Do’s and Don’t(s) of preparing
your horse for Transport

1. Do make sure the horse is healthy.
2. Do make sure the horse has had free access to feed and water up until the time of travel.
3. Do make sure the horse is tractable and taught to lead.

1. Don’t limit access to feed and water prior to travel.
2. Don’t administer any medications (worming etc) 48 hours prior to travel.
3. Don’t rug the horse during transport.
4. Don’t stress the horse prior to travel (weaning, hard work).

Below is a summary of some recent scientific research and how we at Equine Answers work towards combating these issues.

Welfare issues relating to the
road transportation of horses.

Introduction

Transporting horses to competition is a necessary fact of life and there are as many theories on transporting as there are transport methods. It goes without saying the transport vehicle needs to be checked for safety and mechanical soundness (Smith et al. 1996). Transport to competitions needs to be planned well to minimize the effects on the individual. The welfare issues related to horse transport include; the energy cost of transport, ventilation and air quality, injuries related to travel (falls, bumps, cuts etc), orientation during travel, dehydration and gastro-intestinal tract disturbances. Data collected has clearly shown physiological responses of horses undergoing transport including changes in muscle metabolism, stress indices, dehydration and immune parameters, and body weight. These measured responses may increase disease susceptibility (Stull et al. 2004) and have impacts upon the energy availability for athletic performance following transport of horses (Stull & Rodiek 2000).

The energy cost of transport

Recent research has shown that the energy cost of transportation is similar to the energy cost of walking for the same period of time (Marlin & Nankervis 2002). This is probably of not much importance for shorter trips, under 3 hours (Marlin & Nankervis 2002), however for longer trips it can have significant affect on the subsequent performance levels of the individual. In Australia, the vast distances covered to attend competitions make this an important consideration when planning the trip. A road trip from Brisbane to Adelaide will take about three days allowing for rest stops but will involve approximately 24 hours ‘on the road’, which equates to a considerable energy cost that needs to be replenished before the competition can begin. Recent research has shown that although absolute heart rate is a reasonable indicator of stress levels during transport, heart rate variability is a more sensitive measure of the stress levels during road transport (Ohmura et al. 2006).

At Equine Answers we are very conscious of the energy cost of transport and try and minimize the amount of time each horse spends on the truck per day.

Dehydration during transport

Dehydration is an important factor to be considered as most horses are transported without free access to water. Horses will lose approximately 0.4-0.5% of body mass per hour of transport (2kg per hour for the 500 kg horse) this can be increased to as much as 1.5% of body mass per hour if the horse is transported in less than ideal conditions ( high temperature and humidity, bad driving, inexperienced traveller) (Marlin & Nankervis 2002). Transporting healthy horses for more than 24 hours without access to water in hot conditions will cause severe dehydration(Friend 2000). Dehydration can be related to 4 major causes during transportation (1) decreased water intake (2) increased sweating (3) increases in water content of faeces and (4) increased insensible losses (Marlin & Nankervis 2002). A study by Friend (2000) compared dehydration and stress levels of transported watered horses, transported non watered, penned watered horses and penned non watered horses. He found that weight loss was greater in the non watered groups than in the watered groups, interestingly the penned group had a higher percentage bodyweight loss than the transported group (12.8% v. 10.7%). These results compared to the watered groups (3.5% v. 4.0%) show that periodic access to water significantly decreases the bodyweight loss during transport. These measurements combined with various stress measurements (HR, RR, Blood tests) confirmed the assumptions made from the bodyweight results that transporting horse in hot conditions will cause severe dehydration. Further to this study an onboard watering system (Iacono et al. 2007) for the transport of slaughter horses in America was trialed. Although most of the horses (85.7 – 100%) drank during the shipments this only resulted in a trend (P=0.07) for horses with access to water to loose less weight than the non watered control group (9.83kg/horse v. 17.4kg/horse). This suggests that the horse did not consume that much water.

Although the study by Iacono et.al (2007) did not produce statistically significant differences, the temperature ranges were relatively cool for two of the groups (mean 20 and 18 deg C) with the third at 30 deg C.. There is no mention whether these temperature measurements are external readings or internal readings which could have an effect on the dehydration rate especially in the hotter climates with the internal temperature being approximately 6oC hotter than the external temperature (Purswell et al. 2006). These findings coupled with the findings of Friend (2000) suggest that transporting horses in hot climates for extended durations compromises the dehydration status of healthy horses, and therefore during transport care must be taken to minimise dehydration.

