
changes in your management strategies, it is possible to reduce
and even eliminate the harmful effects of ammonia on your
horse’s health and performance.
The
Question of Hydrated Lime
|
Traditionally
in the horse industry, hydrated lime has been used
to treat and freshen equine stalls to prevent ammonia
levels from rising and adversely affecting you and
your horse. However, according to the National Lime
Association, hydrated lime can also be a hazardous
substance and warrants careful use. According to the
Association, hydrated lime can cause severe irritation
and burning to the eyes – including permanent
damage if untreated – irritation and burns to
unprotected skin, and irritation to the respiratory
system. In light of this, horse owners must be extremely
careful when applying hydrated lime and might do well
to find an alternative method to treat stalls.
|
Natural
Minerals: An Alternative to Hydrated Lime |
Because
of the potentially hazardous effects of hydrated lime,
manufacturers are now producing improved ammonia-absorbing
products made up of all-natural ingredients. These products,
such as Sweet PDZ, Stable Boy, and Stall Dry, are composed
of substances like diatomaceous earth, clay, and natural
minerals, such as zeolites, that are non-toxic and won’t
irritate your horse’s mucus membranes or respiratory
system. These products, especially diatomaceous earth
and clay, are considered highly moisture-absorbent,
and the minerals trap ammonia within tiny channels in
their structure, eliminating odors and noxious chemicals
from the stall and the air.
Furthermore, these products, especially those that are
zeolite-based, make excellent composting materials and
fertilizer components. Ammonium molecules replace part
of the mineral structure, allowing the ammonia to retain
its nutrient value and become a slow-release fertilizer,
which will prevent crop burn caused by excess nitrogen.
Research
has shown these products to be highly effective in ammonia
and moisture absorption, and their all-natural content
makes them an excellent alternative to hydrated lime. |
|
References
1Davis, M.S. Foster, W.M. “Inhalation Toxicology in
the Equine Respiratory Tract.” In: Equine Respiratory
Diseases, P. Lekeux. International Veterinary Information
Service. 2002.
2Hocombe,
S.J. Jackson, C. Gerber, V. et al. “Stabling is associated
with airway inflammation in young Arabian horses.”
Equine Vet J. 33:244-9. 2001
3Holcombe,
S.J. “Epidemiology of Airway Inflammation and Mucus
in Horses.” In: (Ed.), 51 Annual Convention of the
American Association of Equine Practitioners - AAEP, 2005
- Seattle, WA, USA. Ithaca: International Veterinary Information
Service (www.ivis.org), 2005; Document No. P2662.1205.
4Harper,
Frederick. “Ammonia and Foals Don’t Mix.”
Animal Science Horse Information Series. University of Tennessee.
|
Tracy
Williams is a graduate of Colorado State University
with degrees in Equine Science and Journalism. She is
a freelance writer and photographer living in New Mexico.. |
 |
|
|
|
