Sunbleaching or Sweat?

I think it must be a combination of both! Poet and I did an unintentional experiment over our Christmas break that seems to show that the sunbleaching that occurs in some horses over summer is a combination of sun and sweat.

Where we live flies can get bad, so my horses have flymasks on during daylight hours. It has been hot (like seriously hot… 40 degrees celcius/100 F plus) so they sweat a fair bit behind their ears where the strap for the masks sit.

Check out the bleaching pattern though on Poet who is liver chestnut and bleaches out in patches every summer… he has bleached severely where he has sweated around the mask strap, BUT under the strap, where it wasn’t exposed to any sunlight, he has maintained his coat color. Funky huh!!


Looking at him this morning he is bleached badly around his flanks and on his shoulder where he sweats the most too. So sweat + sun + a certain color and coated horse = bleaching, even when the diet is well and truly adequate for copper and zinc (thanks to FeedXL and pasture analysis I know this).

It’s interesting to note that Popcorn, who has an entirely different coat both in colour, length, thickness and even feel doesn’t bleach anywhere, ever. So specific coats seem to bleach a lot more than others. And our climate obviously contributes significantly too!


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Drought Feeding: Keeping Your Horse Healthy

While many of us in Australia have been dealing with drought conditions, increasingly we are having to turn to sources of hay outside of the commonly used lucerne, grassy/meadow, rhodes, clover, oaten and wheaten hays. Not all alternative hay types are suitable for horses however so be careful when choosing an alternative hay or chaff for your horse.

Alternative Sources of Hay and Chaff

Some suitable and unsuitable alternative hays and chaffs include:

Suitable Hay/Chaff Types:

• Well cured grass or legume silage
• Pea hay or straw
• Wheat or barley straw
• Canola hay
• Teff Hay (but don’t feed as the only hay and be aware it can be high in starch and sugars)
• Sugarcane hay (avoid for Cushing’s horses or laminitic horses)
• Vetch hay (don’t feed more than 0.5kg/100 kg bodyweight)
• Barley hay/chaff (feed with caution if it has intact seed heads with long awns, avoid for Cushing’s horses or laminitic horses)
• Triticale hay/chaff (avoid for Cushing’s horses or laminitic horses)

Unsuitable Hay/Chaff Types:

• Lupin hay (may cause lupinosis)
• Sorghum/forage sorghum hay (may cause prussic acid or hydrocyanic acid poisoning)
• Red clover and alsike clover hay/chaff (may cause liver damage and photosensitisation)

Regardless of the hay type you do choose, ALWAYS make sure it is clean and free of mould. If the hay is dusty, it should be dampened down prior to feeding.

And remember, all these different types of hay will affect what else you need to feed to keep diets balanced and meeting requirements. This is where FeedXL can help. Simply enter the hay you are feeding and check that your supplementary feeds and supplements are still able to meet requirements! Even with all the changes of hay, keeping the diet balanced will keep your horse glowing and in pristine health!

Sand and Dirt Accumulation

Horses naturally eat quite a bit of soil! Under normal circumstances however the large amount of fibre moving through their gut acts to move the sand and dirt through their gut and out in their manure… so normally it won’t accumulate. During drought however, the amount of soil they eat increases due to grazing very close to virtually bare ground. And often the amount of fibre they have access to is reduced. So it’s a double whammy… more sand and dirt in their gut and less fibre to clear it. This situation often results in accumulation of sand and dirt, irritation of the gastrointestinal tract and colic or diarrhea.

The best way to clear sand and dirt from a horse’s gut is to feed lots and lots of hay. But this isn’t always possible during a drought. An alternative and also very effective way of clearing it is to feed psyllium husk. Psyllium husk is a fibre that absorbs water in the gut and turns into a really stick goo (technical term!) that is able to shift sand and dirt out of the gut.

Interesting recent research paper here showing significant sand and dirt accumulation being successfully shifted in 4 days using a combination of psyllium husk and epsom salts…/arti…/pii/S1090023318302648…

For those of you who would like to use psyllium without nasogastric tubing it, we have good success feeding 50 grams per 100 kg of bodyweight per day. Feed it in a single meal, for 5 days in a row, mixed with something your horse loves the taste of. Make the feed very very slightly damp then tip the psyllium in and mix it around. Don’t wet it too much as most horses don’t like the taste and/or texture of wet psyllium. If your horse was showing signs of sand or dirt accumulation (mild colic or diarrhea), give the horse a break for 5 days and then repeat the 5 day treatment. You can continue to do this as long as you feel necessary.