Our overnight stabling facilities that we use are clean and comfortable. The amount of water that each horse drinks during stops is carefully monitored in particular during the hotter times of the year. During the hotter months we try and travel mostly in the cool of the evenings and morning and have stops during the middle of the day. We also carry molasses to add to the water to encourage drinking.

Ventilation and air quality

The respiratory system is probably the most vulnerable system of the horse under transportation stresses. Dehydration will decrease the systems ability to clean itself due to decreased mucus production and this coupled with an increased concentration of allergens and ammonia from urine, due to restricted ventilation, can severely impact the respiratory system (Marlin & Nankervis 2002). The common practice of restraining the head during transport also adds to this problem by not allowing the horse to lower its head to drain the mucus from the nasal passages. Stull and Rodeik (2002) in comparing the respiratory health of horses transported for 24 hours either cross-tied or loose recommended that horses during long term transportation be allowed to travel loose in small compartments rather than cross- tied.

Purswell et.al (2006) studied the air exchange rate in a four horse trailer and found that even with all the vents and windows open, at 97kph, the ventilation within the trailer was not adequate when compared to the recommendations for stabled horses. The most cost effective means of increasing the ventilation within the trailer is increasing the number of, or size of, the vents and windows. Marlin & Nankervis (2002) suggest that using dust free bedding (shredded newspaper) moistened feed will have a positive effect on air quality by reducing dust and irritants and therefore will reduce the impacts upon the respiratory system.

Therefore in reducing the impact on the respiratory system the trailer must be well ventilated, transport the horse with no head restraint, reduce the dust in the trailer by wetting the feed and using a dust free bedding.

The ventilation in the trucks is excellent with open slats down each side of the truck and a series of vents trough the roof to aid in the circulation. During transport we DO NOT tie horses as this restricts the ability for the horse to lower its head and drain the nasal passages. It is for this reason that we do not have chest boxes installed in our trucks.

Orientation during transport

Orientation of the horse during transport has been the point of major discussion among horse enthusiast for many years. This question has been the focus of a reasonable amount of research however the results appear to be contradictory mainly because of differences in trailer design and the lack of simultaneous comparisons(Toscano & Friend 2001). In this study by Toscano and Friend (2001) when comparing forward facing to rearward facing they found no statistical difference in horse movement due to orientation, however they did note that individual characteristics may play a large role in horse maintaining balance during transport.

Clark et al (Clark, Friend & Dellmeier 1993) in measuring heart rates and hormone concentrations concluded that orientation had no significant effect on these measurements during transport however observations taken concluded that rearward facing horse had fewer side and total impacts and losses of balance than forward facing horses. This led to the conclusion that facing horses away from the direction of travel may be advantageous because of their improved ability to maintain balance (Clark, Friend & Dellmeier 1993). Waran et al (Waran et al. 1996) in a comparison between rearward and forward facing transport found that the average heartrate was significantly lower (P<0.05) when facing backwards. Although this finding differed slightly from the Clark et al (1993) study both studies concluded that the horses appeared to find the rearward facing direction of travel less stressful.

Gibbs et al (Gibbs & Friend 1999) in examining the preference of horses orientation during transport found a slight preference for horses travelling on a 450 angle with no preference between rearwards and forwards facing with the balancing ability of the horses not meaningfully affected by the orientation.

From these studies it would seem that horses found the rearward direction of travel less stressful than forward facing, however individual characteristics may play just as an important role in stress levels during transport. This stress my also be lowered if the horse is actually trained to being transported(Shanahan 2003).

We employ the reverse angle orientation in our trucks. The horses heads are towards the passenger side of the truck, away from oncoming traffic. This way of loading gives the horses the longest bay possible and with the dividers being fully adjustable, this allows us to vary the width of the bay to gain that happy medium between being too tight and offering no support.

