Over the past couple of years, a great deal has been written about the effects of transportation (by road or air) on horses. Hopefully you have taken the time to read these articles and now have a heightened awareness of the potential stresses placed on the horse during transportation. Potential stress factors include the removal of a horse from its normal surroundings, the effects of confinement and poor ventilation, wide fluctuations in temperature and relative humidity, constant vibration and road noise, and deprivation of food and water.

The last factor is this article’s focus. No matter your destination, this information is important to your horse’s health.

One of your primary concerns when traveling is ensuring that your horse arrives unscathed and in peak fitness. Nutrition is important for optimal performance–therefore, especially when traveling (by trailer or other mode of transportation) precedes an athletic event, feeding management during and after transportation becomes an important consideration. Even setting aside the issue of athletic endeavors post-transportation, it is obviously not a good practice to deprive a horse of food and water for prolonged periods. Therefore, regardless of the reason for transportation, you need to take steps to ensure that at least some of your horse’s nutritional needs are provided while on the road.

Normal Feed/Water Intake

Before discussing how to feed and water on the road, let’s briefly review some basics concerning daily feed and water intake. Surprising as it may seem, water is the most essential nutrient. As a general rule, a sedentary (couch potato) horse requires a minimum of about 30-35 milliliters (mL) of water per kilogram (kg) of body weight per day for maintenance of water balance. That’s about 17 to 20 liters (five to six gallons) for a 1,200-pound horse. Diet, activity level, and environment markedly influence daily water requirements. Diets high in dry roughage sources (e.g., hay) increase water needs because of the water-holding capacity of fiber in the hindgut.

Sweating also increases a horse’s water requirement. Sweating is the main means by which horses lose heat during exercise; the hotter the climate, the greater the sweat losses. In fact, when it is hot, sweating becomes important for regulation of body temperature even at rest. These losses must be balanced by an increase in water intake.

Practically speaking, the horse is the best judge of his needs, and under normal circumstances he does a fine job of meeting his water requirements. Our job is to ensure that there is plenty of fresh water available to the horse. There lies the first potential stumbling block in ensuring adequate intake of feed and water on the road. It is difficult, if not impossible, to provide unlimited access to water during road transport.

As well, water losses via sweating (and, therefore, water requirements) can be much higher during transit, particularly in hotter conditions. To make matters worse, some horses are reluctant to consume water that is not from the home source. All of this serves to emphasize the potential for a horse to become significantly dehydrated during transportation.

Daily feed intake depends on many factors, including age, level of activity, and pregnancy or lactation status. However, a good rule of thumb is that your horse will need about 1.5% of his body weight in forage (hay) to maintain condition. For an adult horse weighing 1,100 pounds (500 kg), this is 17 pounds (7-8 kg) of hay. Of course, performance horses will require varying amounts of higher energy feedstuffs (e.g., grain) to meet energy requirements. Therefore, total feed intake might be in the range of 22-26.5 pounds (10-12 kg) per day.

Effects Of Transport On Body Weight And Water Balance

Horses lose weight during transport, whether traveling by road or by air. The main factors contributing to this weight loss are decreases in feed and water intake and an increase in water losses (via sweating). The magnitude of the weight loss will depend on the length of the journey, environmental conditions, the quantity of feed and water consumed during transit, and the horse’s experience with travel.

Even in cool weather conditions, weight loss can be substantial–on average, approximately 0.45-0.55% of their body weight per hour. One study in Japan found that horses lost 1.1-1.6% of their body weight after a 2.5-hour journey (80 or so miles). This represents a 24- to 40-pound (11-18 kg) weight loss for our 1,100-pound horse. After 60 hours, weight loss approached 5% of body weight (55 pounds) despite consuming feed and water during the trip. Obviously, this length of journey represents a fairly extreme situation with respect to road transportation, although the international equine traveler occasionally will encounter trips of 30 hours or more.

Environmental conditions, particularly those within the transport vehicle, play a big role in determining just how much weight will be lost during transit. The hotter it is, the more the horse will sweat in an attempt to maintain body temperature, and the greater the weight loss. Excessive sweat losses from nervousness can be a problem even in relatively cool weather (e.g., less than 40-50°F).

We often have the desire to provide our horses with a warm and cozy environment, so we close the window and air vents in the trailer and throw a heavy blanket over the horse. This circumstance creates two problems. First, ventilation and thus air quality within the trailer will be very poor. Second, the horse can overheat and sustain large sweat fluid losses. This problem will be compounded in a nervous, inexperienced horse.

A lack of water intake during transport also contributes to dehydration and weight loss. Some horses just don’t drink very well on the road, which has been shown in research studies. Even when offered water at regular intervals (e.g., every four hours), many horses consumed very little water (see Van den berg et al. 1998). Fortunately, most horses will drink heartily upon arrival, replacing most of the water deficits incurred during the trip. However, this is not always the case, and dehydration and weight deficits can persist for three days or more after a trip, particularly after a long one.