Questions? Comments?

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How to Feed a Horse That Won’t Sweat

Anhydrosis, or the inability to sweat, is a serious condition that affects horses in hot and humid climates. Horses rely heavily on sweating to cool themselves down and keep their core body temperature within a normal range. Sweat wets the horse’s skin and then as it evaporates it takes heat with it, effectively creating an evaporative cooling system for the horse.

In some horses however, for reasons largely still unknown a horse’s sweat glands either partially or fully quit producing sweat. These horses find it very difficult to stay cool and need to resort to offloading heat via their lungs by breathing harder and faster than you would expect them to, which is why horses with this condition are often said to ‘have the puffs’.

In many situations though, puffing is not effective enough, so horses that can’t sweat are at serious risk of hyperthermia which wreaks all sorts of havoc in the body and if not dealt with effectively will eventually result in death.

The right feeding strategy may help

While we don’t understand what causes anhydrosis it does appear that for some horses certain nutritional strategies can help. Tips for feeding horses with anhydrosis include:

1. Always meet electrolyte requirements in the diet

It is likely some horses stop sweating simply because they run out of electrolytes. The major electrolytes found in sweat are sodium, chloride and potassium. The two most commonly deficient electrolytes in a horse’s diet are sodium and chloride and these are the components of ordinary old salt.

Use FeedXL to assess your horse’s requirement for the electrolyte minerals and use plain salt and/or an electrolyte supplement to meet requirements. Horse’s on forage based diets should be receiving lots of potassium from their forage so in most cases all you need to add is plain salt.

2. Always provide access to free choice rock salt

A horse will seek salt out when it knows it needs it, so providing free access to loose rock salt allows them to eat as much or as little as they need to meet their requirements.

In very hot and humid climates avoid the use of salt blocks as it is difficult for a horse to lick enough salt off to meet requirements when they need a lot of salt.

3. Feed controlled amounts of protein

Diets that are too high in protein have a couple of negative effects on horses that can’t sweat.

The first is that protein generates a lot of heat during the process of digestion and metabolism which adds to the heat load a horse needs to get rid of to keep its body temperature normal. For most horses this is usually not an issue as they are able to sweat and easily dissipate the excess heat. But when a horse isn’t able to sweat, it just makes their job of staying cool even more difficult.

The second is that when protein is fed in excess the horse needs to get rid of the excess nitrogen contained in the protein. In a healthy horse the kidneys perform this task without hassle. BUT a lot of water and electrolyte are excreted with the nitrogen, so potentially it can lead to dehydration and electrolyte deficiency, neither of which will help a horse that can’t sweat properly in the first place.

To keep protein in diets low, restrict the amount of forages and feeds that are high in protein like lucerne, copra meal, lupins, faba beans, sunflower/soybean/canola meals, pollard and rice bran and rely more on grassy pasture and hay, oils, low protein fibres like beet pulp and lower protein cooked cereal grains (where it is safe to do so). will help you to keep track of the amount of protein in your horse’s diet.

4. For horses in work, consider using a lower forage diet

When the fibre contained in forages is fermented in the hindgut a lot of heat is produced which then increases the amount of heat a horse needs to get rid of to keep its body temperature normal. By reducing the amount of forage and therefore the amount of fibre in a diet you will reduce the heat load placed on a horse.

To maintain the horse’s required energy intake you can add oil (the best option as it produces the least heat) and/or cooked grains to the diet. It is essential that you feed well-cooked grains, with extruded grains being the best option, as the starch contained within these grains will be digested in the small intestine. Feeding uncooked or poorly cooked grains will lead to a lot of fermentation and heat production in the hindgut and should be avoided for all horses in hot climates.

Please note: Never reduce forage intake below 1 kg/100 kg of bodyweight and be mindful of the increased risk of stomach ulcers for horses on low forage diets. Using slow feeders is highly recommended. It is also essential to have your horse’s stomach full of forage before it is worked.

5. Make sure the diet you feed is balanced

There is some anecdotal evidence to suggest that some mineral and vitamin deficiencies may contribute to a horse’s inability to sweat. The best way to counteract this is to make sure what you are feeding is meeting all of your horse’s requirements for macro and trace-minerals and vitamins. FeedXL.comwill make sure you can achieve this!

