Strategies to Reduce your Horse’s Chance of Colic

Posted on by — Leave a comment

Written By Dr. Kris Hiney

Last month I encouraged all horse owner’s to develop a preparedness plan in the event their horse colics.  This month we will discuss strategies that will hopefully minimize the chance that you will need that plan.  We will discuss feeding strategies as well as other important management techniques that will help keep your horse happy and healthy.

Feeding your horse properly is one of the easiest ways to help prevent episodes of colic.  Remember  the digestive anatomy of the horse, with its small stomach and large hindgut for digesting forage does not often fit well with  modern management practices.   The horse is designed to forage continuously throughout the day, typically for almost 18 hours.  This provides a continuous input of material to the hindgut without overwhelming the stomach.

1.Maximize intake of good quality forage.

To mimic nature, ideally a horse should consume 2% of its body weight in high quality forage per day.  This allows the best match to the horse’s normal feeding strategies.  Remember high quality forage does not necessarily mean rich or high energy forages which can lead to obesity.   Simply put, high quality hays do not contain molds, potentially toxic weeds or insects, or are not excessively coarse and stemmy.  Of course, toxins and molds can easily cause digestive upsets or result in feed refusals.

2.Avoid very coarse hay or staw as feed.

Excessively coarse hay may be harder for the horse to masticate and may lead to impactions.

3.Prolong feeding/chewing  time.

If your horse needs to consume less than 2% of its body weight due to the need to maintain proper body condition, using a slow feeding hay net will help prolong the horse’s feeding time.  As we increase the amount of time the horse spends chewing, more saliva will enter the stomach and buffer the acid that is continually secreted.  As horses only salivate with oral stimulation, this increase in chew time is extremely important.  This helps to maintain a healthy stomach and avoid ulcer formation.

4.Split up concentrate meals to smaller portions.

If the horse needs substantial amounts of concentrates in order to maintain body condition or support athletic performance, be sure to spread feedings into smaller amounts.  High volumes of concentrate may overwhelm the horse’s ability to digest it properly in the small intestine.  When concentrates escape to the hindgut they are fermented by a type of bacteria which produces organic acids and lowers the pH of the horse’s gut.  By lowering the volume fed at one time, this will avoid fluctuations in pH of the horse’s tract and promote a healthier population of microflora.

5.Slowly introduce new feeds.

If new types of feeds are to be introduced to the horse’s diet, be sure to do so gradually to allow time for bacteria to adjust.   Due to the ability of bacteria to either proliferate or reduce in population with changes in substrate offered to them, a change in the horse’s diet can wreak havoc in bacterial populations. Often this is what results in the overproduction of gas, a frequent cause of colic.

6. Maintain a consistent feeding schedule.

If your horse does not have free choice access to hay or pasture, be sure to maintain a consistent feeding schedule.  Horses are certainly creatures of habit that do best with consistent schedules.  This will avoid periods of time with the horses’ stomach in an unnatural empty state, or overeating due to excitement of feeding.
7.Avoid feeding horses off the ground.

Ingestion of sand can lead to the development of impactions or colitis from irritation of the gut wall.  Routine feeding of psyllium can aid in sand removal from the hind gut.  Feeding off the ground will also limit the exposure to parasites which are a frequent cause of colic through either blockages or disruption of blood flow.

8. Practice strategic deworming and parasite management.

Regular parasite control is therefore key to colic prevention.  Remember from previous articles that this does not mean indiscriminate deworming of horses without knowledge of their true parasite load.  In fact, an increase in colic in young horses due to ascarid impactions may be in part due to the anthelmentic resistance occurring in these worms.   Rather, remember to follow strategic deworming practices in consultation with your veterinarian.   Follow good pasture management practices and avoid overgrazing. This will help to limit your horse’s exposure to parasites.

9. Allow adequate water intake.

As winter approaches, it is especially important to remember that proper water intake is vital to maintaining normal flow of digesta through the horse’s tract.  Normally horse’s drink about 8-12 gallons of water per day.  We often think about increasing a horse’s water intake when it is hot or the horse is heavily working, but fail to think about water intake in the winter.  Horse’s actually don’t like cold water, and will greatly reduce their water intake if not offered warmer water.  Providing a heated bucket or tank will encourage your horse to drink water at the same rate throughout winter.  Be sure that it isn’t sending off any stray shocks however!  That will easily lead to dehydration as the horse is too frightened to drink!  You can also increase a horse’s water intake by offering a mashed feed.  Don’t forget however not to rapidly alter his diet!

