Acid Detergent Fibre (ADF):

The cell wall portion of forage which includes cellulose and lignin. As ADF increases, the digestibility of forage decreases.

Alfalfa (also known as Lucerne):

A perennial flowering legume related to the pea family. Alfalfa is an excellent source of fibre that is naturally high in protein and calcium.

Amino Acids:

The building blocks of protein. There are 21 amino acids in total, 9 of which are termed as ‘essential’ because they cannot be synthesised by the body and must therefore be provided by the diet.


A molecule which inhibits the oxidation of other molecules (iron turning rusty or an apple going brown once it has been sliced are both examples of oxidation). Oxidation can produce ‘free radicals’ which may damage cells, tissue and potentially DNA. In humans oxidative damage has been seen to contribute to cancer, heart disease and even the ageing process. Examples of dietary antioxidants include vitamin E, vitamin C and selenium. 


The term used by nutritionists to define the amount of feed a horse or pony requires per day. Depending on the individual’s age, workload and condition, total daily appetite (feed and forage) typically ranges from 1.5 to 2.5% of bodyweight dry matter per day i.e. 7.5-12.5kg per day for a 500kg horse. 


Although this may sound like something you find in your fire place, it actually represents the mineral content of your feed. 


A water soluble B-vitamin synthesised by microbes in the hindgut. Although biotin deficiency has not been reported in horses, feeding biotin at a high level has been seen to improve hoof health and growth in some studies. Biotin is also involved in fatty acid synthesis, gluconeogenesis (a metabolic process in which glucose is produced from non-carbohydrate substrates), amino acid metabolism and other metabolic pathways.

Body Condition Scoring:

A method of practically assessing the horse or pony’s level of fat covering across several areas of the body where fat is normally laid down using a numerical grading system. Depending on the scale used, the horse/ pony is given a body condition score (BCS) of between 0 and 5 or 1 and 9.


The hard outer layer of wheat grains produced as a by-product of wheat milling,  traditionally fed to horses in the form of a ‘bran mash’. Bran is unsuitably high in calcium and low in phosphorus meaning it will unbalance the diet unless fed alongside a broad spectrum vitamin and mineral supplement or balancer. The infrequent feeding of bran or bran mashes should be avoided as this rapid dietary change upsets the microbial population of the hindgut.


Water soluble vitamins synthesised by hindgut microbes. B-vitamins include biotin, folic acid, niacin, thiamine (B1) and riboflavin (B2).


The first section of the large intestine or ‘hindgut’. The caecum is often referred to as a ‘blind-ended sack’ as it shares the same entrance and exit site. Fibre is fermented by microbes in the caecum (to produce volatile fatty acids) along with any undigested starch and sugar overflowing from the small intestine. 


A macro mineral which plays a key role supporting bone health. In fact, 99% of calcium in the body is stored in bone. The ratio of calcium: phosphorus in the diet should be maintained at 1.5-2:1. High levels of phosphorus decrease calcium absorption, resulting in deficiency. Consequently calcium is drawn from the bones which in severe cases may cause them to weaken.


In the simplest sense, colic refers to abdominal pain. Generally colic can be classified as one of the following types: impaction (a blockage in the intestine), tympanitic/ gaseous (a build-up of gas in the intestine), spasmodic (increased intestinal contractions) or sand colic (caused by the ingestion of sand resulting in inflammation or a blockage).


A micro mineral or ‘trace element’ involved in numerous cell functions including the formation of haemoglobin, keratin synthesis and bone formation. 


A hormonal disorder affecting the pituitary gland also known as ‘PPID’. Clinical signs include a failure or later shedding of winter coat which may be long, thick, wavy and curly, a ‘pot-bellied’ appearance, excessive sweating, increased drinking and urination, lethargy, loss of muscle tone, abnormal fat distribution (particularly above the eyes, along the crest of the neck and above the tail), chronic or recurrent laminitis and delayed wound healing.


