Tag Archives: horse management

Grain Mites: Unwelcome Summer Visitors

While most equestrians living in temperate regions of the U.S. look forward to the pleasant weather of late spring and summer, the humidity and warm-but-not-scorching temperatures are also ideal conditions for grain mites. These tiny members of the Acaridae family are only between 100th to 300th of an inch in length and are relatives of spiders and ticks.  When conditions are ideal, these common pests can occur in large numbers in grain, hay and straw, happily eating their way through your horse’s dinner.

“Grain mites eat the germ out of any kind of stored grain products and proteins,” explains Jessica Starcevich, M.S., staff entomologist with Spalding Labs. “They thrive in high humidity. Depending on the species, this means relative humidity over 70%.”

Grain mite (drawing from Penn State Extension website).


But a mite infestation is more than just a nuisance—exposure to grain mites can cause allergic reactions in several species. Grain mites are known human allergens, and ingestion of large quantities has caused lesions in the stomach lining of cattle. While more research is needed, there is increasing evidence that grain mites, which also feed on molds and fungus and spread fungal spores throughout their environment, may play a role in triggering equine respiratory syndromes.

Because mites are so small, managers might not notice their presence—at first. But with a fairly long lifespan (mites can live up to fifty-five days) and prolific reproductive capacity (a female will lay 600-800 eggs during her lifetime), it won’t take long for their numbers to compound. An active mite infestation looks as if the grain bin (or bag) has been coated in a light brown dust. The grain itself may appear dusty, and if you begin moving bags around, the mites’ crushed exoskeletons can give off a “minty” odor.

Large numbers of grain mites gathered together resemble a yellow-orange dust. Photo Agna Rodrigues/Bugwood.org

“They are most common in regular whole grains, like oats, corn and barely,” says Starcevich. “But they can infest pelleted feed and certainly sweet feed that has oats and things mixed into it.”

When it comes to grain mites, the best defense is a good offense. Many mite-prevention techniques should already be best practices in terms of grain storage. Strategies such as never pouring new grain over old, thoroughly cleaning out and scrubbing bins in between fill ups, storing grain in airtight containers and religiously cleaning up hay chaff, mold and dust, can all help eliminate the conditions that favor grain mites.

Grain should be stored in airtight containers. Be sure to clean out storage in between bags and never pour new grain on top of old.

Additionally, take steps to reduce the humidity in your grain storage area. Consider installing a fan, using a dehumidifier or even desiccant packets (keep these away from farm pets). Grain moisture meters can be purchased from agricultural supply companies; stored grain should absolutely not read at more than 16%, and ideally will be much lower than that.

“Make sure there is no place hospitable for them,” says Starcevich. “If you can dry them out, they will die very quickly.”

During humid months, consider getting smaller quantities of grain delivered more frequently, so fewer bags are stored. With each delivery, do a careful inspection of each bag before opening it. If there is any evidence of mite activity, get that bag out of your storage area immediately—and contact your supplier.

Most grain suppliers closely watch for signs of mite activity, and would prefer to be notified as soon as possible if product from their store proves to be infested.

“Suppliers get anxious about mites, but it’s usually not their fault, as mites could have been picked up anywhere along the process,” says Starcevich. “Suppliers actively watch for mites and try to avoid getting them. But if they do, they likely have an action plan for how to take care of it.”

If, despite your best efforts, grain mites appear, don’t panic—but do act efficiently, as it is far easier to control an outbreak when the numbers are small. The most important step is to remove the infested grain from your bin, and if possible, remove the bin itself from your storage area. Contaminated grain should be thrown out, buried in an active compost pile or spread in an extremely thin layer where it will be exposed to the sun. Removable bins should be left in the sun for several days, then treated with an acaricide such as pyrethrin. If possible, do not return grain to the bin for several weeks.

“The biggest thing is to get things dry,” says Starcevich. “And keep food sources away from the mites.”

If removing the bin is not possible, thoroughly clean the entire area, paying close attention to corners, cracks and crevices, then treat it with an acaricide. Wait a week, then treat again, then wait another week before use. While this may seem like overkill (if you will forgive the pun), juvenile grain mites living in high concentrations can morph into a phase called the hypopus, which has a sucker that they attach to animals to help them disperse to new areas. During this stage, they are highly resistant to pesticides.

Finally, reach out to your county extension agent if you have further questions. Usually, consultation and even testings are free, and they will know if there is a specific outbreak of any pests going on in your area.


Book Review:  The Green Guide for Horse Owners and Riders

The Green Guide for Horse Owners and Riders  by Heather Cook

c 2009 Storey Publishing (North Adams), 231 pages

ISBN 978-1-60342-147-8

The Green Guide for Horse Owners and Riders is a super easy to read and well organized book which represents the most comprehensive summary of the concepts of “sustainable practice for horse care, stable management, land use and riding” in one place to have crossed my desk.   Depending on your previous level of knowledge on the subject of eco-friendly horse management practices, this book might alternately be too basic in some areas or too detailed in others.  In either case, though, you are likely to find references to supplemental sources which can direct you to more information.


