Nutritional Challenges of Springtime

By: Dr Catherine Dunnett BSc, PhD, R.Nutr

Moving Towards the Competition Season

At this time of year we are optimistically looking forward to Spring, hoping we have left the worst of the winter weather behind us. We are all looking forward to riding more as the weather improves and the professionals and other active competitors are busy pushing forward with training as this years competition season rapidly approaches.  This period brings with it numerous potential problems some of which can be related to diet and management.  Lameness may become apparent as exercise regimes become more intense and horses can sometimes exhibit raised muscle enzymes, or acute episodes of tying up.  Respiratory issues can also sometimes occur, as we move out of winter and some horses may be feeling a little too well, displaying over exuberant behaviour.  Feed and management go hand in hand at this time of the year to reduce the liklihood of some of these early season potential problems.

Overfed horses can become fat or too excitable

During early schooling and training the emphasis from a nutritional point of view should be on adequate but not excessive energy intake.  Although it remains important that a balanced diet is always fed in terms of vitamins, minerals and amino acids from quality protein sources.  An overfed horse, depending on type and temprament, can become either fat and stuffy and so difficult to slim down for competition, or in contrast badly behaved and excitable.  Over exitable horses, as the result of too much feed to early in the season, are a nuisance and can increase the risk of injury to themselves or their rider.

Excitability is less likely to happen when forage remains the focus of the diet.  Good quality hay or haylage fed in increased amounts as more work increases, will not only help to reduce the reliance on concentrate feed, but may also lessen the possibility of undesirable gastric ulceration.

Dr Green can be a blessing and a curse

Access to pasture and grass availability starts to increases as we move into Spring.  This can bring many benefits and a lot of horses will bloom, filling out and losing their angular appearance in response to more grass.  Others may become unruly and excitable as the new grass, rich in available nutrients including sugars, is redily consumed.  It is important to respond to this increase in energy from pasture by reducing any concentrate feed accordingly, and then adjusting again as work rate increases and body condition dictates.  If stabled overnight, maintaining a good intake of forage is crucial as this helps to maintain healthy digestive function and will offer some natural protection against digestive upsets during this time of dietary change.

If you have a horse or pony that is prone to laminitis, managing the increased availability of pasture is important and of course ensuring that they are not overweight moving into Spring.  Thrifty types have a huge capacity for eating grass within a short period of time and so restricting grass access by area is a much better way of managing the problem.  Using moveable roundpens, and strip grazing using electric fencing is a much more effective and practical way to achieve this.

Concentrate Conundrum

There are many concentrate feeds manufactured specifically for horses in light exercise, which are suitable for this early stage of work.  These are generally lower in energy than competition feeds, which is appropriate, but not all ensure an adequate intake of quality protein, or are suitably concentrated enough to provide an appropriate level of vitamins and minerals.

Protein provides the building blocks for life and specifically is needed to supply amino acids for tissue growth and repair.  Certain amino acids such as leucine are believed to be important to support the repair processes in muscle, by stimulating muscle protein synthesis.  Whilst all ingredients will provide some protein, the type of ingredient affects both the digestibility (how easily the amino acids are released by digestion) and the quality, which refers to the amino acid makeup of the protein source compared to the horses’ true requirements.  Ingredients like soya are historically regarded as the better quality protein sources in horse feed and are known to be highly digestible.  Oilseed and Cereal protein is generally regarded as being superior to cereal bi-products and forages.  With respect to forages, alfalfa or lucerne represents one of the better sources of quality digestible protein.  Clearly there is a balance to be achieved between different ingredients.

Choice of concentrate feed should depend on the amount fed to maintain condition.  During early work, many horses will not require the standard minimum recommended amount of a traditional coarse mix or cube, which is typically 3-4kg for a 500kg horse.  In this scenario, a feed formulated to be fed at a lower level of intake through concentration of vitamins and minerals and a higher percentage protein is a sensible route.