A term used to describe a horse or pony that has been diagnosed with Cushing’s syndrome (see PPID).

Digestible Energy: 

A measurement of the energy available from feed after the production of faeces. On feed bags you will see the level of energy listed as ‘mega-joules of digestible energy per kilogram’ or ‘MJ DE/ kg’

Dry Matter (DM):

The material remaining after all of the water has been removed. The dry matter content of different feed stuffs varies. For example, hay contains approximately 85% DM whilst haylage typically contains 55-70% DM.


Mineral salts which conduct an electric charge when dissolved in water. Electrolytes control the movement of water around the body and maintain fluid balance. They are also involved in numerous cell functions including muscle contractions and the transmission of nerve impulses. When horses sweat they lose electrolytes, the main ones being sodium, potassium and chloride. In horses sweating regularly, some of these losses should be replaced either by feeding a specialist electrolyte supplement or salt (a combination of table salt and Lo Salt may be required).

Equine Rhabdomyolysis (ERS):

A condition that causes the muscles running over the hind quarters to tighten and cramp up. It may also be referred to as tying up, set-fast, Azoturia or Monday morning disease.


A structural carbohydrate essential for maintaining digestive health. Fibre also provides a valuable source of energy.


Long chains of fructose often linked to sucrose. Fructans are the storage form of sugar (energy) in plants. Although the exact link is unclear, it is thought that fructans play a role in triggering pasture associated with laminitis. 

Fructo-oligosaccharide (FOS):

A soluble fibre that acts as a prebiotic in the gut by supplying a preferred energy substrate (food) for "good" bacteria.

Gastric ulcers (also known as Equine Gastric Ulcer Syndrome or ‘EGUS’): 

Lesions caused by the prolonged exposure of the gastric mucosa (stomach lining) to gastric acid.


An ‘amino sugar’ commonly fed to support joint health. Glucosamine is a chondroprotective agent and is thought to support proteoglycan synthesis and reduce cartilage degradation.


A monosaccharide or ‘simple sugar’. Glucose is the primary source of energy used by the body – including the brain!


Grass that has been cut, dried (in the field) and baled. Meadow hay contains approximately 85% dry matter and 15% moisture.


Grass that has been cut, dried to approximately 25-45% moisture, baled and then shrink wrapped in plastic to prevent mould development.


A term used to refer to the horse/ pony’s large intestine which comprises of the caecum, large colon and small colon.

Hyaluronic Acid (HA):

A Glycosaminoglycan (a type of protein connected to carbohydrate found in connective tissue which is useful as a lubricant and a shock absorber) found in synovial joint fluid. It is also an important component of cartilage. HA is commonly included in joint supplements.


A hormone produced by beta cells in the pancreas to control blood glucose levels. Insulin acts a chemical messenger which helps cells to use or store glucose.’

Insulin dysregulation:

A collective term used to describe high circulating blood insulin levels and/or an increased insulin response to a starch/sugar load and/ or insulin resistance. 


A micro mineral (meaning it is needed in small amounts) essential for the synthesis of the thyroid hormones thyroxine and tri-iodothyronine.


A micro mineral’ or ‘trace element,’ meaning that it is required in smaller amounts by the horse. Its primary function lies in oxygen transport and consequently, approximately 60% of the iron in the horse’s body is in haemoglobin – the protein which carries oxygen and gives blood its red colour.

International Unit:

The unit used to measure some vitamins including vitamin E.


The second or 'middle' section of the small intestine. The small intestine comprises of three sections; the duodenum (the first section linked to the stomach), the jejunum and the ileum which joins the caecum.


In its simplest sense, laminitis is inflammation of the laminae resulting in pain and lameness. Laminitis is likely to be the result of a complex cascade of events which may involve multiple systems within the body.


The soft tissue that attaches the pedal bone to the hoof wall.