I have long maintained that the equine industry needs to get on board with more sustainable management strategies.  Too many farms are overstocked, with destroyed paddocks/turnouts, unsightly and unsanitary manure piles and out of date protocols.  This book helps take the reader through the steps necessary to establish a different paradigm, whether starting a farm from scratch or working with facilities and layouts already in place.  Cook does an excellent job of balancing general guidelines with more specific detail.  For example, each chapter concludes with guidance to be considered for various climate regions in the US and Canada.

Manure compost bins do not have to be overly fancy.  Image from http://www.horsesense-nc.com.


Some of the strategies covered in this book include techniques for “harvesting” water from rainspouts for use as wash water or for irrigation (which, interestingly, is illegal in Colorado); several methods of composting manure; selection of sustainable and healthy building materials; reducing the use of fossil fuels, and reclamation of muddy paddocks.  In addition, there is an extensive resource list compiled in an appendix which is clearly divided into sections such as green energy, grant sources, recycling, trail riding resources, helpful government and non-government organizations, etc.

muddy paddocks
Management strategies which reduce mud will prevent your paddocks from looking like this one.

This book really is a “must read” for anyone who is interested in being a good steward of their land, or in providing guidance to someone else who is in that role.  The onus is on all of us as concerned and conscientious citizens to do a better job of implementing management practices which consider the local and regional environment.  A healthy farm means healthy horses.

5/5 stars

Blogger’s Note:  Cover image is taken from Sustainablestables.com, another great resources for assistance and tips on better horse and farm management strategies.


Caring for the Older Horse

As the caregiver for a 33.5 year old equine (who has been in my life since he was a mere lad of 16 years), I am frequently asked for insight or advice in terms of the care of the older horse.  I have to admit that in Carmel’s case, I think I have had the advantage of some good genetics—his dam was a maiden mare in her upper twenties, who was bred by a recently gelded youngster who jumped the fence.  Clearly there is something in these lines which is determined to survive!

That being said, I feel that Carmel’s longevity and good health can also be attributed to several critical care and management decisions along the way.  I have the unique advantage of basically knowing his whole life’s history, and I know that he has always been well taken care of.  With the ever improving quality in veterinary care and an increase in owner education, it stands to reason that more people will be finding themselves caring for aged horses who are still sound, happy and healthy members of the equine community.

Carmel at one of his last events at UNH, ca 2000.
Carmel at one of his last events at UNH, ca 2000.

For me, caring for an older horse has been a gift, but it has not been without its hard times too.  Once horses reach a certain age, it is a tough truth that as the steward of that animal’s well-being, you will be asked to make some hard decisions.  Horses are expensive to maintain, and it isn’t everyone’s reality that they can afford to keep a horse who doesn’t suit their personal needs anymore.  I feel quite strongly that if you make the commitment to keep a horse into their retirement years, you have an obligation to do right by that animal—which usually means that you will be doing more than just meeting the horse’s basic needs for shelter, feed and water.  It is important to know, going into it, just where your personal “bottom” is—knowing this will hopefully help ease the difficulty of making judgement calls when they come before you.

So with all that being said, here are five tips from my own personal experience caring for older horses.

Tip # 1:  Give them a job.  In my opinion, a horse which is used to competing, regular riding or even just weekly pleasure outings doesn’t do well in complete retirement.  Horses are creatures of habit and routine, and when they are used to a consistent program, it can actually increase mental stress and contribute to physical issues when their work is ceased, particularly when such a change is made abruptly.  Certainly as horses age, their job will change.  But this doesn’t mean that they don’t still have a niche to fill.  The term “schoolmaster” is frequently used to describe the experienced horse which teaches the novice.  While it is perhaps most appropriately used to describe horses trained to elite levels, I believe that the term is relative.  Carmel never competed above novice level in eventing but went on to give lessons to many beginners who learned to walk, trot, canter, and jump small fences on him, and he took several Pony Clubbers up to the D3 level, all after he “retired” at 20.  Even today at 33.5 years old, I take Carmel for twenty minute hacks a few times per week in order to provide him with some sort of structure and routine.

Tip # 2: Quit while you are ahead. A corollary note to tip # 1 is that in order for your older horse to have a job, they must retire mostly sound.  This means that it is imperative for you to be highly in tune with your horse and to fully consider the consequences of pushing them “just one more season” at a level which is becoming a physical challenge.  While we certainly can prolong the performance career of our horses through the judicious use of all means of sports medicine therapies, it is my opinion that the conscientious horse owner must always consider at what point enough is enough.  Horses which need extreme maintenance to perform at a given level should probably step it down a notch to where their job can be done without taking such lengths.  In my case, that time came when Carmel was twenty.  While he was still handling the height and width of novice fences at that point, I could tell that the effort was becoming greater and his recovery times longer. Instead of risking an injury which might result in permanent lameness, I opted to change his job.

