Management Strategies for EMS/Insulin Dysregulation (ID)
Returning the (formerly) insulin dysregulated horse to grass
Dry lots/bare paddocks
Feeding systems
Hay nets, slow feeders
Muzzles - grazing
Paddock/track systems
Strip grazing
Risks
Research
Dry lots/bare paddocks
Feeding systems
Hay nets, slow feeders
Muzzles - grazing
Paddock/track systems
Strip grazing
Risks
Research
Returning a previously laminitic (insulin dysregulated) horse to grass
At some point following either a laminitis episode or the diagnosis of EMS/insulin dysregulation (ID), owners may have to make decisions about whether, when and how to return their horse to pasture.
A return to some access to grass will often be possible following laminitis or for a horse with EMS/ID, as long as something - whatever caused the laminitis - has changed. This might mean weight has been lost, a more healthy diet lower in sugar and starch is being fed, the horse is having more exercise and movement, and/or PPID is being successfully treated - most likely a combination of two or more of these factors.
Before considering a return to pasture:
* Using insulin testing to guide a return to grazing.
Before considering allowing a horse that has had laminitis, or above normal insulin levels after eating hay, access to grass, a resting insulin test after eating his usual hay should be normal. If insulin is above normal after eating hay, it's very likely to be above normal after eating grass - and above normal insulin suggests insulin dysregulation and increases the risk of laminitis.
Once hay-fed resting insulin is normal, there are two options:
1. carry out an oral sugar test giving Karo Light corn syrup. If this is normal, a gradual, closely monitored return to some grazing should be ok - but always discuss this with your vet first. This is likely to be the safer option.
2. start a gradual, closely monitored return to some grazing, and as soon as possible test resting insulin after the horse has been grazing. If this result is normal, it may be ok to continue. Whilst perhaps a more "realistic" test than the oral sugar test as it directly measures insulin response to that horse's grazing, fluctuations in the sugar content of the grass and amount of grass eaten are likely to mean that insulin test results may fluctuate significantly, and therefore testing insulin after a horse has been eating a small amount of low sugar grass on a cloudy morning may not give any idea of that horse's insulin levels after eating a bit more higher sugar grass on a sunny afternoon.
Remember that although a horse may have lost weight, it may still have a strong genetic tendency for EMS/ID, and therefore may need stricter management than other horses. These horses may always be at higher risk of laminitis/insulin dysregulation, but particularly if they put on weight, eat a diet with more than low levels of sugar and starch (which may mean grass has to be severely restricted or eliminated), don't get enough exercise, and/or have uncontrolled PPID.
Note that this article is about returning a horse to a reasonable amount of grass. Some horses with EMS/ID are managed successfully with restricted access to grass throughout the period of "recovering" from EMS/ID following their diagnosis, if they do not show signs of laminitis.
A return to some access to grass will often be possible following laminitis or for a horse with EMS/ID, as long as something - whatever caused the laminitis - has changed. This might mean weight has been lost, a more healthy diet lower in sugar and starch is being fed, the horse is having more exercise and movement, and/or PPID is being successfully treated - most likely a combination of two or more of these factors.
Before considering a return to pasture:
- the horse is no longer considered actively laminitic,
- insulin and glucose results should be normal/improved (or grass restricted appropriately)*,
- the horse should be or approaching his/her correct weight,
- the diet (particularly energy) should be appropriate for the horse and workload and limit sugar and starch (ideally combined simple sugar/ESC and starch should be below 10% of the diet on a dry matter basis),
- the feet should be fully realigned, i.e. correct palmar angle and breakover correctly placed so that new wall growth will be parallel with the dorsal aspect of P3, and supported/protected as necessary through the solar structures with boots and thick pads,
- and ideally the horse will be back in at least light perhaps in-hand work.
* Using insulin testing to guide a return to grazing.
Before considering allowing a horse that has had laminitis, or above normal insulin levels after eating hay, access to grass, a resting insulin test after eating his usual hay should be normal. If insulin is above normal after eating hay, it's very likely to be above normal after eating grass - and above normal insulin suggests insulin dysregulation and increases the risk of laminitis.
Once hay-fed resting insulin is normal, there are two options:
1. carry out an oral sugar test giving Karo Light corn syrup. If this is normal, a gradual, closely monitored return to some grazing should be ok - but always discuss this with your vet first. This is likely to be the safer option.