If you have a horse with anhydrosis it is strongly recommended you seek veterinary advice. Aggressive environmental management of these horses to keep them cool is the best way to manage their condition.

Useful management strategies include:

1. Always provide access to shade and cool to cold drinking water.

2. Keep them under fans and water misters where possible during the day.

3. Turn them out at night only if possible.

4. Only work them if your veterinarian advises it is safe to do so and then only work them during the very early morning when it is coolest and only to the level they can comfortably handle.

5. Cool them down quickly and effectively with hosing and fans post work until their rectal temperature has returned to normal.

6. If these strategies aren’t effective in keeping your horse’s body temperature within a safe range, the horse will need to be moved to a cooler climate.

Often, and again for reasons we don’t understand, horses will start to sweat again when they move to a cooler environment.

Questions? Comments?

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Cold Weather? Hay is Like Your Horse’s Heater

Do you ever wonder what is best to feed in really cold weather to help your horse stay warm? Well, the answer is hay or any type of high fibre forage really.

The fibre in hay and other forages is digested in your horse’s hindgut via the process of bacterial fermentation. A by-product of this fermentation process is HEAT!

So by feeding extra forage you are giving your horse’s resident population of bacteria more fibre to ferment… which in-turn means they will generate more heat and help to keep your horse warm. Neat huh!

Just keep in mind though that you can overdo it. Feeding more than about 3% of your horse’s bodyweight in feed per day (or more than 3 lb/100 lb BW; 3 kg/100 kg BW) will have the effect of increasing passage rate through the gut.

So while there would be more fibre for the bacteria to ferment the fibre would spend less time in the hindgut, with less time for fermentation and heat production. Catch-22!

For more tips on feeding in winter head on over to:

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Cold Weather and Calorie Requirements

Have you ever wondered how much of an impact the weather has on your horse’s calorie requirement?

While it is poorly documented in horses, observation suggests that the environmental conditions a horse is kept in can have a huge impact on their requirement for calories. Here are some of my (Nerida’s) personal observations:

Winter 2016 in the Hunter Valley, NSW, Australia

Winter 2016 was exceptionally wet and quite cold in the Hunter Valley. We really struggled to get weanlings to grow at ‘normal’ rates, even on maximum amounts of high quality feed with ample excellent quality pasture. The problem was worse on farms where paddocks were waterlogged and the weanlings simply couldn’t get dry and warm.

So instead of being able to partition calories toward growing, they were burning them all up just staying warm.

This year (2017) has been a very dry winter and weanlings are growing well on less feed and lower quality pasture. Same feed, same genetics, same farms, just different weather… and notably, not wet!

Autumn 2016 on the North Island of New Zealand

By contrast, the 2016 autumn season in New Zealand was unusually dry and warm. One farm, who had been using the same feed regime for several years (including the same quantity of feed for weanlings) started to experience weanlings with ‘contracted tendons’. There were a couple of new cases of weanlings ‘going over at the knee’ every few days. Needless to say the owners were concerned.

In the end, it came down to the weather. With the drier, warmer weather these little guys were burning less calories to stay warm and had more to use to grow and were just growing faster than they should have been. We reduced their feed and subsequent calorie intake and had no further cases.

Summer in Saudi Arabia

Broodmares and growing horses in Saudi Arabia who are housed outdoors with no air conditioning and are fully hand fed need less feed during the summer months (and excess body condition can be an issue). With such a high ambient temperature, they need virtually no calories to maintain body temperature. They also don’t move a lot because they are so hot. And this happens predictably every year.

I don’t rug my own horses so they are fully at the mercy of whatever the weather throws at them. Last year, during winter, it rained and rained. All of them had ribs showing (they are horribly easy keepers so this was exciting for me and a good thing!) by mid winter, despite having plenty of pasture available to them.

This year by contrast, it has been cold, but dry. And there is not a rib to be seen despite having been restricted to a very small part of their paddock with minimal (and I really mean minimal) pasture. The difference … rain!

As we saw in the Hunter Valley in the first example, horses can tolerate cold, dry weather easily. My horses demonstrated this perfectly this year. As soon as they get wet though, their insulation provided by their woolly winter coats that effectively traps heat close to their body is lost, PLUS when they are wet evaporative cooling (loss of heat from a wet surface) increases.