Some consideration should also be given to the main energy source in your concentrate feed.  Some horses react badly to a high intake of starch from concentrates and may experience issues with excitability, digestive upset or muscle problems such as tying up in early work.  Feeds that are high in digestible fibre and oil, with less emphasis on cereal starch are more appropriate in this scenario.

Muscle damage

Raised blood levels of the muscle enzymes AST (aspartate aminotransferase) and CPK or CK (creatine kinase) are relatively common during early training in competition horses.  These enzymes are present at much higher levels in muscle cells than most other tissues and therefore their leakage into the blood is considered indicative of muscle damage.  The complication is that although muscle damage can result from an ongoing metabolic issue such as tying up, it may also occur as the result of transient over exertion.  Veterinary guidance should always be sought on how to progress with exercise and mangement if you suspect muscle problems .

Horses that have tied up recurrently may benefit from being fed a ration that is very low in starch (typically less than 15%) and equally high in digestible fibre and oil, which ensures adequate energy intake during competition training.  Current research into tying up cannot yet explain why this dietary change helps, but widespread experience suggests that in many instances it does and that it may sometimes be related to a reduction in anxiety or stress.  Once again a high intake of good quality forage is important, small frequent meals of a suitable low starch high fibre feed, in combination with other feeds such as alfalfa chaff and unmolassed sugar beet can be helpful.

Getting the basics right for respiratory health

Respiratory disease, whether highlighted by coughing, nasal discharge, or a dirty scope, can be an incresaed risk after the winter during the early stages of competition training, when the respoiratory system comes under increased stress and their immune system is challenged Numerous nutrients that may support the immune system have been investigated by scientists in man and other species, such as glutamine, antioxidants including vitamin C and E, probiotics, prebiotics, omega 3 fatty acids, adaptogenic herbs, whey protein and others.

However, before turning to nutraceuticals for all the answers, some fundamentals can be addressed.  Good clean bedding is essential, as are well-ventilated stables and clean forage. Unfortunately, our variable climate means that producing consistently clean hay can be difficult.  Whilst haylage is a viable alternative to hay, as the process of fermentation keeps the level of mould and yeast to a minimum, it is not infallible and haylage that has been produced badly, or which has become contaminated is a serious issue.  There has also been extensive research carried out on the benefits of particular hay steamers  to improve the ‘fitness to feed’ of hay.

Retention of calcium is reduced in early training

Finally a discussion of the problems of early competition training in Spring would not be complete without reference to bone.  Many of the problems encountered at this time relate to changes in bone strength and density during training.  Cerainly when a racehorse enters training for the first time their cannon bones have been shown to go through an initial period of demineralisation, which reaches its greatest severity at about 60 days into training.   Remineralisation then occurs as training progresses.  The initial demineralisation phase results partly as part of the remodelling process but also as a result of a change in the nature of the diet (less forage and more cereal).  Current thinking follows that adequate calcium content in the diet is especially important during the initial demineralisation phase, as the horse’s ability to retain calcium in the body seems to be reduced.  Attention to the calcium to phosphorus ratio of the diet is also vital, especially if top-dressing with cereals. Vitamin K1 in a bioavaiable form is also important to ensure that calcium is deposited into bone in the correct format.  Vitamin K1 status become depreseed when horses have less access to fresh pasture and spend more time stabled.

Keyflow’s Early Spring Choice for early competition training

By: Keyflow Nutritionist, Louise Scott

Perfect Balance – a perfect feed for those that need to restrict energy intake, but still require quality protein and concentrated vitamin and minerals.  Can be combined with KeyPlus for added energy as work progreses.

Keyflow Pink Mash – Low in starch and high in fibre, with added beetroot for that ‘Je ne sais quoi’ – really palatabile topdress feed for fussy feeders and those that need a low starch ration – Perfect with Perfect Balance

BoneKare – a unique patent source of vitamin K1 vital to maintain bone density and strength.

KeyPlus – A fully steam extruded rice based feed offering starch in moderation, high oil, a great source of energy for condition without excitability

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