2. start a gradual, closely monitored return to some grazing, and as soon as possible test resting insulin after the horse has been grazing. If this result is normal, it may be ok to continue. Whilst perhaps a more "realistic" test than the oral sugar test as it directly measures insulin response to that horse's grazing, fluctuations in the sugar content of the grass and amount of grass eaten are likely to mean that insulin test results may fluctuate significantly, and therefore testing insulin after a horse has been eating a small amount of low sugar grass on a cloudy morning may not give any idea of that horse's insulin levels after eating a bit more higher sugar grass on a sunny afternoon.
Remember that although a horse may have lost weight, it may still have a strong genetic tendency for EMS/ID, and therefore may need stricter management than other horses. These horses may always be at higher risk of laminitis/insulin dysregulation, but particularly if they put on weight, eat a diet with more than low levels of sugar and starch (which may mean grass has to be severely restricted or eliminated), don't get enough exercise, and/or have uncontrolled PPID.
Note that this article is about returning a horse to a reasonable amount of grass. Some horses with EMS/ID are managed successfully with restricted access to grass throughout the period of "recovering" from EMS/ID following their diagnosis, if they do not show signs of laminitis.
Strategies for limiting grass - it is important to limit quantity of grass eaten and sugar content:
Note that turning horses out to graze for a short time may not be an effective strategy for controlling sugar/starch and energy intake, as in research ponies limited to 3 hours grazing soon learned to eat a lot more grass than normal in that period! |
There are great ideas for reducing grazing, encouraging weight loss and enriching your horse's environment in the When the grass is greener guide from the University of Liverpool.
Laminitis risk from grass is likely to be related to the amount of simple sugars eaten - the result of the amount of grass eaten x the amount of sugar in the grass, so
5 kg of 7% sugar grass = 350 g sugar
2.5 kg of 14% sugar grass = 350 g sugar
Eating a small amount of short, exposed to the sun, stressed and therefore high sugar grass can have the same results as eating a lot more long, shaded, non-stressed and therefore lower sugar grass - "lush" does not necessarily mean more dangerous, and this is probably why some horses seem to get laminitis when on little more than a mud patch.
If you look at your horse's field and think there's no grass on it, ask whether you see your horse eating.
If he/she is eating, there's grass!!
It can be very useful to monitor a small patch of grass that the horse can't get to, either fenced off or just outside the field - if this is long but the grass in the field is short, you can be pretty certain there is plenty of grass, and your horse is eating in - horses appear to be amazingly good at eating grass, it's probably what they are best at!
If you decide to let your formerly ID horse return to grazing, you will have to become a bit of a grass expert - you have to take responsibility for controlling his/her sugar intake. Safergrass run by Katy Watts is a good place to learn about managing grass and understanding the factors that influence sugar content (although be aware that it is now known that is it ESC (ethanol soluble carbohydrates)/simple sugars and starch in grass that affect insulin levels, and not fructans, so therefore not the whole of WSC (water soluble carbohydrate) or NSC (non-structural carbohydrate). It is possible that grass with high WSC and NSC could be safe for ID horses, as long as the ESC and starch are below 10% (or whatever that horse's limit is - horses with a stronger genetic tendency for ID or that still have weight to lose or aren't getting as much exercise as they need may require a lower threshold - say 8% total ESC and starch to keep their insulin within the normal range).
Very briefly, reduce access to grass:
in periods of rapid growth e.g. spring, after rain - increased quantity,
in periods of frost (sunny days, nights below 5'C) and drought - increased sugar,
Do not assume "weeds" are low in sugar.
More information in the webcast EMS and Ponies – Dr Nicholas Frank – 18 October 2011
University of Minnesota – My Horse University – Cummings School of Veterinary Medicine
(Full notes here).
Laminitis risk from grass is likely to be related to the amount of simple sugars eaten - the result of the amount of grass eaten x the amount of sugar in the grass, so
5 kg of 7% sugar grass = 350 g sugar
2.5 kg of 14% sugar grass = 350 g sugar
Eating a small amount of short, exposed to the sun, stressed and therefore high sugar grass can have the same results as eating a lot more long, shaded, non-stressed and therefore lower sugar grass - "lush" does not necessarily mean more dangerous, and this is probably why some horses seem to get laminitis when on little more than a mud patch.
