Dr Nerida Richards PhD
Equilize Horse Nutrition Pty Ltd
SPRING! For those of us with laminitis prone horses and ponies, this season can strike fear in our hearts.
With the cold nights and longer sunny days, pastures can spike as much as 30% (or more!) non-structural carbohydrate and THAT can spell disaster for our metabolic, insulin dysregulated and PPID (Cushings) equines.
You see… that non-structural carbohydrate can increase post-feeding blood glucose levels. And that rise in blood glucose can then trigger a much higher than normal rise in blood insulin.
And it is this high blood insulin that causes laminitis!
Too long on spring pastures (which can be almost no time at all for some) and before you know it your horse or pony is hobbling around or standing in that ‘rocked back on their haunches’ laminitic stance we wish we didn’t know!
Grazing in the very early morning may be OK
For some equines, any access to spring pasture is too much and they need to be ‘locked up’.
For others, very early morning grazing is OK. Non-structural carbohydrate levels are lowest in the very early morning (from just before sunrise to no more than 2 hours after sunrise), making this the safest time for laminitis prone equines to graze.
But this also isn’t a hard and fast rule.
For example, if you have a run of frosty nights and sunny days, non-structural carbohydrate levels can still be too high to be safe, even in the wee hours of the morning!!
AND THIS… leaves us with a proper problem.
Diets must be forage based!
ALL horse and pony diets should be forage based. ALL diets should contain an absolute minimum of 1.5% of bodyweight of forage. And ideally they should be fed 2% of their bodyweight in forage per day.
- For a 300 kg pony this is 6 kg per day.
- And for a 500 kg horse, it is 10 kg/day.
BUT, in spring, for those prone to laminitis, their main source of forage, their pasture, can become unsafe for them to graze.
Which means we need to find alternative, SAFE sources of forage!
If we don’t feed enough forage, serious problems like gastric ulcers, colic, dehydration, boredom, stereotypical behaviours, changes in gut bacterial balance, reduced immune function and the destruction of your trees and fences with wood chewing behaviour may occur.
So it’s critical that we feed enough forage!
What is a ‘safe’ forage?
Not all forages are safe! Which means some types of conserved forages, like ryegrass hay or oaten chaff may be equally as capable of causing laminitis as your spring pasture.
Which forages ARE safe? Before we answer that, let’s look at what we mean by ‘safe’?
To avoid a post feeding rise in blood glucose, forages should be less than 12% non-structural carbohydrate (defined as starch + water soluble carbohydrate). And to be really safe, or for particularly sensitive equines, we should aim for a non-structural carbohydrate level of less than 10% on an as fed basis.
The challenging thing is, conserved forages aren’t predictably always the same non-structural carbohydrate level.
Which forages are safe?
There are MANY factors that will affect a forages non-structural carbohydrate level.
Are they a grass or a legume?
Legumes like lucerne are limited in the amount of non-structural carbohydrate they can store so they are normally safe forages to feed and will usually contain less than 12% non-structural carbohydrate. In fact lucerne is one of my ‘go to’ safe forages for laminitis prone equines.
Grasses on the other hand are highly variable.
Their basic physiology and whether they are a cool season (C3 Type) grass or warm season (C4 Type) grass has a huge impact on their likely non-structural carbohydrate levels.
Cool season grasses (like ryegrass, oaten forages or prairie grass) are capable of storing huge amounts of non-structural carbohydrate and are usually the worst offenders when it comes to unsafe forages for laminitis prone horses.
On the other hand warm season grasses (like Teff, rhodes grass or digit grass) are limited in the amount of non-structural carbohydrate they can store and are usually our safest options when it comes to selecting grass forages for our laminitis prone horses and ponies.
And then straw comes in in a category of its own. Typically very low in non-structural carbohydrate and low in calories, straw can make a valuable diet base as it allows us to feed the bulk our laminitis prone horses and ponies need… without overfeeding calories!
A variety of forages is best!
When putting together your laminitis prone horse or pony’s diet always try to get as much fibre variety into the diet as possible!
And this means variety in forage type and also forage form.
We always need to remember horses are foragers… if left to roam free, equines will naturally select a huge variety of forage types and forms. So we need to try and recreate this as much as possible.
The fibre diversity this creates leads to bacterial diversity in the gut. And THIS creates gut ‘resilience’. The more resilient the horse or pony’s gut bacteria, the less likely they are to get ‘disrupted’. Resilient gut = healthier horse!
The diversity also supports mental stimulation and this helps to keep horses content. Something exceptionally important for their welfare!
What does a good diet look like?
I like to see laminitis prone horse diets based on low calorie (energy) grass hay or straw. Something so low in energy you can give them lots of bulk without causing weight gain. This forage I would use to make up at least 50% of the diet. And I would feed it from slow feeder hay nets or bags to extend the amount of time they take to eat it.
So for a 300 kg pony, I would feed at least 3 kg of their total 6 kg/day of this low energy forage.
For a 500 kg horse, this would be at least 5 kg of their total 10 kg/day of this low energy forage.
Then I like to add fibre variety using both species variety and form variety.
This is where you can start bringing in different types of forage species as well as different forage forms. Use additional hays, hay cubes and chaffs to make up the remainder of your horse or ponies daily forage requirement.
For example if you are feeding straw as the diet base you can start to bring in other grass types like Teff, Rhodes grass or digit grass, or all 3! And you can feed them as hay, hay cubes or chaff.
And I always (unless there is a reason not to) also feed some lucerne. Lucerne introduced legume fibre and adds a bunch of really useful nutrient including high quality protein and calcium, which can both be lacking from grass based diets.
Get creative with how you feed your forages to maintain mental stimulation. Put hay in slow feeder nets in various places around a yard or stable. Scatter hay cubes on the ground to be found or use a ‘hay cube ball’ that your horse has to work at to get the cubes to fall out!
And of course, remember to balance the diet using a low non-structural carbohydrate balancer pellet so that you are meeting all vitamin and mineral requirements. This is particularly important when feeding laminitis prone horses on straw or low-quality grass hay based diets!
Multicube Teff & Lucerne Hay Cubes
The Multicube Teff & Lucerne Hay Cubes provide the perfect forage species and forage form variety for your laminitis prone horses and ponies.
Low in non-structural carbohydrates (something that is regularly tested), the cubes are a laminitis safe forage. And are excellent for creating environmental enrichment and encouraging natural foraging behaviours. Plus with their longer stem fibres they will create more chewing and beneficial saliva production than shorter chopped chaffs.
They can easily be soaked for older horses or horses with poor teeth.