An essential amino acid meaning it cannot be synthesised by the body and must therefore be provided by the diet. Lysine is the ‘first limiting’ amino acid which means the extent to which other amino acids can be utilised is dependent on lysine intake.

Lucerne (also known as Alfalfa): 

A perennial flowering legume related to the pea family. Alfalfa is an excellent source of fibre that is naturally high in protein and calcium.


A macro mineral involved in hundreds of enzyme reactions including the generation of cellular energy, the transmission of nerve impulses and muscle contractions. Approximately 60% of magnesium in the body is stored in the skeleton with the remainder found in muscles, soft tissues and in bodily fluids where it helps to maintain fluid balance. Magnesium deficiencies are rare but can be associated with impaired muscle and nerve function. Anecdotally, magnesium is known for its calming properties.  

Macro minerals:

Minerals that are required in relatively large amounts (grams per day) including calcium, phosphorus and magnesium


A sulfur containing amino acid often included in hoof supplements.

Micro minerals: 

Minerals that are required in relatively small amounts (milligrams/ day) including copper, zinc and selenium. Micro minerals are also referred to as ‘trace elements’.

Manna-oligosaccharide (MOS):

The cell wall of yeast often used as a ‘prebiotic’. MOS may help to support gut and immune health by reducing the colonisation of ‘bad bacteria’ in the gut.


A by-product of the sugar refining process from either sugar beet or cane molasses. Molasses is added to compound feeds to increase palatability and to help bind other raw materials together when making cubes or pellets.

Methyl Sulphonyl Methane (MSM): 

A sulphur rich ingredient commonly used in joint supplements.

Neutral Detergent Fibre (NDF):

A measure of the total plant cell wall comprising of ADF and hemicellulose. NDF is an indicator of total fibre content.

Non-Structural Carbohydrate:

The sum of starch, sugar and fructan.


A by-product of oat milling often used to provide a source of slowly fermentable fibre in compound feed


A source of energy digested by enzymes in the small instance. Oil is approximately 2.5 times higher in energy compared to cereals and starch free, making it a sympathetic alternative to cereal starch for horses prone to excitability or clinical conditions such tying up.

Pituitary Pars Intermedia Dysfunction (PPID):

A hormonal disorder affecting the pituitary gland also known as ‘Cushing’s syndrome'. Clinical signs include a failure or later shedding of winter coat which may be long, thick, wavy and curly, a ‘pot-bellied’ appearance, excessive sweating, increased drinking and urination, lethargy, loss of muscle tone, abnormal fat distribution (particularly above the eyes, along the crest of the neck and above the tail), chronic or recurrent laminitis and delayed wound healing.


A macro-mineral found mainly within skeletal muscle. Along with sodium and chloride, potassium is an important electrolyte which plays a key role in maintaining water balance.


A live organism (either a yeast or bacteria) that is introduced to the gut to help promote beneficial bacteria. Equine probiotic supplements in the UK contain live yeast as live bacteria are not licenced for use in horses in the EU.


A fermentable food source that is utilised by beneficial bacteria in the gut helping to support a healthy microbial population. FOS is an example of a prebiotic.

Polysaccharide Storage Myopathy (PSSM):

A form or tying up related to a defect in carbohydrate utilisation and/or storage in the muscle. PSSM Commonly affects Quarter Horses and their crosses (Paints & Appaloosas), Draughts, Warmbloods and Morgans although cases in Anglo-Arabs, Andalusians and Cobs have also been reported in the UK.


A macro-mineral and major component of bone thus making it essential for bone strength. Phosphorus is also involved in energy metabolism and microbial digestion.


A term used to describe partially chewed food being dropped from the mouth. Quidding commonly occurs in older horses as result of excess wear on their molar teeth.

Riboflavin (vitamin B2): 

A water soluble vitamin involved in energy metabolism. Like other B-vitamins, Riboflavin is synthesised by hindgut microbes.

Rice bran: 

A by-product of rice milling often used in the formulation of compound feeds for its naturally high oil content.


