The immune system: everything you need to know

The immune system: everything you need to know

The body’s immune system is what protects it from germs, viruses, and bacteria. The stronger the immune system, the less likely the horse will fall ill. It’s also responsible for recovery after physical exertion. Although the immune system is invisible, it plays an important role in the horse’s well-being. The immune system is constantly working to quickly fight off threats to the body.

An army of white blood cells

The skin is an important protective shield against invaders and in many cases prevents them from entering the body. However, they can find their way into the airways or mucous membranes through openings in the skin (wounds). Just like the human body, the equine body has an entire “army” of white blood cells standing at the ready. These white blood cells attack anything that the body doesn’t “know”. Amongst the most important are macrophages, which recognise bacteria as invaders and then suck them up. The bacteria are slowly broken down into smaller components and the anti-inflammatory substance cytokine is produced. This substance alerts all other cells and also triggers other white blood cells to get to work at eliminating the invading bacteria. If the germs are stronger than the immune system, the army of white blood cells will be overcome by the virus. The horse will fall ill and come down with a fever.

Physical and mental health

The immune system determines a horse’s physical health. An important link to this system is the intestinal tract. A healthy gut is the first step to equine health. The horse’s physical defences are determined by a system made up of several bodily elements:  the thymus, gut, lymphatic system, white blood cells, bone marrow, antibodies, mucous membranes, skin, spleen, and liver. These elements interact to form the immune system, with everything managed by the thymus.

A horse’s physical natural defences are not the only influences on its resistance to pathogens: its mental health also plays an important role. Consider stress, which can have a huge impact on a horse’s immune system. Always keep an eye on your horse’s mental condition. Ensure adequate turnout and social contact and avoid conditions that lead to boredom and frustration. Your horse’s natural defences depend on its physical and psychological health.

Immune system is physical and mental health

Gut flora & the immune system

The gut is the largest barrier between your horse’s body and the external environment. The gut membrane comes in contact with everything that the horse eats and drinks. The intestinal wall is extremely thin despite this important task. If the horse comes in contact with harmful substances, these can be potentially lethal. This is where the immune system comes in – the army that fights off contaminants and keeps the body from harm.

The development of a healthy digestive system begins shortly after birth. When the foal drinks the mare’s colostrum, the first antibodies enter the blood and the first bacteria enter the large intestine, including the bacteria that settle there, called bacterial flora or microflora. These enter the intestine through the mother’s milk or when the foal ingests horse faeces. The gut’s immune system must first recognise this microflora so that it can later distinguish clearly between pathogenic and non-pathogenic bacteria in the gut.

When bacteria first enter the gut, they are regarded as substances foreign to the body, provoking a response from the immune system. However, when the host recognises that these bacteria are not pathogens, there is no longer a reaction. Bacteria and horse can thus cooperate in their mutual need of each other for survival. The horse is built to digest fibre all day, but plant material that’s harder to digest needs help from microflora. The microflora converts the fibre from the plants into fatty acids and B vitamins, which provide the horse with energy.

The gut flora plays a crucial role in the regulation of the immune system. It protects the body from harmful outside factors. A healthy gut microbiome is therefore essential for maintaining good health and optimum performance. Fibre delivers good bacteria and a good immune system begins with good fibre in the feed. Eating roughage also meets psychological needs. A horse is naturally accustomed to eating for up to 16 hours a day.

The gut flora is important

Recommendation from our feed experts: fibre for a strong immune system

A good immune system needs fibre. Cavalor makes several products with emphasis on fibre. We’ve included three of them below. Also of special note is the new formula for Cavalor Resist + Vit C. Resist + Vit C strengthens the natural defences of horses that are often on the road or are recovering from illness.


Cavalor FiberForce is an ultra-high-fibre herbal müsli enriched with pre and probiotics to support gut flora and general gut health. Cavalor FiberForce boasts a unique blend of high-quality, easily digestible fibre feeds. Its added herbs provide additional nutrients to the skin and coat. With minimal starch and sugar – ideal for horses with delicate stomachs or susceptibilities to metabolic illnesses.

Fiberforce Gastro

Cavalor Fiberforce Gastro is specially developed for horses that are prone to stomach irritations and stomach ulcers. It is an ultra-high-fibre herbal müsli with minimal starch and sugar and contains lucerne, Timothy stalks, teff grass pellets, and beet pulp. Fiberforce Gastro is also enriched with acid buffers that neutralise excess stomach acid and protect the stomach wall from irritations. It also contains fenugreek, is especially tasty, and stimulates the appetite.

Fiber Beet Mash

Cavalor Fiber Beet Mash is rich in high-quality fibre. It contains flaked beet pulp and NO oats. A delicious treat for all horses. Also suitable for seniors and horses with dental issues.

Resist + Vit C > new formula!
Cavalor Resist + Vit C supports your horse’s natural defences and immune system, making your horse less susceptible to infections and providing protection from pathogens. Our Cavalor Resist + Vit C has a new formula! We’ve now supplemented the herbs in our old formula with tee tree oil, lemon eucalyptus oil, and lemongrass oil. These essential oils take strain off the immune system by supporting the airways, blood circulation, and lymphatic system.


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