Travel related equine pathologies

During transport, a certain number of vital parameters can be monitored to check that the horse is in good health, to make sure the animal is up to being transported and to check that the journey was properly tolerated :

Injury is the most frequent issue during transport. Horses can sustain more or less serious injury (from scratches to fractures). The risk begins when loading, and only ends once the horse is out of the vehicle after transport.

When it cannot be done otherwise, group transport should be done with limited numbers, and with horses who know each other to avoid hierarchical problems for example.

In the case of a fracture, and when transport is necessary to get the horse to a clinic, it is commonly recommended to place the horse so that the injured limb is towards the rear of the vehicle. The horse will therefore travel with his back to the road in the case of a fracture to the forelimb, and the other way round when the hind limb is injured. A thick layer of bedding can be used to limit the vibrations of the vehicle, and the driver should drive extremely smoothly. This type of transport should in any case only be undertaken on veterinary advice.

Another issue which can arise due to transport is laminitis, the main cause being confinement over a number of hours, without having decreased the intake of concentrates prior to traveling. Laminitis can also be triggered by drinking a large quantity of cold water, when the body temperature is slightly increased (usually the case during travel). The risk of laminitis is also exaccerbated by stress to the hoof due to long periods traveling, hence the need for breaks in a long journey to allow the horse to rest his musculoskeletal system.

To sum up, here are some strong recommendations :

• Have a break of 20 minutes every 4 hours to offer a bucket of water, it can be flavored or the hay can be dampened if necessary;
• Make sure that he horse does not drink too quickly when water is provided;
• Provide long fibers such as hay before and during transport so that the stomach is not empty. Concentrates should be avoided. Feed which is too rich can strongly increase the risk of laminitis ;
• Prepare the sensitive or stressed horse by feeding yeast supplements before the journey.

Since a transport means is necessarily a confined space, the quality of the air can decrease and humidity increases. It has been proved that horses prefer the cold to humidity, therefore keep the air vents in the vehicle open, as far as the outside climatic conditions will allow.

If these factors are not taken into account, the poor quality of the air can affect the respiratory tract immune system, and the risk of lung inflammation increases. The trachea is particularly sensitive, especially in horses subject to respiratory problems (Stull et al., 2002). This is due to the horse’s position during travel. The head is higher than usual, which restricts poll movement and obstructs part of the respiratry tract (Oikawa et al., 1995). If the journey continues in poor conditions, the inflammation of the lungs could turn into pneumonia. These breathing ailments are commonly known as « travel fever », and symptoms range from the horse having a temperature intermittently, to pleuropneumonia  (Stull et al., 2002).

These afflictions do not necessarily lead to coughing. But on the other hand the horse may develop allergies due to airborne dust particles when traveling. These allergies can lead to chronic coughs, previously known as emphysema. The risks can be minimized by keeping the vehicle as dust free as possible.

Between journeys, cleaning the vehicle will help enourmously in the prevention of respiratory disease. The use of a disinfectant as mentioned in the regulations will eliminate spores, fungii, and the composite allergens in dust. The vehicle should however first be cleaned with water as disinfectants are inactive when in presence of organic matter (such as droppings for example).

Thus, the ventilation, the quality of forage and bedding used are the parameters to keep an eye on :

• Prefer vehicles with adjustable ventilation, or even with dynamic ventilation systems;
• Prefer shavings as bedding rather than straw bedding;
• Use good quality hay, and as dust-free as possible;
• Clean and disinfect the vehicle regularly between journeys.

During transport, the proximity between horses and the confinement will increase the risk of transmission of contagious diseases. Equine influenza, and strangles can thus be transmitted during transport. It is therefore essential not to travel a sick horse with other horses whenever possible.

The first thing to avoid is to transport sick horses or horses during an incubation period. In doubt, carry out an examination of the horse and if there is even the slightest doubt consult the vet before transporting.

If transport cannot be avoided for veterinarian reasons, the sick horse should travel alone. After which the vehicle should be carefully disinfected as some viruses such as  Rhodococcus equi can remain present on the walls and dividers of the horse box.