If you look at your horse's field and think there's no grass on it, ask whether you see your horse eating.
If he/she is eating, there's grass!!
It can be very useful to monitor a small patch of grass that the horse can't get to, either fenced off or just outside the field - if this is long but the grass in the field is short, you can be pretty certain there is plenty of grass, and your horse is eating in - horses appear to be amazingly good at eating grass, it's probably what they are best at!
If you decide to let your formerly ID horse return to grazing, you will have to become a bit of a grass expert - you have to take responsibility for controlling his/her sugar intake. Safergrass run by Katy Watts is a good place to learn about managing grass and understanding the factors that influence sugar content (although be aware that it is now known that is it ESC (ethanol soluble carbohydrates)/simple sugars and starch in grass that affect insulin levels, and not fructans, so therefore not the whole of WSC (water soluble carbohydrate) or NSC (non-structural carbohydrate). It is possible that grass with high WSC and NSC could be safe for ID horses, as long as the ESC and starch are below 10% (or whatever that horse's limit is - horses with a stronger genetic tendency for ID or that still have weight to lose or aren't getting as much exercise as they need may require a lower threshold - say 8% total ESC and starch to keep their insulin within the normal range).
Very briefly, reduce access to grass:
in periods of rapid growth e.g. spring, after rain - increased quantity,
in periods of frost (sunny days, nights below 5'C) and drought - increased sugar,
Do not assume "weeds" are low in sugar.
More information in the webcast EMS and Ponies – Dr Nicholas Frank – 18 October 2011
University of Minnesota – My Horse University – Cummings School of Veterinary Medicine
(Full notes here).
Dry lots/bare paddocks
During rehab from laminitis, horses with endocrine laminitis often benefit from turnout in a dry lot or bare paddock.
Here are some great ideas for dry lots from Daisy Haven Farm
Here are some great ideas for dry lots from Daisy Haven Farm
Feeding Systems
Hampson BA, de Laat MA, Monot J, Bailliu D, Pollitt CC
Adaption of horses to a novel dynamic feeding system: movement and behavioural responses
Equine Veterinary Journal Accepted October 2012
See also:
The effect of a novel dynamic feeding system on horse behavior and movement - Brian Hampson International Equine Science Meeting 2012
Kutzner-Mulligan J, Eisemann J, Siciliano P, Smith J, Hewitt K, Sharlette J, Pratt-Phillips S
The effect of different feed delivery methods on time to consume feed and the resulting changes in postprandial metabolite concentrations in horses
J Anim Sci. 2013 Aug;91(8):3772-9. doi: 10.2527/jas.2012-5727. Epub 2013 Jun 5
Batt-Latch gate release timer - used to open gates and deliver hay nets in the middle of the night. See Swedish Horse Feeder by Alexandra Wikner.
Adaption of horses to a novel dynamic feeding system: movement and behavioural responses
Equine Veterinary Journal Accepted October 2012
See also:
The effect of a novel dynamic feeding system on horse behavior and movement - Brian Hampson International Equine Science Meeting 2012
Kutzner-Mulligan J, Eisemann J, Siciliano P, Smith J, Hewitt K, Sharlette J, Pratt-Phillips S
The effect of different feed delivery methods on time to consume feed and the resulting changes in postprandial metabolite concentrations in horses
J Anim Sci. 2013 Aug;91(8):3772-9. doi: 10.2527/jas.2012-5727. Epub 2013 Jun 5
Batt-Latch gate release timer - used to open gates and deliver hay nets in the middle of the night. See Swedish Horse Feeder by Alexandra Wikner.