Carmel at the age of 27, competing at the elementary level with his friend Olivia.
Carmel at the age of 27, competing at the elementary level with his friend Olivia.

Tip # 3:  Allow for plenty of turnout. We all know that horses are herd animals which are meant to travel up to one hundred miles per day or more, foraging along the way.  It is a reality in our increasingly developed and suburbanized world that our horses frequently must be kept stalled due to lack of appropriate turnout areas.  This is truly unfortunate and contributes to all manner of health and behavioral disorders.  I have been very fortunate that since owning Carmel, he has almost always been able to live in an in/out situation where he can come and go from a shelter at his own desire.  Barring that, he has lived at a facility that allowed him to be out about twelve hours per day and kept in only at night.  I really do believe that this living situation has allowed him to remain sounder in the long run, both in mind and body.  Arthritis never had a chance to really establish itself in his joints in a debilitating manner, and his lungs remain clear due to good air circulation.  My horses go out every day for at least a little bit, even in extreme weather –and what is funny is they almost always choose to go outside in spite of it.  I do not think that we do them any favors by locking them in for our benefit.  So long as they have an accessible shelter if they need it—let them be out!

Carmel enjoying some time outside after the Blizzard of 2015.
Carmel enjoying some time outside after the Blizzard of 2015.

Tip # 3:  Provide routine veterinary care. Older horses require the same regular veterinary care that any other horse receives—but having a good relationship with your veterinarian can help you to customize their care to suit your individual needs and situation.  For example, your older horse still needs to be vaccinated each year, but some of the risk based vaccines may no longer be a priority.  This is important if your horse is one who has had a history of mild or moderate reactions to vaccination.  Annual monitoring of your older horse’s bloodwork can give you a baseline from which to compare results if your horse begins to seem a bit “off”; it can also allow your vet to notice changes in the function of the body’s systems early.  Many older horses end up developing pituitary pars intermedia dysfunction, or PPID (usually called Equine Cushing’s Disease), which often causes symptoms such as an extremely heavy hair coat that is slow to shed, a cresty neck, abnormal fat deposits and sometimes hoof abscesses and laminitis.  Confirmation of this disorder is done via blood test completed in winter, spring or summer.  For most horses, Cushing’s can be regulated through the use of diet modification, exercise and medication (pergolide)—but you will need to work closely with your vet.  Older horses also need routine dental care, but as they age and the available tooth decreases, they may not need regular floating—your vet or other qualified dental professional can advise you on your horse’s specific needs.

1998 or 1999.  I wish I could get his tail that long again!
1998 or 1999. I wish I could get his tail that long again!

Tip #4:   Give them a little attention every day. Just because you may not be riding your older horse as regularly doesn’t mean that daily attention isn’t important.  At a minimum, I always pick out feet every day and do a once over of Carmel’s entire body. In the winter, blankets come off at least every other day, but preferably daily, to check on body condition. (Blogger’s Note:  To blanket your older horse or not is a topic for another blog—I have chosen to blanket Carmel due to his tendency towards being a hard keeper and also because his PPID can cause thermoregulatory challenges.)   Even as Carmel’s activity level has decreased over the years, I have still religiously groomed him every day.  I think this is important for so many reasons—it is a way for me to keep my bond with him, and because I am in close contact with him, I notice the tiniest changes in his attitude or way of being.  Grooming promotes circulation and stimulates the oils of the skin to come to the surface, and for horses who are struggling to shed, regular grooming can help ease the process.

Tip # 5: Feed the right amount of a quality feed.  Older horses can be challenging to keep at an appropriate body condition.  Some are easy keepers and they need little to no grain to maintain a healthy weight.  Others, like Carmel, tend more towards being too thin and therefore careful feed management is necessary in order to keep them in good physical shape.   There are numerous senior feeds on the market which are formulated to meet the needs of an older equine.  They tend to be palatable, fortified, extruded and complete—meaning that if your horse struggles to chew forages, the senior feed can be used as a sole source of nutrition.  Most also dissolve easily in water to make a mash for those horses whose teeth are not up to the task of chewing.  Something I learned along the way is that senior feeds are meant to be fed at a much larger quantity than regular feeds.  We are so conditioned to feed “little and often” that it can be hard to understand that as much as five pounds of senior feed can be fed at one meal, with as much as fifteen pounds per day being totally reasonable and safe to feed.

Carmel snacking in 2012.
Carmel snacking in 2012.

Final Thoughts

The truth is that taking care of older horses is mostly about continuing to practice good horsemanship and to attend to their basic needs with the same level of attention to detail as for a competition horse.  Certainly the onset of age related conditions will require some modifications to their riding schedule and maintenance plan, but with quality care the older horse can remain a productive and happy equine citizen well into their golden years and beyond.