Interestingly this example plus
one relating to fresh herbs like Cleavers & Cow Parsley in Part 2 reveal surprising results.
These are very relevant to our CHH message about the impact of excessive dietary potassium on the horse.
Understanding the level of potassium in your horse’s forage is, in our experience, an important asset in helping you to manage your horse’s health and well-being.
Along with Crude protein, excessive dietary potassium is one of the main causes of the issues we associate with ‘grass affected’ horses and why we suggest removing high potassium forage and feedstuffs from the diet as a first step when horses are ticking boxes on the grass affected checklist.
Getting your head around this phenomenon can be a bit of a mind bender. It certainly took me a while to recognise what is ok for my horses. Even then it’s easy to be fooled.
'Interestingly, end of last summer my hay supplier offered me some ‘nice’ hay he had left in the barn. Cut in great hay making weather, July 2018 it was three years old. Very clean, mixed, soft grasses with no obvious rye. I went over to the farm to have a look. All good I thought, so I took two large bales as part of my usual delivery and out of interest send a sample off for analysis.
Reaction from the horses:
First, I put a small net out in one of the hay boxes. Within minutes Glen had spotted it and took ownership. Then the other horses abandoned their nets and gathered around him waiting for their chance to access this hay. He didn’t let them in – he loved this hay.
Next, I mixed the new hay at 25% into all the nets. All the horses loved this, but instead of trickle feeding the new and usual supply as I intended, they rooted through the nets to pull the new first and then reluctantly picked at the rest hoping for more of the new.
At this point I started to worry. Why were they so obsessed with this hay, it looked nice and suitable, but their reaction was greedy and some unrest and bargy behaviours were becoming noticeable.
When the hay analysis arrived the results were surprising...
Potassium 2.46% Crude Protein 13% Sugars 9.1% CAB (Cation Anion Balance) 477
Potassium 1.26% Crude Protein 9.7% Sugars 11.5% CAB 295
Importantly I have learned to be mindful when the horses are overly keen on something edible and to not assume that they are seeking out something that they need.
This also raises questions about their interest in sugars – the new hay was actually lower in sugar than the original supply.
(One possible and very likely explanation – we know that horses have approximately 25,000 taste buds located on the roof of their mouth and the back of their tongue. They can distinguish between sweet, sour, salty and bitter. Whilst as individuals they can be different, in general they have an aversion to ‘acidic’ (sour) tastes and generally prefer sweet or salty. Potassium is also known to taste salty).
Before I sent the remaining bale back, I did one more little experiment. Feeding the new hay at 50/50 with my current supply I compared the horses manure the evening before when they had received no new hay for over 2 weeks and then following morning.
The photos show the difference overnight in the manure and this is just from a relatively minor change in their hay – disturbances to hind-gut flora show up in the manure when horses are grazing green grass and their hind-gut flora are victims of a sudden change caused by changes in the weather and the season.
I’m pleased to say that feeding a small amount of less than suitable forage had no long-term effects on my horses. While this is not a scientific study, it is an example of science by deduction. Having the hay analysis provided scientific evidence of the hay’s nutritional values, this enabled observations to be related to facts.
Six horses were involved, comparable to some published research. The track environment is grass free and provides a controlled environment from where observations can be reasonably made'.
Sue Dawson (Calm Healthy Horses UK)