Thunderbrook Base Mix

A concentrated cereal free, complete and balanced feed containing all the main essential vitamins and minerals, together with pre and probiotics. Suitable for horses of all disciplines, veterans and youngstock.

  • Low feeding rate
  • Pre and Probiotics
  • Full NRC daily guidelines for Vit and Mins


Please call to arrange collection – 0114 288 2465
Collection / local delivery only within a 10-mile radius of S75 3HP.



A concentrated balanced base feed. Ideal for all horses of all disciplines. Contains the essential amino acids, essential fatty acids, nucleic acids, natural vitamins, minerals, over 100 anti-oxidants, metabolic cofactors and other micro-nutrients in a form both bioavailable and clean. One 15kg sack contains sufficient feed for a horse in light work for 30 days.

Why choose ‘Equine Pure Essentials Base Mix’?

  • No fillers, binders, pelleting agents, preservatives or chemically synthesised micro-nutrients are included.
  • All Ingredients have been carefully sourced to avoid fertiliser, pesticide, herbicide and other chemical treatments, preservatives, mould inhibitors, etc. wherever possible and whilst trying to keep costs low.
  • All Ingredients have been carefully processed to minimise denaturation of the essential macro and micro nutrients.
  • Contains No wheat, wheatfeed, oatfeed, soya, legumes, sugar beet, molasses, alfalfa, soya oil, corn oil, mixed vegetable oil or waste by-products from human oat or wheat food milling and production.
  • Superior Ratio of beneficial omega-3 polyunsaturates, high quality oil, high quality protein, extremely low sugar and starch feed.
  • Added prebiotics, probiotics, fruits, herbs and botanicals in generous amounts, providing functional foods to nutritionally support a healthy gut environment.
  • No need to add other supplements such as probiotics, magnesium calmers, oils, etc

Composition: Stabilised and ground whole linseed, naturally stabilised rice bran, natural fractionated yeast extract, proprietary blend of herbs (fruits, herbs and botanicals), limestone flour, magnesium carbonate, Bioplex minerals, Lysine, Yea-Sacc, Bio-Mos, Natural vitamin E, chelated magnesium, chelated calcium, chelated zinc, chelated copper, chelated selenium, organic extra virgin sesame seed oil, natural vitamin A and D3.

Analysis: Oil (23.25%), Protein (22%), Starch (10%), Sugar (2.8%), Fibre (5.75%), Ash (14%)  DE=15.5MJ/kg

Comparison of Base Mix with NRC guidelines for a 500kg healthy adult horse at maintenance.
The National Research Council (NRC) guidelines are the industry recognised standard for recommended daily rates of nutrients for horses. All grazing, forage and browse will contain various amounts of vitamins, minerals and other essential nutrients, but very often due to modern farming techniques, pasture management, etc, many of these nutrients can be deficient. When formulating a balancer (to ‘balance’ against this forage), Thunderbrook take into account the levels of such nutrients in a typical UK forage.

Some nutrients are typically in short supply and are important additions to a balancer (such as copper, zinc, magnesium and selenium) whereas others are often supplied in abundance in typical forage and to over supplement could be detrimental (for example iron and manganese). Hence, it would not be sensible to formulate a balancer that meets 100% of the NRC nutrient requirements just from the balancer alone, as the nutrients provided from forage which makes up the bulk of the horse’s diet also need to be taken into account.

Base Mix meets the full daily requirement for the main vitamins and minerals, according to NRC guidelines, when fed at the recommended daily rate alongside forage. Vitamins and minerals are supplied in Base Mix through those naturally sourced from the ingredients (linseed, nutritional yeast etc) and from those added separately (labelled and declared as ‘additives’ under EU legislation). The additives have to be declared by law, but the nutrients supplied through the natural ingredients do not have to be declared on the label. This is simply because they are harder to quantify as there is natural variation from batch to batch. The table below gives more information than that what is legally required on a feed sack label. It includes to the best of our ability the nutrients provided from the ingredients as well as the separately added nutrients.

The main vitamins and minerals to balance against average UK forage are highlighted in red in the table below. These are the key vitamins and minerals (copper, zinc, magnesium and selenium) that can be in short supply in average UK forage.