So it’s a double whammy; they can’t trap heat, plus they lose more heat. Which all combines to mean in cold, wet weather, their calorie requirement is significantly increased as they need to produce so much more heat (which they do by burning calories) to maintain their body temperature.

As you all know, calorie (or Digestible Energy) requirements vary horse to horse and are, as just discussed, also influenced heavily by the weather. So when using FeedXL, use the Digestible Energy requirement provided as a guide, but don’t be surprised if your horse is sitting above (i.e. needs more feed than is estimated) or below (needs less feed) the requirement you are given.

The only accurate way to know if your horse is getting enough calories is to use your eyes and your hands. Body condition score your horse regularly and adjust the amount of Digestible Energy in the diet up or down if your horse starts to lose or gain weight.

Or you might be like Sam and I and a whole lot of our FeedXL members and feel like you are constantly adjusting calorie intake down and making zero impact on how overweight your horses are! And like us you might then just wait and hope the next winter is wet and cold!!

Some more information about Body Condition Scoring is here for you:

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Feeding for the Season

As the seasons change so does the amount of pasture available to your horse. And as the amount of pasture changes, so does your horse’s need for supplementary feed. Failure to adjust your horse’s feeding regime correctly with changing seasons could result in an overweight, hyperactive horse or an underweight, tired mount. But is it as simple as just changing the amount of feed you are giving? We explore this in detail in the following article.

Controlling Energy

As the amount and quality of pasture changes in your paddocks, so does the amount of digestible energy (calories) available to your horse. During winter or periods of drought when very little pasture is available, performance horses often need to be provided with additional energy in the form of hay, haylage, chaff and/or pelleted, extruded or sweetfeed concentrates to ensure their daily energy requirements are met.

In the reverse, when large amounts of high quality pasture is available, the pasture alone can often go close to meeting a performance horse’s requirement for energy. When these high quality pastures are available, there is little to no need to feed additional hard feed. In the middle of those two extremes is a situation where either the quality or quantity of available pasture means additional hard feed or forages needs to be supplied to meet energy requirements.

The table below shows the energy deficit left in a working horse’s diet when excellent, fair or poor quality pasture is the only feed provided in the diet. Excellent quality pasture is able to meet 100% of this horse’s energy requirement, while the poor quality pasture leaves a 26 MJ/day energy deficit.

Pasture Conditions Energy requirement for a 500 kg horse in moderate work Amount of energy supplied by 24 hours access to pasture Energy Deficit that needs to be filled with supplementary feed
Excellent 104 MJ 104 MJ Nil
Fair 104 MJ 88 MJ 16 MJ
Poor 104 MJ 78 MJ 26 MJ

The key to knowing when to adjust the amount of feed you are feeding according to pasture conditions is regularly body condition scoring your horse to detect changes in body fatness and taking careful note of your horse’s behaviour (see FeedXL Newsletter #1). If your horse is starting to get too fat or is feeling full of itself this may indicate you are feeding too much. If your horse is losing condition or feeling flat during work pasture quality may have dropped and you may need to feed more supplementary feed.

What about minerals?

While adjusting the amount of extra feed you provide may seem simple and is something a majority of horse owners do instinctively very well, there is a catch … you need to adjust what you are feeding to control energy intake WITHOUT unbalancing your horse’s diet from a vitamin and mineral perspective.

Let’s look at an example; A horse is grazing poor quality pasture and being supplemented with 2 kg/day (4.4 lb) of alfalfa/lucerne hay and 3 kg per day (6.6 lb) of a complete feed. As spring approaches and pasture conditions start to improve the horse starts to put on some weight so its owner (wisely) reduces the complete feed being fed from 3 kg/day to 1.5 kg/day (3.3 lb) and the horse’s weight stabilises. Once the warm weather arrives, the pastures improve to excellent quality and again the horse starts to put on some weight and feels a bit fresh in its work, so the complete feed and lucerne hay is now completely removed from the horse’s diet.

