As therapists we learn about the many different systems in the equine body, but a lot of the focus is on bony landmarks, superficial and deep muscles, and movement.
It’s exciting to also understand what happens to the horse beneath the skin as this makes us truly appreciate what the body does to stay alive. Good quality courses offer a section of education explaining the other systems of the body as well. The lymphatic system is a system that is not well understood at times, and there is limited education in Australia and globally that explains what the system does, how it works, and why as owners and therapists we can benefit from understanding the basics of the lymphatic system and how to provide support.
The lymphatic system is one body system that is often not thought about until it is already showing signs of distress. Most times, until there are signs of illness and swelling, we assume the lymphatic system is not being impacted. Horses have poor venous return making their current husbandry techniques of stall rest, smaller paddocks and long float rides factors that can have a significant impact on the lymphatic system. Recovery times for horses may also become impacted as lymph movement is at a reduced capacity to transport new white blood cells (lymphocytes), proteins, and fats through the body.
Unlike other systems in the body, the lymphatic system is not considered a circuit. It is open-ended and runs parallel to the circulatory system. Lymph is returned to the blood system from the left and right subclavian veins. The anatomical design of the lymphatic system of the horse creates ‘bottlenecks’ that are susceptible to becoming overloaded. Without the removal of this excess fluid, it would build up around the tissues (edema). The lymph (fluid of the lymphatic system) can only flow one way.
Lymph fluid contains:
- Red and white blood cells
- Lymphocytes (B and T cells)
- Foreign invaders (viruses, bacteria, fungus, parasites)
- Fat (intestinal lymph)
- Dead cells
- Cancer cells
- Dead cells
The lymphatic system does not have a pump, it needs:
- Contraction of skeletal muscle – this moves the lymph forward in the system via the lymphatic vessels.
- Negative pressure – ‘suction’ creates the force to push the lymph up.
- Breathing – (which we all know is important at all times) creates another ‘pump’ with the contracting and relaxing of the diaphragm
The lymphatic system is also vital for immunity. As lymph moves through the system, the nodes remove and destroy what can cause harm to the body. If this does not happen the body becomes more prone to illness.
The lymphatic system is divided between superficial and deep. Superficial lymphatic vessels are closer to the skin surface. When grooming or applying manual lymphatic drainage, stimulation of the hair lightly pulls the pre-collectors of the lymphatic system beginning the flow-on effect to promote the movement of lymph.
Movement and grooming support the lymphatic system by helping provide stimulation to the vessels and support the movement of lymph through the lymphatic vessels without creating ‘pooling’ in the sensitive vessels. Assisting the lymph through the body helps with recovery, promotes the movement of lymph, and helps horses feel relaxed.
Lymphatic drainage is not suitable for horses that have conditions such as fever, cardia edema, congestive heart failure, kidney issue, or acute infection. Discussions with a vet is highly recommended before treatment begins.
Correct lymphatic techniques include stimulation of the major lymph nodes and follow the anatomical design (also referred to at times as a watershed) of the lymphatic system. The lymphatic system is sensitive, as horses have more elastic fibers than humans and respond to lymphatic drainage better than humans.
The lymph system is exciting to learn about. It is important for owners and therapists to have resources available to them when horses begin to show sign of distress in the lymphatic system.
As a therapist I am excited to share my passion about the lymphatic system. This is not possible with out the support of owners and therapists sharing their stories about equine lymphatic conditions.
Please email email@example.com to share your experience.
This is a very brief overview of the lymphatic system. This is not veterinary advice, if you are concerned your horse is showing any signs of illness, please contact your vet.