10. Provide regular dental care.

While all of these tips primarily refer to the feeding management of the horse, other factors can influence his risk of colic.  Providing regular teeth maintenance will allow your horse to chew his feed properly.  As mentioned previously, coarse hay or poorly chewed hay can create impactions in the horse’s tract.

11. Exercise the horse on a consistent schedule.

Regular exercise for stalled horses is equally key.  Horses naturally travel several miles per day while foraging. We have created a rather artificial, sedentary life style for most of our horses. It is up to us to help provide a form of regular exercise and stick to a schedule.  While this may be difficult owners, it truly is best for the horse.   In fact, some companies are working towards creating automatic feeders which force a horse to travel through its paddock to obtain its feed. Such systems also have the added benefit of prolonging feeding time as well.

Next month we will discuss additional management strategies that will reduce your horse’s risk of colic which are linked to your horse’s lifestyle, breed or even sex!

 

Pasture Grasses and Grazing

Posted on by — Leave a comment

Written By Dr. Kris Hiney

This month we will review research concerning pastures and foraging behaviors in horses. Most horsemen would agree that horses grazing at pasture represent the most natural way to feed a horse.  Certainly it represents the most economical and the least labor intensive method of feeding.  However, many owners have questions related to what or how much a horse’s is consuming when its primary source of feed is pasture grass.

This ambiguity of how much grass a horse may consume makes selecting additional concentrates or supplements more of a challenge.  In addition, many horses clearly volunteer to consume pasture grass well over their nutritional needs making regulation of body condition score very difficult.   The range of dry matter intake of horses on pasture has been reported to be as wide as 1.5 to 3.1% of their body weight in a 24 hour period. Usually young horses and lactating mares will be on the upper range of intake which would make sense due to their nutritional demands.   Mature horses are reported to typically consume 2-2.5% of their body weight in dry matter.  However, it does appear that many of our equine friends have failed to adhere to book values when given the opportunity.  A recent study looking at weight gain in pastured ponies found that on average the ponies consumed 3.8% of their body weight in dry matter, with ranges of 2.9 to 4.9%.  Others have also reported horses consuming as much as 5% of their body weight in dry matter! It is rather easy to see why horses can quite easily gain weight on pasture.

But what about horses which are only turned out for part of the day in an attempt to control feed intake? Is this an effective technique or do they simply manage to eat faster in their allotted grazing time?  In a study which attempted to determine how much a horse can consume in an 8 hour period, horses were individually assigned to small paddocks, allowed to graze for four hours, then switched to a new paddock for an additional 4 hours. The small paddocks were then harvested to determine how much the horses consumed in the given time period. In this experiment horses were able to consume 1.3% of their body weight within an 8 hour period.  In addition, their consumption rate was twice as high in the initial four hours the horses were allowed access to grazing. Therefore the horses were able to consume almost 1% of their body weight in just four hours!  Thus even limited grazing can easily result in weight gain.  From this data the authors concluded that for these particular grazing horses, only 9 hours of grazing was necessary to meet their energy needs.


While we know that good quality pasture can easily meet a horse’s maintenance requirements, does it provide additional benefits to the horse?  In a study designed to look at the effectiveness of pasture turnout in maintaining fitness, horses which has been ridden 1-2 hours per week, 5 days per week for 12 weeks were then stalled, continued to be ridden or were turned out in a large pasture.  After a 14 week period, all horses participated in a standard exercise test.  This proved that the horses allowed free access to wander through a relatively large pasture maintained their fitness compared even to the horses ridden 5 days per week.  Thus pasture turnout seems to be a reasonable solution during down time when the horse is not ridden for maintaining fitness. The pastured horses in this study traveled on average 10 km a day compared to 5 km per day in the horses which were ridden.  This study again lends support to the value of pasture turnout.

So what if we want the fitness benefit of pasture turnout without the obesity inducing over consumption?   Often the traditional answer has been to employ a grazing muzzle. In a study looking at intake rates in ponies wearing muzzles compared to their non-muzzled counterparts, muzzling resulted in an 83% decrease in overall intake. However, in just three hours, the non-muzzled ponies were able to consume 0.8% of their body weight in dry matter.  This is quite similar to the observations in the previous studies.  In addition, the same team of researchers found that the ponies “grew wise” to their limited access to grass and learned to increase their consumption rates during their restricted period.  Therefore limited time on pasture may not be as effective for foxy ponies once they learn what you are up to!  So what is our take home message?  Allowing horse’s time to graze is very beneficial, not only for their mental health, but also for their physical health.  However, in order to control intake and thus body condition score in our enthusiastic eaters, we made need to employ additional measures such as limited turnout or grazing muzzles.