Hay nets, slow feedersTo slow hay consumption, try:
|
UK
Use haylage nets with small holes, e.g. Trickle Net NB Friends of The Laminitis Site can claim 10% off orders of Trickle Nets - the voucher code is given on joining. Join FoTLS here. Greedy Feeder haynet USA Nibble Nets Slow Down hay feeder/soaker Rest of world Slowfeed Hay Saver Net |
How to use slow feed hay nets for horses - Cynthia Cooper - Natural Horse World
Mayara Gomes Correa, Camilla Ferreira Rodrigues e Silva, Lucas Antunes Dias, Sérgio da Silva Rocha Junior, Freddy Rodrigues Thomes, Luiz Alberto do Lago, Armando de Mattos Carvalho, Rafael Resende Faleiros,
Welfare benefits after the implementation of slow-feeder hay bags for stabled horses,
Journal of Veterinary Behavior July-August 2020 Vol 38 pags 61-66, published online May 2020. https://doi.org/10.1016/j.jveb.2020.05.010.
Using a hay bag increased hay consumption time by 87%, decreased abnormal behaviours and coprophagia, and it was concluded that using a slow-feeder bag improved the welfare of stabled horses.
Research found that horses take longer to eat hay in smaller holed haynets - using a hay net with 3.2 cm holes meant horses took on average 6.5 hours to eat their ration, compared to 3.1 hours for presumably the same size ration when fed on the ground and 3.4 hours when using a large holed haynet.
Glunk EC, Hathaway MR, Weber WJ, Sheaffer CC, Martinson KL
The effect of hay net design on rate of forage consumption when feeding adult horses
Journal of Equine Veterinary Science published online 19 May 2014
Mayara Gomes Correa, Camilla Ferreira Rodrigues e Silva, Lucas Antunes Dias, Sérgio da Silva Rocha Junior, Freddy Rodrigues Thomes, Luiz Alberto do Lago, Armando de Mattos Carvalho, Rafael Resende Faleiros,
Welfare benefits after the implementation of slow-feeder hay bags for stabled horses,
Journal of Veterinary Behavior July-August 2020 Vol 38 pags 61-66, published online May 2020. https://doi.org/10.1016/j.jveb.2020.05.010.
Using a hay bag increased hay consumption time by 87%, decreased abnormal behaviours and coprophagia, and it was concluded that using a slow-feeder bag improved the welfare of stabled horses.
Research found that horses take longer to eat hay in smaller holed haynets - using a hay net with 3.2 cm holes meant horses took on average 6.5 hours to eat their ration, compared to 3.1 hours for presumably the same size ration when fed on the ground and 3.4 hours when using a large holed haynet.
Glunk EC, Hathaway MR, Weber WJ, Sheaffer CC, Martinson KL
The effect of hay net design on rate of forage consumption when feeding adult horses
Journal of Equine Veterinary Science published online 19 May 2014
Paddock/track systems
Setting up a track around a field can work really well if you have ID and non-ID horses that you want to keep together - the non-ID horses can spend time in the centre of the field where there is plenty of grass, and the ID horses can stay on the track. This way they can always see each other, and will still help exercise each other and possibly even still be able to mutually groom over the fence, but with limited grass for the ID horse.
www.paddockparadise.wikifoundry.com
Rockley Farm blog - tracks
www.paddockparadise.wikifoundry.com
Rockley Farm blog - tracks
Strip grazing
Strip grazing can help to limit grass intake. Some hints: 1. Use 2 fences - one in front of the horse, onto the new grass, and one a distance behind, so that grazed grass can rest and grow again (ready for the horses to return to it in a few weeks' time), and so that horses can't graze grass too low and damage grazing areas. This also keeps the area for collecting dung smaller. Make sure horses do have enough room to socialize, roll and move though - if possible attach the strip grazing area to a grass free area. However, note that research by Annette Longland found that ponies did not gain more weight if a back fence was not used when strip grazing*. 2. The best time to move the forward fence to give more grass is as early morning, before the sun increases sugars in the grass. On cloudy days this isn't so important, and during frosty conditions (sunny days and nights colder than 5'C) it's best not to give new grass at all, as sugar levels will remain high overnight. Remember, sun = sugar. 3. Keeping in mind point 2, it might be best to move the fence a small amount 2 or 3 times a day, rather than moving the fence by a larger amount once a day. Perhaps early in the morning and last thing at night. 4. Don't be tempted to move the fence more than you had planned. Horses are very good at gobbling down fresh grass then telling you they are starving! If you are restricting grass quite severely, provide hay so that you know they do have enough fibre to eat. 5. Use electric fencing, make sure it works and keep it on! A low strand may be needed to stop horses grazing under the fence, and a high strand for horses to stop them leaning over the fence. |
6. Can you combine strip grazing with a track system, so that horses always have access to a reasonably grass free track to encourage exercise, with small amounts of grass available around the track. Opening up small amounts of grass well spread out around the track encourages horses to move between the grassy areas, increasing exercise.