Conclusions

In considering the physiological effect of transportation to attend competitions there are several key factors to consider:

• The energy cost of transport – under 3 hours little effect on energy levels for competition however for longer trips the energy cost of transport must be taken into account before the actual competition is commenced.
• Dehydration - the level of dehydration will depend largely on the travelling time and the ambient temperature. In less than ideal conditions horses may lose up to 1.5% of their bodyweight per hour resulting in severe dehydration in a short time. The access to water during travel is important to minimise dehydration and the negative effects on subsequent performance.
• Respiratory system – the respiratory system of the horse is the most susceptible to transport stress. Air quality, inadequate ventilation and the practice of restraining the heads of travelling horses all contribute to the challenge of transportation stress on the respiratory system. The transport vehicle must be well ventilated, use dust free bedding and leave the horse room to lower the head to allow drainage of the airway.
• Orientation – the common theme is that the orientation does not seem to have any affect on the physiological indicators of stress. However several studies noted that horses appeared to maintain balance and suffer fewer impacts when travelling facing away from the direction of travel.

In summary it could be concluded that relatively short trips (under 3 hours) will have little effect on subsequent performance levels. However the management of transport stress in horse transported over longer distances needs to carefully implemented to ensure that the horse is fully recovered before being asked to perform.

References:

Clark, DK, Friend, TH & Dellmeier, G 1993, 'The effect of orientation during trailer transport on heart rate, cortisol and balance in horses', Applied Animal Behaviour Science, vol. 38, no. 3/4, pp. 179-89.

Friend, TH 2000, 'Dehydration, stress, and water consumption of horses during long-distance commercial transport', Journal of Animal Science, vol. 78, no. 10, pp. 2568-80.

Gibbs, AE & Friend, TH 1999, 'Horse preference for orientation during transport and the effect of orientation on balancing ability', Applied Animal Behaviour Science, vol. 63, no. 1, pp. 1-9.

Iacono, CM, Friend, TH, Johnson, RD, Krawczel, PD & Archer, GS 2007, 'A preliminary study on the utilization of an onboard watering system by horses during commercial transport', Applied Animal Behaviour Science, vol. 105, no. 1/3, pp. 227-31.

Marlin, D & Nankervis, K 2002, Equine excercise physiology, Blackwell Science Asia Pty, Carlton, Australia.

Ohmura, H, Hiraga, A, Aida, H, Kuwahara, M, Tsubone, H & Jones, JH 2006, 'Changes in heart rate and heart rate variability in Thoroughbreds during prolonged road transportation', American Journal of Veterinary Research, vol. 67, no. 3, pp. 455-62.

Purswell, JL, Gates, RS, Lawrence, LM, Jacob, JD, Stombaugh, TS & Coleman, RJ 2006, 'Air exchange rate in a horse trailer during road transport', Transactions of the ASABE, vol. 49, no. 1, pp. 193-201.

Shanahan, S 2003, 'Trailer loading stress in horses: behavioral and physiological effects of nonaversive training (TTEAM)', Journal of Applied Animal Welfare Science, vol. 6, no. 4, pp. 263-74.

Smith, BL, Miles, JA, Jones, JH & Willits, NH 1996, 'Influence of suspension, tires, and shock absorbers on vibration in a two-horse trailer', Transactions of the ASAE, vol. 39, no. 3, pp. 1083-92.

Stull, CL & Rodiek, AV 2000, 'Physiological responses of horses to 24 hours of transportation using a commercial van during summer conditions', Journal of Animal Science, vol. 78, no. 6, pp. 1458-66.

---- 2002, 'Effects of cross-tying horses during 24 h of road transport', Equine Veterinary Journal, vol. 34, no. 6, pp. 550-5.

Stull, CL, Spier, SJ, Aldridge, BM, Blanchard, M & Stott, JL 2004, 'Immunological response to long-term transport stress in mature horses and effects of adaptogenic dietary supplementation as an immunomodulator', Equine Veterinary Journal, vol. 36, no. 7, pp. 583-9.

Toscano, MJ & Friend, TH 2001, 'A note on the effects of forward and rear-facing orientations on movement of horses during transport', Applied Animal Behaviour Science, vol. 73, no. 4, pp. 281-7.

Waran, NK, Robertson, V, Cuddeford, D, Kokoszko, A & Marlin, DJ 1996, 'Effects of transporting horses facing either forwards or backwards on their behaviour and heart rate', Veterinary Record, vol. 139, no. 1, pp. 7-11.