By and large, feed intake will be lower during transportation compared to the on-farm circumstance. Of course, we have total control over a horse’s access to feed. At one extreme, no food is provided during transport–this is reasonable for trips of three to four hours or less, but not for long hauls. Extended periods without food will worsen the weight loss problem and delay recovery at the other end.

The stress of travel combined with prolonged feed deprivation and dehydration also could result in gastrointestinal disturbances, such as impaction colic.

Also, consider that standing in a trailer is not at all the same as standing in a box stall. One research study showed that horses’ energy expenditure during trailering was equivalent to that needed for walking. Rough and winding roads (or poor driving) will require continuous adjustments by the horse in order to maintain his balance. This burns energy and can result in a very tired horse at the end of a long trip. Again, we can expect that horses with a nervous disposition or those with little travel experience will expend more energy and be more fatigued after a trip than the old campaigner.

All of the above is not meant to scare you from taking your horse on a trip. However, you need to be aware that shipping disrupts normal patterns of feed and water intake. The longer the journey, the greater the disruption and the longer the recovery period following transport, not to mention a much higher risk for “shipping fever” (pneumonia). Above all, you need to develop a plan to address your horse’s dietary needs during and after transport. For more on shipping fever, see “Countdown to Sydney 2000” in the July 2000 issue of The Horse, https://thehorse.com/ViewArticle.aspx?ID=211

Horse Transport Guidelines

Some of you will be aware (and hopefully have a copy) of a recent publication entitled Guidelines for Horse Transport by Road and Air. This booklet, published by the American Horse Shows Association (AHSA) and the Massachusetts Society for the Prevention of Cruelty to Animals (MSPCA), provides an excellent overview of the effects of transport on horses together with a set of rec-ommendations concerning, for example, preparation for shipping, length of journey on any given day, and provision of feed and water. The recommendations set out here are consistent with those published guidelines. If you would like to order a copy of this book contact the American Horse Shows Association at 859/258-2472 or 859/225-6957.

Preparation

Rule #1: Don’t change the diet right before or during a trip. Regardless of the length of the journey, preparation is the key to successful dietary management on the road. You need to take enough food and, if possible, water to cover the outbound and homeward trip as well as the time away. The horse’s gastrointestinal tract prefers a routine, and upsets can occur with a sudden change in diet–something that might be unavoidable when not enough feed is packed for the entire trip. Confirming what we have long suspected, recent research (see Cohen et al. 1999) has shown that changes in diet, and in hay in particular, increase the risk of colic.

Carrying enough water can be a problem and often is not feasible for all but short trips, e.g., over a weekend. However, hauling water often is a necessity for finicky horses which are reluctant to consume water that is not from the home source. Clearly, you cannot carry enough water for several horses–remember, each horse will drink five to six gallons or more per day. (Hopefully, they are not all fussy.) An alternative is to add some kind of flavoring to the “foreign” water.

Rule #2: If you plan to use flavored water on the road, try it at home first! A popular choice among horsemen is flavored drink mix. Trial and error will tell you which flavor the horse prefers.

On The Road

Rule #3: Stop at regular intervals (every four hours or so) and offer water. Trips of three to four hours or less are not likely to result in significant dehydration and there is no need to feed horses during journeys of this length. Provide fresh (or flavored) water upon arrival, and give feed when the horse is settled into his new environment. Longer journeys are a different story, so you need a plan for feed and water.

The AHSA/MSPCA guidelines state that, “Ground transport time per day should not exceed approximately 12 hours from the time the first horse is loaded on the vehicle. After 12 hours of transport, horses should be removed from the vehicle and comfortably stabled for at least eight hours.”

This recommendation is perhaps the most controversial. Regardless of journey length, some horsemen believe it is best to reach the destination as fast as possible. The downside of this approach is dehydration due to a lack of water intake, particularly during hot weather (unless the trailer is equipped with automatic waterers). Even more important is that the risk of serious illness (especially shipping fever) increases substantially when trip duration goes beyond 16 hours or so. Poor ventilation in the trailer, dusty/moldy hay, and the lack of opportunity for the horse to get off the trailer during the trip heightens this risk.

Ultimately, you must make the call regarding the maximum travel time per day. Nonetheless, the collective wisdom of veterinarians and researchers is that restricting the trip duration to 12 hours per day helps to ensure the health and well-being of the horse. This is obviously of the utmost importance, regardless of what is planned for the horse at the end of the trip.

If it will take longer than 12 hours to complete the journey, plan on a multiple-stage trip whenever possible. This will take considerable planning on your part–you will need to identify a facility that will allow you and your horse(s) to stay overnight. This needs to be a well-run operation that is free of disease problems, and one where your horse will have no or minimal contact with resident horses.