Research using strip grazing
*Longland, AC, Barfoot, C, Harris, PA
Strip-grazing: Reduces pony dry matter intakes and changes in bodyweight and morphometrics
Equine Vet J. 2021; 00: 1– 8. https://doi.org/10.1111/evj.13416
See also Can strip grazing really help to control your horse's weight - Bella Fricker, Spillers, 11 June 2021
Strip-grazing: Management Tool to Fight Obesity - KER, June 2021
*Longland, AC, Barfoot, C, Harris, PA
Strip-grazing: Reduces pony dry matter intakes and changes in bodyweight and morphometrics
Equine Vet J. 2021; 00: 1– 8. https://doi.org/10.1111/evj.13416
See also Can strip grazing really help to control your horse's weight - Bella Fricker, Spillers, 11 June 2021
Strip-grazing: Management Tool to Fight Obesity - KER, June 2021
Risks
There can be risks associated with using some slow feeder systems.
Abnormal tooth wear has been associated with use of grazing muzzles and/or starvation paddocks with very short grass. It is sometimes suggested that haynets may also adversely affect teeth, and haynets can put horses at risk of getting a foot caught, particularly if the horse is shod and if the haynet is not hung high enough. Slow feeder systems may cause frustration and anxiety and horses should be taught to use them if necessary, or start with a large holed haynet and make sure a horse understands how to use that before going to a small holed haynet, and perhaps pull a few strands of hay out to help get the horse started. It has also been suggested that some slow feeder systems may cause unnatural eating positions and lead to orthopaedic issues. Slow feeder systems like any equipment used around horses must be checked regularly for wear, breakages, sharp edges and anything that could injure the horse.
Horse Slow Feeder Safety - Christa Leste-Lasserre, thehorse.com April 2021
There can be risks associated with using some slow feeder systems.
Abnormal tooth wear has been associated with use of grazing muzzles and/or starvation paddocks with very short grass. It is sometimes suggested that haynets may also adversely affect teeth, and haynets can put horses at risk of getting a foot caught, particularly if the horse is shod and if the haynet is not hung high enough. Slow feeder systems may cause frustration and anxiety and horses should be taught to use them if necessary, or start with a large holed haynet and make sure a horse understands how to use that before going to a small holed haynet, and perhaps pull a few strands of hay out to help get the horse started. It has also been suggested that some slow feeder systems may cause unnatural eating positions and lead to orthopaedic issues. Slow feeder systems like any equipment used around horses must be checked regularly for wear, breakages, sharp edges and anything that could injure the horse.
Horse Slow Feeder Safety - Christa Leste-Lasserre, thehorse.com April 2021
Research
Cameron A, Longland A, Pfau T, Pinnegar S, Brackston I, Hockenhull J, Harris PA, Menzies-Gow NJ
The Effect of Strip Grazing on Physical Activity and Behavior in Ponies
Journal of Equine Veterinary Science Volume 110 March 2022, 103745, doi.org/10.1016/j.jevs.2021.103745.
Keywords: Strip Grazing, Activity, Pony, Behaviour
Longland AC, Barfoot C, Harris PA
Strip-grazing: Reduces pony dry matter intakes and changes in bodyweight and morphometrics
Equine Veterinary Journal January 2022 Vol 54 Issue 1. https://doi.org/10.1111/evj.13416
Cameron A, Longland A, Pfau T, Pinnegar S, Brackston I, Hockenhull J, Harris PA, Menzies-Gow NJ
The Effect of Strip Grazing on Physical Activity and Behavior in Ponies
Journal of Equine Veterinary Science Volume 110 March 2022, 103745, doi.org/10.1016/j.jevs.2021.103745.
Keywords: Strip Grazing, Activity, Pony, Behaviour
Longland AC, Barfoot C, Harris PA
Strip-grazing: Reduces pony dry matter intakes and changes in bodyweight and morphometrics
Equine Veterinary Journal January 2022 Vol 54 Issue 1. https://doi.org/10.1111/evj.13416