This feed reduction strategy is perfect with respect to controlling energy intake and is absolutely what should happen to avoid an overweight, hyperactive horse. However, simply reducing the amount of a complete feed in a horse’s diet leaves that horse wide open to mineral deficiencies, because in reducing the amount of complete feed in the diet to control energy intake, you are also going to reduce the amount of supplementary minerals in the diet and create some mineral deficiencies. The table below demonstrates how these mineral deficiencies develop as the amount of complete feed in the diet is reduced.

Energy Copper Zinc Selenium Iodine
% of recommended daily intake provided by the diet*
Poor quality pasture + 2 kg Lucerne Hay + 3 kg Complete Feed+ 100% 129% 127% 110% 107%
Fair quality pasture + 2 kg Lucerne Hay + 1.5 kg Complete Feed+ 100% 89% 108% 82% 73%
Excellent quality pasture only 100% 44% 73% 36% 29%

*RDIs from +Well formulated commercial feed for performance horses

What is the solution?

Obviously continuing to feed the same amount of complete feed all year round to meet mineral requirements is not a feasible solution as while this will prevent mineral deficiency, it will oversupply energy requirements when pasture conditions are good, causing horses to get overweight and hyperactive. So what should you do?

The best solution is to always have a complete feed and a compatible low dose mineral supplement or balancer pellet on hand so that as you reduce the amount of complete feed to control energy intake you can add some supplement or balancer pellet to meet mineral requirements without adding unwanted calories to the diet.

Let’s look at the diets above, this time with a balancer pellet added to meet mineral requirements:

Energy Copper Zinc Selenium Iodine
% of recommended daily intake provided by the diet*
Poor quality pasture + 2 kg Lucerne Hay + 3 kg Complete Feed 100% 129% 127% 110% 107%
Fair quality pasture + 2 kg Lucerne Hay + 1.5 kg Complete Feed + 200 g Balancer Pellet++ 100% 116% 130% 106% 103%
Excellent quality pasture + 550 g Balancer Pellet++ 100% 124% 153% 103% 111%

+ Well formulated commercial feed for performance horses ++Well formulated balancer pellet

Adding the balancer pellet at different rates according to pasture conditions and the amount of complete feed being fed means you can control energy intake without causing a mineral deficiency.

Of course, not all complete feeds and balancer pellets are created as equal, so use FeedXL ( to work out which ones do actually meet all of your horse’s requirements. Also stick with products that fully disclose the nutrient analysis of the feed on the label so you can make informed choices on the best complete feeds and supplements to use for your horse.

Take Home Message

As seasons and pasture availability change so must your horse’s feed regime. In order to control your horse’s body condition and behaviour the amount of energy (calories) in the diet needs to be kept in check. To do this, the amount of supplementary feed you give will increase during times of poor quality pasture and in the reverse the amount you feed will need to be decreased when there is high quality pasture available.

However, in adjusting feed amounts up and down to match pasture conditions, be aware of the diet’s mineral balance because controlling energy intake by reducing the amount of complete feed you are giving may be inadvertently causing mineral deficiencies that will affect your horse’s health. Feeding a complete feed, together with specific amounts of a mineral supplement or balancer pellet will allow you to control energy intake whilst always meeting mineral requirements. can help you to work out which products are best to use for your horse and will show you when you are or are not meeting mineral requirements as you adjust amounts of feed in the diet.


Dr. Nerida Richards is FeedXL’s resident equine nutrition specialist. With a degree in Rural Science, a doctorate degree in equine nutrition and nearly 20 years of full time, on the ground experience in feeding all types of horses Nerida is able to help FeedXL members solve any problem they may come up against with feeding their horses. To learn more about Nerida and to ‘meet’ the rest of the FeedXL team, check out our About Us page here.


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Spring & Autumn Pastures

As temperatures warm up heading into spring or cool down heading into autumn you will start to notice your pastures changing as temperature and moisture conditions change. In spring you will usually see a rapid growth of lush pasture while in autumn, depending on the climate you may see a flush of growth similar to that of spring in warmer climates, or you may simply get a slower growth of lush pasture in cooler areas with possible early frosting. While this new growth is usually a welcome sight and means horses are able to return to or remain out on pasture, this new growth pasture can present some unique problems for horses.

Spring and autumn are well known as ‘danger times’ for laminitis and it is not uncommon to find more horses with diarrhoea, behavioural problems and colic during these periods. So what is it about pastures growing during these seasons that make them unique and how can they be managed?