Although some trailers are equipped with automatic waterers, this is a luxury that most owners do not have. Therefore, during long trips, you must remember Rule #3: Stop at regular intervals (every four hours or so) and offer water. This also gives you the opportunity to check on the overall condition of the trailer and the horse (e.g., calm vs. agitated, whether or not he is sweated up). You might need to open or adjust windows and vents to improve air quality and lower the air temperature in the trailer. These rest stops should last 15-20 minutes or so.

Packed Lunches

Rule #4: The diet during travel should be predominantly forage-based. The horse should be fed during journeys longer than four to six hours. Conventionally, one hangs a hay net or canvas hay bag in front of the horse. However, you need to take a few precautions when feeding hay in a trailer. The haynet or bag will be hanging right in front of what’s called the “breathing zone.” The hay must be as dust free as possible to prevent the horse from inhaling dusts and molds, both of which place the horse at increased risk for infection and other respiratory ailments.

Thoroughly soak the hay in water before placing it in a haynet or bag, i.e., completely immerse the hay in a tub of water and leave it there for five to 10 minutes to ensure it is completely wet. For very long trips, you will need to prepare several bags in this manner (or refill them with pre-soaked hay along the way). While we’re on the subject of haynets or bags, try to hang these as low as possible while minimizing the opportunity for the horse to entangle his feet in the net.

Rule #5: The horse should be given as much room as possible to move his head around. Restraint of the horse in a “heads-up” posture has been shown to compromise the normal clearance of mucus from the lungs and to increase the opportunity for the establishment of a bacterial infection (see Racklyeft et al. 2000, Raidal et al. 1996, and Raidal et al. 1997).

One way around the dusty, moldy hay problem is to not feed hay at all. Hay cubes are a good alternative source of forage, and trailers with built-in mangers are ideal for feeding hay cubes. Alternatively, you can hang a plastic bucket for this purpose.

Haylage has become another popular forage with international riders. Haylage is highly palatable, and because it is very high in moisture, it has the added advantage of delivering some of the horse’s water needs. Remember, whether you substitute hay cubes or haylage on the road, they must be introduced into the diet at least two weeks before transport. (For more information, see “Alternative Forages” in the January 2001 issue of The Horse or go to https://thehorse.com/ViewArticle.aspx?ID=74.)

Whether or not grain should be fed during transport is a commonly asked question. Currently, the “dogma” suggests that the amount of grain in the diet should be reduced immediately before, during, and for a few days after transport. One concern is that a large amount of grain fed during transport will predispose the horse to colic. However, there is no scientific proof of this association.

On the other hand, for horses required to undertake high-level competition soon after arrival, a prolonged period of sub-normal grain intake might have a negative effect on performance. For the moment, it is advisable to cut the grain ration in half during transport–the amount fed can be increased to the normal daily allotment over the one- to two-day period after arrival.

Monitoring The Traveler’s Condition

The AHSA/MSPCA guidelines booklet contains samples of forms that can be used for health monitoring, including feed and water intake during and after transport. Purchase a set of portable scales so that you can measure feed intake. Likewise, use water buckets with volume markings to estimate water intake. Take measurements of your horse’s intake for a few days before the trip and compare these numbers with those collected during and after the journey.

Particularly for long trips (12 hours or more), it is a good idea to allow for a few days of recovery. Closely monitor the horse’s general attitude and appetite (by continuing to measure feed and water intake) and gradually get him back into the normal routine. In some horses, appetite is a bit below par for a day or so after long trips. Any longer than that should raise suspicion of illness and prompt you to call a veterinarian.

If you plan for your horse’s nutrition and comfort during transportation, you will arrive with a happier, healthier horse.

FURTHER READING

AHSA/MSPCA. Guidelines for Horse Transport by Road and Air. Ed. C.W. Kohn. Available through the American Horse Shows Association at 859/258-2472 or 859/225-6957.

Cohen, N.D.; Gibbs, P.G.; Woods, A.M. Dietary and other management factors associated with colic in horses. Journal of the American Veterinary Medical Association, 215: 53-60, 1999.

Racklyeft, D.J.; Raidal, S.; Love, D.N. Towards an understanding of equine pleuropneumonia: factors relevant for control. Australian Veterinary Journal, 78: 334-338, 2000.

Raidal, S.L.; Love, D.N.; Bailey, G.D. Effects of posture and accumulated airway secretions on tracheal mucociliary transport in the horse. Australian Veterinary Journal, 73: 45-49, 1996.

Raidal, S.L.; Love, D.N.; Bailey, G.D. Effect of transportation on lower respiratory tract contamination and peripheral blood neutrophil function. Australian Veterinary Journal, 75: 433-438, 1997.

Van den Berg, J.S.; Guthrie, A.J.; Meintjes, R.A.; Nurton, J.P.; Adamson, D.A.; Travers, C.W.; Lund, R.J.; Mostert, H.J. Water and electrolyte intake and output in conditioned Thoroughbred horses transported by road. Equine Veterinary Journal, 30: 316-323, 1998