22/10/2024
Get Grass Smart – What about ‘Sugars’?
Both Spring (and Autumn) grass are a worry for many horse owners.
So far we have covered how high nitrogen and potassium disturb not only the horse’s digestive system, but also brain, nerve and muscle function - manifesting in a wide array of ‘grass-affected’ issues.
Now spring is here you have horses that can’t think straight, are over-reactive, anxious and spooky because of mineral imbalances, who have increased energy because now the grass is also high in sugars.
When grass is in growth mode, leaf area increases and with it the capability/capacity for manufacturing sugars – soluble sugars which are used up at night when they are converted into Structural Carbohydrates (cell walls). Which is how the Fibre/Dry Matter content of the grass increases with maturity.
The trouble is it takes a few months for grass to get to the stage where it is stalky, more yellow in colour (lower in Nitrogen) and much more suitable for the equine digestive system. Even when it has reached this stage, for many horses, access will still need to be managed.
Meanwhile you have ‘lush’ grass which can easily and unpredictably exceed the less than 10% WSC** plus starch, deemed 'safe' for EMS, IR Cushing’s, PSSM and laminitis prone horses.
The soluble sugars are quickly absorbed into the bloodstream where they create both an insulin response AND immediate excess energy which, unless the horse is in a lot of work, will lead to weight gain and/or ‘behavioural’ issues.
This is why we strongly advocate NOT to expose any horses to such grass. Horses can consume a large quantity even in 30 minutes. If you own the property you can make your excess grass into hay which you can then feed throughout the year whenever the grass isn’t suitable for grazing.
It is easy to think that horses become ‘grass-affected’ because of the ‘energy imbalance’ (too much sugar, not enough work). This is where the ‘wet saddle blanket’ theory comes from. If you are not a confident rider you can allow the horse to use up the excess energy before riding, in the round-pen or on the lunge. The horse will likely zoom around, throw in a few bucks, soon running off the excess energy and be ready to ride.
As opposed to a truly ‘grass-affected’ horse where you will observe a different picture – head up with nose to the sky, eye-balls on stalks and tail up – travelling ‘hollow’, muscles are tight and they simply CANNOT round up. Their legs go in all directions and they most certainly DON’T know what they are doing! They have no self-awareness and are liable to hurt themselves or you. They get themselves into a white lather and will literally go until they drop. Not a metabolic state that more exercise and wet saddle blankets will fix!
Obviously it is critical that you can tell the difference between a horse that is simply ‘exuberant’ and feeling ‘good’ from excess energy and one that is truly ‘grass-affected’, when mineral imbalances are also contributing and they are unsafe to lunge let alone ride.
To be clear:
EVERYBODY needs to be cognizant of the sugar and starch content of their horse's diet ESPECIALLY when the horse is already overweight, EMS, IR, Cushng’s, prone to laminitis or has ‘PSSM’ type issues. Monitoring sugar levels in spring or autumn grass can present a challenge. Because they constantly fluctuate and you need to estimate the quantity your horse will consume, it is a risky strategy. The stakes are too high!
Whereas the sugar levels in hay are constant and hay can be soaked to reduce sugar levels if necessary.
The horse’s digestive system has evolved to derive energy from STRUCTURAL CARBS (fibre) via fermentation by the hind-gut flora. This is why they need a diet high in coarse fibrous material. In spring and autumn make sure they consume as much plain grass hay as possible.
Be careful with ‘extruded’ feeds – even though these reduce the likelihood of undigested starch reaching the hind-gut, they are a source of rapidly available energy – great if you can put the energy to good use but not so appropriate if you just want the quiet ride at the weekend.
**(WSC includes fructans as well as simple sugars, whereas ESC solely represents the measurement of simple sugars).
Pic: The obviously 'grass-affected' horse, hollow with legs in all directions as opposed to the merely 'exuberant' horse who tends to 'round up' and prance.