Lush spring and autumn pastures can contain as little as 15% dry matter meaning they are up to 85% water. Because of the extremely high water content of these pastures horses need to graze for long periods and eat large amount of pasture to ingest their required amount of 90% dry matter feed. For example a 500 kg horse grazing a 15% dry matter pasture would need to eat over 60 kg of this pasture in order to consume 10 kg of 90% dry matter feed (equivalent to 2% of bodyweight). If pasture quantity is low (for example your pasture is overgrazed) this is a major challenge for any horse and can result in horses doing poorly on lush new pastures, even though on a dry matter basis they are very high in digestible energy and crude protein.

There is also very little fibre present in pastures during these early growth stages. Fibre that remains undigested to some extent as it passes the whole way through the digestive tract is important for the normal functioning of the gastrointestinal tract and the formation of manure. Horses that are not given an additional source of fibre when on lush young grass may experience diarrhoea and are at a higher risk of colic associated with a low gut fill.

Young, lush pastures can be high in nitrates. Nitrate is irritating to the gut and one of the most common symptoms of high nitrate intake is diarrhoea that may also be associated with mild to severe colic.


Grasses in the very early vegetative stages of growth can contain as much as 25 to 30% crude protein on a dry matter basis. While for most healthy horses this doesn’t present a problem, horses in very heavy work may find that the high crude protein level adds to their digestive heat load and will also increase urine production as the body works to rid itself of the excess nitrogen. In situations where water balance is important and water isn’t always readily available (for example in endurance horses during competition) the combination of more digestive heat and increased urination can lead to an increased risk of dehydration.

Horses that are stabled overnight or during the day and allowed to graze the remainder of the time may also experience problems associated with these high levels of protein. Excess protein causes the distinct ammonia smell often detectable when mucking out stables, which in poorly ventilated areas can cause respiratory problems for the horse.


Rapidly growing pastures contain high levels of potassium and low levels of magnesium. While not proven in horses, excessive potassium can reduce the absorption of magnesium (possibly through its effect on the DCAD, or cation, anion difference of this diet which can then affect tissue sensitivity to parathyroid hormone) and increase magnesium excretion from the body. This effect is observed in other animal species including humans. This reduced magnesium absorption, increased magnesium excretion and an already low level of magnesium in the pasture is thought to cause chronic magnesium deficiency in horses. Young rapidly growing pastures can also contain high levels of nitrate which also increases magnesium excretion from the body. Other factors associated with some pastures including low levels of selenium and a high phytoestrogen content in clover dominant pastures can also exacerbate magnesium deficiency.

Magnesium deficiency (and the resulting active vitamin B1 deficiency) can cause normally quiet, calm horses to become ‘spooky’, behave erratically and become excited easily, show signs of incoordination, muscle tenseness, soreness or twitching and in severe cases may become dangerously aggressive and exhibit unusual herding behaviour. For more information on pasture induced magnesium deficiency, read our post ‘Is pasture affecting your horse’s behaviour?


Perhaps the condition that has received the most attention in association with spring and autumn pastures is laminitis. Green pastures use the process of photosynthesis to create non-structural carbohydrates (NSC) from sunshine, water and carbon dioxide. Under good growing conditions the plant uses these NSCs as fuel for its own growth. However if the plant is stressed in any way or subjected to temperatures too low for growth to occur over several days, these carbohydrates will continue to be produced and will accumulate in the plants leaf and stem tissue for later use.

When horses with insulin dysregulation who are prone to laminitis graze these pastures with the high levels of accumulated NSC, laminitis can develop. Other characteristics of spring and autumn pastures may also increase the risk of laminitis for prone horses. For example, a study in cows and calves by Lentz et al (1976) found that high levels of potassium (infused as potassium chloride) caused significant elevations in plasma insulin and in the calves, this response was further exaggerated in magnesium deficient animals. So it is possible that the high potassium content of lush pastures coupled with an induced magnesium deficiency is contributing to laminitis by causing prolonged elevations of insulin, which presumably would be worse in insulin dysregulated animals.

High levels of nitrate have also been suggested as a cause of laminitis in horses and dairy cattle, though the role of nitrates in laminitis is not clear. Pastures that are subjected to frosts or those that contain capeweed are of particular risk for nitrates, especially following application of nitrogen fertiliser.