A micro-mineral or ‘trace element’ which works closely with vitamin E within the body’s antioxidant defence system.  Selenium is required in very small amounts in the diet and can be toxic if fed at high levels.

Soya bean meal:

Soya beans which through the process of cracking, heating and flaking become de-hulled to produce soya bean meal. Soya bean meal is naturally high in protein and amino acids.

Soya hulls:

A by-product from the de-hulling of soya beans. Soya hulls are an excellent source of high digestible/ rapidly fermentable fibre.


A form of non-structural carbohydrate utilised as an energy source. Cereal grains are high in starch and should therefore be avoided for ponies and native breeds, laminitics and horses prone to excitability. Horses prone to colic, tying up and gastric ulcers also need a low/ controlled starch diet.


Carbohydrates that can categorised according to the number of units they contain. Monosaccharides or ‘simple sugars’ consist of just one unit and include glucose, fructose and galactose. Disaccharides consist of two units and include sucrose (the sugar you in your tea), lactose (milk sugar) and maltose (which makes Maltesers taste so good!).

Sugar beet:

A root vegetable. The sugar beet fed to horses is a by-product of sugar beet processing which produces the sugar (sucrose) we put in our tea! Although sugar beet is high in energy (calories) and fibre, the increase in volume after soaking makes it easy to over estimate how much you are feeding.


An essential amino acid. It is thought to be the second limiting amino acid in the horse, especially for growth, which means it is important for determining the overall rate of protein synthesis.

Thiamine (vitamin B1):

A water soluble vitamin essential for energy metabolism. It also plays a key role in nerve, muscle and heart function. Like other B-vitamins, Thiamine is synthesised by hindgut microbes..

Tying up:

Also known as Equine Rhabdomyolysis (ERS). A condition that causes the muscles running over the hind quarters to tighten and cramp up. It may also be referred to as set-fast, Azoturia or Monday morning disease.

Volatile Fatty Acids (VFA’s):

The end product of fibre fermentation produced by the microbes in the caecum and large colon. VFA’s are absorbed through the gut wall and utilised as an energy source.

Vitamin A (retinol):

A fat soluble vitamin essential for immunity, cell differentiation and maintenance of the respiratory and digestive system, as well as hoof quality, growth, reproduction and vision. 

Vitamin B12:

A water soluble vitamin required for effective energy metabolism. Vitamin B12 is not naturally found in food and can only be synthesised by microbes in the hindgut.

Vitamin C:

A water soluble vitamin and natural antioxidant which plays an important role in supporting respiratory and immune health. Vitamin C is synthesised from glucose in the liver and consequently healthy horses often do not require additional vitamin C in their diet. However, supplementary vitamin C may be helpful for those under stress, in heavy exercise or during illness. 

Vitamin D:

A fat soluble vitamin involved in calcium and phosphorus metabolism thus making it important for healthy bones and teeth. Vitamin D is sometimes referred to as the ‘sunshine vitamin’ because it is synthesised in the presence of UV light from a form of cholesterol in the skin. Consequently horses that are stabled or rugged for long periods may need additional vitamin D.

Vitamin E:

A fat soluble vitamin which plays a key role in supporting immune and muscle health. Vitamin E is considered to be the most important antioxidant and works alongside vitamin C and selenium. 

Vitamin K:

A fat soluble vitamin essential for blood clotting; It also plays a role in bone health.

Water Soluble Carbohydrate (WSC): 

Carbohydrates that are soluble in water including the approximate sum of sugar and fructan.


A by-product of wheat milling often used as a source of slowly fermentable fibre in compound feed.


Unicellular (single celled) fungi used in bread making! For horses, live yeast can provide beneficial bacteria whilst inactive yeast can be used to provide a valuable source of B vitamins.  


A micro-mineral or ‘trace element’ which plays a major role in many enzymes throughout the body and is important for bone, immune, skin and hoof health.