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When Horses Become Dangerous

Fence runner
This horse wasw constantly fence running & was too dangerous to ride..Check out the short GREEN grass he was on and the fact he has worn a path into it!

People who have never personally experienced a horse in this state call it ‘bad behaviour’ and put it down to ‘lack of discipline’ or ‘lack of leadership’.

​This is erroneous thinking because...

a) the horse was perfectly OK ‘before’ and had no reason to change his personality/behaviour

b) the change in behaviour clearly correlated with the change in the grass since autumn growth or drought-breaking rains.

c) on top of that, advice was given to feed Lucerne for ulcers and such reactions are not symptoms of ulcers. For these horses Lucerne being also high in potassium and nitrogen is like pouring petrol on a fire and makes matters worse.

d) the majority of owners have already been down all the avenues – having teeth done, checking saddle-fit, having their body-worker go over the horse, treating ulcers and the horse is still the same.

It requires a different approach to feed these 'grass-affected’ horses who are extremely ‘sensitised’ and who primarily need items to be REMOVED from their diet.

Green grass needs to be replaced with high fibre (as in hay, more ‘brown and stalky’ than ‘green and leafy’) LOW <10% protein diets in order to reduce potassium and nitrogen intake down to a level the horse’s metabolism can handle.

Beware of LOW sugar or LOW GI because these feeds often contain Lucerne(alfalfa) and/or soy-meal.

Be careful to read the ingredients on the fermented forage feeds which can contain Lucerne or rye-grass and clover, unsuitable forage for these horses.

Stick to plain feeds with salt plus a high spec broad spectrum multi-mineral mix to supply daily essential nutrients - Premium or Premium MVA.

GrazeEzy, Alleviate Gold and/or SOS may also need to be added, usually temporarily to help them manage and get them back to normal.

Check out: When Not to Ride

Above pictures, Cathy on Nibbler; an extremely dangerous, Grass Affected horse at the time, he could not think straight, was prone to explosive behaviour, shied at the shadow of a blade of grass and still she kept riding him - thinking he would grow out of it or could be worked out of it! Many broken bones later (Cathy's, not Nibblers), Cathy met Jenny and everything changed for the better! See photo pf the new calm Nibbler below... Read his story here.

There are a great many people who are already very aware of the various aspects of their horse’s pasture grass that can affect his ‘temperament’.

For the vast majority of people the changes are manageable - they check things like saddle-fit, hooves and teeth, make some adjustments to the diet and carry on.

This post is for those people whose normally ‘quiet and reliable’ horse, has changed and they can’t figure out why.

Some examples -the horse started bolting through narrow spaces like gateways, or went berserk in the horse-float/trailer or gave their owner a really bad fright/fall when out riding. “It coincides with the drought-breaking rains” or “with the autumn grass growth” many people happen to mention.

Their previously quiet horse or their kid’s ponies have become ‘fire-breathing dragons’, completely ‘losing the plot’ - leaping, bucking, plunging - these are OTT reactions triggered by something ‘non-existent’ or something small that they were previously familiar with and perfectly OK about.

Some people describe the moment:

‘the switch flicks and then it is like there is nobody home’.

‘ he ‘turned into a statue’ and then it was like he didn’t even know I was there’

‘he spotted something in the distance and then flew backwards’

‘he took one step and then ‘into it!’

‘we got him on the float but he panicked when we did up the back bar and went berserk!’

A lot of people blame themselves but it doesn’t matter how good a handler/rider you are, when the horse loses his ability to think and just bolts or explodes, any of the above situations are very dangerous.

These are not matters that are fixed by ‘wet saddle blankets’ (more miles under the saddle) either. Sometimes it all happens within the first few steps!

These extreme reactions aren’t as common in other countries. If you move to NZ from somewhere you have never heard of it, or you are new to horse owning, then it is a ‘booby-trap’ you need to be aware of.

Please study the HealthChecklist so you recognise the signs and don’t get caught out.

So why does autumn grass or drought-breaking rains cause such big problems in some horses?

During a dry spell or a drought, the soil gets drier and drier until cracks appear in the ground. The cracks allow oxygen to penetrate down into the soil.

When rain finally arrives and water floods the soil there is an ‘explosion’ of microbial activity. The end result is brand new, rapidly growing green grass which is very high in potassium and nitrates. We know because we have done forage analyses on such grass.

When horses have been grazing the ‘brown stubble’ and/or hay over late summer/drought periods and then the grass suddenly greens up, their metabolism (same as for any other livestock) is rapidly overwhelmed – it takes a couple of days for the kidneys to really kick in to excrete excesses and meantime there is far too much Non-Protein Nitrogen** for the liver to process so some of it can end up floating around in the blood as ammonia. Ammonia is highly toxic to the brain.

The problem is compounded by the ‘urease’ bacteria component of the horse’s gut flora that thrive in these conditions and produce even more ammonia which then is absorbed into the bloodstream.

In livestock the ingestion of excess Non-Protein Nitrogen (NPN) causes ‘wildly aberrant behaviour’ which is referred to as “Bovine Bonkers Syndrome” !!

The symptoms of Non-Protein Nitrogen Poisoning are very similar to those of the “Fire-Breathing Dragon Syndrome” people experience under the same circumstances in their horses:

· Stampeding, (bolting, tail clamping)

· Leaping, plunging, bucking

· Twitching, (especially over the flanks and withers), trembling

· Constant circling, (just like little Dora was doing after she spent the night out on high octane red clover pasture in the last post)

· Tooth grinding, salivating

· Convulsions

Many horses may only exhibit more subtle signs so a lot of people ‘get by’ because they are confident riders and their horse doesn’t do anything serious enough to scare them.

Not so for less confident or experienced riders.

Many people are still attempting to keep their horses happy, healthy and of course ridable on pasture that is designed for ruminants like sheep and cattle. Dairy pasture is particularly unsuitable for any horse.

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