There are some simple management techniques you can use to reduce the negative impact of spring and autumn pastures on your horse’s health, including:

  • Provide your horses with a supplementary source of fibre in the form of hay, chaff or haylage. Give them access to free choice hay or provide them a meal of hay, chaff or haylage equivalent to at least 0.5% bodyweight (2.5 kg for a 500 kg horse) every 24 hours. This amount should be increased if pasture availability is limited. The extra fibre in these feeds will improve gut fill and manure consistency reducing the risk of colic and diarrhoea and also help your horse to consume the calories he needs when pasture water content is very high.
  • If high protein intake is an issue, provide your horse with a meal of lower protein grass or meadow hay or chaff before being turned out onto pasture. You may also need to restrict your horse’s pasture intake by using a grazing muzzle, strip grazing or extending the period of time your horse is kept off pasture with access to lower protein hay.
  • Have your spring or autumn pasture tested for mineral content and use this information together with FeedXL to rebalance any potassium and magnesium imbalance. Care must also be taken to provide enough salt to meet sodium requirements as a sodium deficiency reportedly increases the likelihood of a magnesium deficiency in some horses.
  • Manage grazing times to reduce the risk of laminitis. If NSCs are suspected as causing issues for your horse you should restrict grazing to only the very early hours of the morning, removing the at risk horse from pasture by 2 hours after sunrise. If nitrates are suspected (for example on post-drought pastures or capeweed infested pastures) horses should only be allowed to graze in the late afternoon and into the early evening. A grazing muzzle can be used at any time to reduce pasture intake while allowing the horse to move freely around the pasture. If a muzzle is used for limited periods of grazing, care must be taken to provide additional forage in the form of hay or haylage to ensure minimum forage requirements are met. FeedXL will help you to calculate your horse’s minimum forage requirement and how much additional forage must be fed each day in order to meet the minimum requirement.
  • Don’t overgraze your pasture. Pastures that are constantly very short and in the early stages of growth are the ones that are highest in potassium and nitrates and lowest in fibre and magnesium. Use good grazing management and rotational grazing strategies to allow pastures to stay at a healthy height and stage of growth. As a general rule of thumb don’t graze your pastures until they are at least 6 inches (15 cms) in height and then allow your horses to take half of the pasture and leave the other half there to photosynthesise and provide fuel for further pasture growth.


Spring and Autmn pastures are a valuable source of nutrients for your horse and managed correctly they can be fed without any issues. But to know exactly what you are dealing with and to allow you to correctly balance your horse’s diet to avoid problems you should have your pasture tested to assess energy, protein, nitrate, NSC and mineral levels (a sample should be taken in the late afternoon for the NSC analysis and in the early morning for the nitrate analysis).

Armed with a full analysis you can then use this information together with veterinary advice and a ration analysis from FeedXL that uses your pasture analysis data to come up with a ration and a feeding strategy that will lessen the risk of any problems occurring. As they say, information is power and knowing exactly what you are dealing with in your spring and autumn pastures is no exception.

We recommend the following pasture analysis laboratories: Equi-Analytical, USA (; Symbio Alliance, Australia ( and Hills Laboratories, New Zealand (


Dr. Nerida Richards is FeedXL’s resident equine nutrition specialist. With a degree in Rural Science, a doctorate degree in equine nutrition and nearly 20 years of full time, on the ground experience in feeding all types of horses Nerida is able to help FeedXL members solve any problem they may come up against with feeding their horses. To learn more about Nerida and to ‘meet’ the rest of the FeedXL team, check out our About Us page here.


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Feeding Horses in Winter

Winter can be a tricky time of year for feeding horses, especially if you have older horses or horses that lose weight easily. Feeding the right diet during winter will help keep your horses healthy and in good body condition. Here are some tips on how you can do it:

1. Prepare for Winter Early

Use late summer and autumn while the temperatures are still comfortable and the pasture and hay quality still high to get your horse in good shape for winter. All horses during this period need to be fed a balanced diet (more on this soon) to make sure they are generally healthy and their immune systems fully functional.

If your horse tends to lose weight over winter it can be fed a little more than normal during this time to get a bit of extra condition on them, so if they lose weight during winter they won’t end up being too skinny.

You should also be looking to buy hay in summer as availability and quality are high but demand is lower meaning you will get a good quality product for less than you will pay in winter.