Some minerals are not added to Base Mix (such as iron and manganese) as they are rarely ever found to be lacking in the horse’s forage and excess supplementation is considered potentially harmful. For example, the 400mg of iron per day according to NRC guidelines in the table below will be obtained from eating just one or two kilos of average hay. The levels of iron and manganese in Base Mix are from the natural ingredients only (linseed, nutritional yeast, etc). Other minerals such as selenium are toxic when fed at higher levels. As selenium levels can be low in forage, but rarely ever completely lacking, we include selenium at slightly under the NRC level to compensate, and ensure we avoid toxicity problems.

Some balancers contain copper and zinc at many times the NRC recommended daily rates. Base Mix is formulated to meet the NRC requirements, but not at multiple concentrations higher. This is for two reasons. Firstly because the NRC guidelines are the most researched data available. Claims that higher levels of copper and zinc are required are not backed up with robust scientific research and peer reviewed papers. Secondly because the European Legislation on feed additives has maximum limits set for minerals such as copper and zinc, to avoid toxicity. Adding copper and zinc in Base Mix at multiple concentrations higher to the NRC guidelines could result in toxicity if the horse’s forage is already high in copper and zinc (and occasionally this can be the case).

Calcium, phosphorus and potassium are always found in forage and a horse’s diet is rarely short of these minerals, so again they are included at levels to balance average UK forage, and each other. Similarly, sulphur is found in grass (average 0.2%). A 500kg horse eating 10kg dry weight of grass will consume 20g of sulphur which is higher than the NRC guideline figure, and hence we do not include additional sulphur in Base Mix.

Sodium and chloride are the constituents of basic ‘salt’. We do not include salt in Base Mix as this would compromise the shelf life of the product (and it is also a cheap ingredient that can easily be added separately). Cobalt is not included as there are legislative requirements regarding the addition of cobalt to animal feeds. The level of cobalt quoted in the table for Base Mix is that found from the natural ingredients. We add Vitamin B12 instead (which is a vitamin made from cobalt).

If you have any questions about our nutritional analysis, please feel free to call our nutritional helpline to discuss further.


Feeding instructions: See feeding guide below for amounts. Add a handful or two of our Healthy Herbal Chaff or Muesli to provide texture and aid chewing. Dampen before feeding. Maximum daily rate is best split between multiple feeds per day. For best results avoid feeding with processed chaffs, mixes, pellets or other feeds containing straw, wheatfeed, oatfeed, soya, soya hulls (as these are the main ingredients with potentially high pesticide and mycotoxin residues), and those containing molasses, preservatives, etc. Instead, feed with ad lib hay, and unprocessed straights such as dried grass, freshly milled stoneground Organic Bran, Organic Mature Oats for germinating, etc. Provide plenty of fresh water and access to a natural mineral salt lick as Base Mix does not contain added salt (average horse at maintenance requires approx. 20g per day). Base Mix fed at 100g per 100kg bodyweight per day provides the full daily ration of the main vitamins, minerals and trace elements, prebiotics, probiotics, essential amino acids and essential fatty acids. Always introduce a new feed slowly. Add just one pinch of Base Mix to your horse’s first feed and work up gradually over 4 or 5 days to the full amount (see below).

Feeding Guide:
Healthy adult horses at maintenance on poor forage (restricted grazing, grazing muzzle, high fibre hay, soaked hay, straw, etc), or poor doers = 100g per 100kg bodyweight per day.

Healthy adult horses at maintenance on good forage (fresh spring and summer grass, good quality hay, etc) or good doers = 50g per 100kg bodyweight per day.

Youngstock, Brood Mares, Competition Horses in heavy work or Convalescing Horses (eg those requiring weight gain) = 100g to 150g per 100kg bodyweight per day.

With a maximum feeding rate of 150g per 100kg bodyweight per day.

Precautionary guidance for horses with special dietary requirements
Some horses with compromised digestive systems may require vitamins and minerals supplied at higher than the daily recommended rate, due to the inefficiencies caused by malabsorption or dysbiosis. For horses showing lethargy, poor hoof quality or lack of intensity of coat colour, even when fed Base Mix at the full recommended rate, we suggest also feeding ‘Gut-Restore’ together with ‘Liquid Gold’.

Note for Metabolically challenged horses
Base Mix is 10% starch and 2.8% sugar, but is only fed in small quantities per meal.

A feed of 250g of Base Mix at the 10% starch contains just 25g of starch in that meal. In contrast, a ‘low starch’ feed at just 5% starch, but with a recommended feeding rate of 1KG, will contain 50g of starch in that meal.

Hence, remember to multiply the feeding rate alongside the percentage composition, in order to calculate the actual amount of starch in the feed bowl, as this is what affects the insulin levels of metabolically challenged horses.