2. Feed plenty of forage

Forage (hay, chaff and pasture) provides your horse with many of the calories they will need to maintain weight during winter. Aside from that, forage will keep your horse warm in winter. During the digestion of forages in the horse’s gut, bacteria ferment the fibrous portions. One of the ‘by-products’ of this fermentation is heat, and it is this heat that really helps a horse to stay warm during winter.

Because of the ‘warming’ properties of forage, your horse will benefit more from an additional feed of hay than an extra feed of grain, pellets or sweetfeed in very wet, cold weather.

3. Condition score your horse regularly

Don’t throw a rug on your horse in winter and leave it on for weeks on end without taking it off to check your horse’s body condition (and of course that it doesn’t have any injuries or sores that are covered by the rug). Condition scoring involves looking at areas on your horse’s body such as the top of the neck, the wither, over the ribs and over the loin to assess the amount of body fat (which we call body condition) your horse is carrying. For more information on Body Condition Scoring, click here to see our post ‘Why Body Condition Score’.

At the very least, take your horse’s rug off every week so you can check to see if your horse is losing, maintaining or gaining weight.

4. Adjust your horse’s diet to control body weight

Because you will be condition scoring your horse regularly you will know if your horse is maintaining, gaining or losing weight. Depending on what you want your horse to be doing, you may need to adjust the diet to keep your horse at the bodyweight and condition you want.

If your horse is gaining unwanted weight, you will need to reduce or remove high energy feeds like grains, pellets, sweetfeeds or oils in the diet. If your horse is losing weight that you don’t want him to lose, you may need to feed more calories in the diet. You can do this by:

  1. Feeding more hay and if you’re not already doing so feeding some alfalfa/lucerne hay.
  2. Adding high energy feeds to the diet like pellets, sweetfeeds, oil or high energy fibres like soybean hulls, copra meal or sugarbeet pulp. Use the best quality feeds you can afford and if using a sweetfeed look for one that contains either extruded or micronised grains as these are more digestible for horses.

5. Feed a balanced diet

An unbalanced diet doesn’t meet your horse’s requirements for each of energy, protein, vitamins and minerals so your horse won’t be as healthy as he could or should be. Nutrient deficiencies can lead to:

  • Weight loss
  • Muscle wastage
  • Increased susceptibility to diseases like greasy heal and respiratory disease
  • Dull, dry coat and skin
  • Brittle and slow growing hooves
  • Suppressed immune systems

While traditionally, knowing if what you were feeding was meeting your horse’s requirements was quite hard, the FeedXL Nutrition Software makes it very easy to see if what you are feeding is the right thing for your horse. FeedXL will also help you manage your horse’s bodyweight.

6. Beware of laminitis

For horses susceptible to laminitis (including overweight horses, horses with Cushing’s Disease or those who have previously had laminitis) winter can be a danger period.

If your horse is at risk you should:

  1. Restrict your horse’s access to pasture to only the very early hours of the morning up until 11 am.
  2. Feed low sugar hay and avoid hays made from ryegrass or cereals like oats or wheat.
  3. Avoid all feeds with grain or grain by-products in them.

Beware: Most feeds that claim to be grain free are NOT. Read the label of all feeds carefully. If they contain anything like bran, pollard, millmix or millrun do not feed them to a horse prone to laminitis. By ticking the ‘Laminitis’ box on your horse’s details page in FeedXL, all of the unsuitable feeds that contain grains or grain by-products will be coloured red and you will be warned not to use them.

To learn more about feeds labelled ‘grain free’ that are actually not, click here to read our post ‘Grain Free Horse Feed: What Does It Actually Mean?

7. Add a little oil to the diet

A horse’s coat can become dry and dull during winter. To help keep the coat and skin healthy, add 1/4 cup of oil to the diet.

And Finally…

Of course all the normal rules of good horse husbandry apply in winter. Feeding a well balanced diet in conjunction with good dental, hoof and veterinary care as well as a strict worming regime will help keep your horses in top shape over winter.


Dr. Nerida Richards is FeedXL’s resident equine nutrition specialist. With a degree in Rural Science, a doctorate degree in equine nutrition and nearly 20 years of full time, on the ground experience in feeding all types of horses Nerida is able to help FeedXL members solve any problem they may come up against with feeding their horses. To learn more about Nerida and to ‘meet’ the rest of the FeedXL team, check out our About Us page here.


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