Anhidrosis / No Sweat & Panting

[Kino]

Anyone got any recommendations for supplements to encourage sweating in a horse who seems to be suffering from anhidrosis? Vet has been, took bloods which were normal, tested clear for Cushings.

Background: Horse coming back into work from mid-June onwards after a long period off due to various issues e.g. abscesses. Noticed he wasn't really sweating at all but put it down to the low-intensity work. Beginning of August, first fast / laboured breathing session (nostrils flaring, high resp rate, sides heaving) for approx 20-30 minutes work. No sweat and I was surprised because 1. it was hot and 2. he had worked hard.

This happened 2-3 times more before start of Sept, always on warmish days. Never as bad as the first time as I was hyper alert to it by that point and didn't want to push too hard. Then we had vet, clear bloods, heart and lungs sounded fine, she thought give it another couple of weeks of getting him fitter and then Bute trial in case it's pain (this will be happening next). She felt the no sweat wasn't important / relevant as his heart was recovering really fast after exercise and so she wouldn't expect much sweat anyway (? I feel like I misunderstood this as it doesn't make lots of sense to me!)

Since then no reoccurrence but the weather has been cooler. I was also away for a week. Which brings us to today where it is 24 degrees, he has a full winters coat, he started heavy breathing in our warm up walk which sort of makes me think it IS heat related in which case I would really like to see him sweat even a little.

He's on Applelytes and I started him on additional salt beginning of September. He's also on the Progressive Earth ProHoof Balancer. Google says give him a Guinness for breakfast which I'm actually considering trying and I know there are a couple of US companies that do specific supplements but does anyone have any other experiences & recommendations for anything similar?

Thanks in advance

 

[I'm Dun]

Ive messaged SEL whose mare had this to see if she can help

 

[Kino]

Ive messaged SEL whose mare had this to see if she can help

Thank you very much, I really appreciate it

 

[PinkvSantaboots]

If his got a full winter coat it sounds like cushings to me that's not normal, the basic blood test is not reliable I have had negative results when I knew the horse had cushings from the symptoms.

I would ask your vet for a prascend trial or go for the more advanced stim test to be sure.

My cushings horse only had one symptom and that was not shedding his coat properly so his clipped all year and on half a prascend as his results were borderline.

 

[SEL]

My mare had anhidrosis following a guttural pouch wash back in 2017. It was summer onset and an absolute nightmare. She'd start sweating again in Autumn and stop every spring. Summer of 2019 and 2020 when we had temperatures over 35 had her collapse once so I'd have to take time off work to pour water over her. It's not common in the UK at all but very common in Florida where all the research has taken place.

I'm afraid I tried all the supplements including the voodoo ones (!) & nothing helped. What did cure it is her being given thyroid meds in 2021 when she had a swollen thyroid (inconclusive blood test). All of a sudden I had sweat and she has sweated pretty normally in 2022/23. Turns out in humans the meds can cause excessive sweating as a side effect so must have reset her system.

Levothyroxin is used off licence in horses but has been widely used for EMS so is safe. Personally rather than trying all the voodoo supplements (although mine did like a Guinness mash) I'd ask your vet to trial it. It might be worth waiting until next summer though to see if you have summer onset anhydrosis or just a one-off blip.

 

[j1ffy]

I had a horse in Hong Kong with anhidrosis - after a lot of research I imported some OneAC from the USA and it worked well. He started to sweat and the following summer sweat up like a normal horse. The delivery and customs charges were multiple times the cost of the supplement so it was a relief to only need it once!!

 

[Kino]

Thanks all, that's really helpful

Pinkvboots - thanks, it's something I need to discuss again with vet. Had to push a bit for a Cushings blood test to begin with but given I felt he was late shedding in spring, definitely worth pursuing.

SEL - that's very interesting, sounds like an absolute nightmare for you though! I'm hoping the temperature is going to revert to normal October levels shortly and then hopefully he might remember how to sweat again. But will definitely be asking the vet about Levothyroxin if not.

J1ffy - I had thought of trying the OneAC when it first started but proved either tricky or expensive to get in the UK and a bit 50/50 whether it worked or not from people who had tried it. Nice to hear of success stories though!

 

[SEL]

Thanks all, that's really helpful

Pinkvboots - thanks, it's something I need to discuss again with vet. Had to push a bit for a Cushings blood test to begin with but given I felt he was late shedding in spring, definitely worth pursuing.

SEL - that's very interesting, sounds like an absolute nightmare for you though! I'm hoping the temperature is going to revert to normal October levels shortly and then hopefully he might remember how to sweat again. But will definitely be asking the vet about Levothyroxin if not.

J1ffy - I had thought of trying the OneAC when it first started but proved either tricky or expensive to get in the UK and a bit 50/50 whether it worked or not from people who had tried it. Nice to hear of success stories though!

I made up my own version of oneAC but it did nothing. Guinness mash is cheap though and I had very happy horses - especially the companion horse who ended up having Guinness specials whenever I felt he needed a treat!

I also had a few acupuncture sessions & it was one of those vets who told me it's thought to be the central nervous system misfiring so needs to be "tricked" into sweating again.

 

[PurBee]

To add to SEL’s experience - in humans not sweating is very commonly linked with hypothyroidism. As a first port of call, you’d want to know if there’s any iodine in the pony’s diet, as the thyroid wont produce thyroid hormones without iodine.
Iodine is usually added as a minimal amount in some commercial balancers, so worth checking current bagged feeds to see if there is any iodine going into the diet, and if not, consider a trial of adding ground seaweed, or getting a specialist equine thyroid supplement that likely will also contain other thyroid-dependent nutrients aswell as include iodine.

The above is what you can nutritionally add before considering Levo T3 medication.

 

[palo1]

As a bit of a curve ball, I wonder if it is worth considering further respiratory issues/diagnostics? I have a horse who had a respiratory illness which left her with allergic asthma. She didn't sweat at all during a horrendously hot period and that made things worse for her, though that was probably actually a response to the heat in itself. She is doing really well now (and sweats!) but certainly on hot days her breathing and recovery rate are not always 'normal'. A number of things, including heat, particularly where there is more humidity, can trigger her. The only way to find out if there is an allergic/asthma response would be to scope your horse but it may be totally irrelevant - I just thought your horse's symptoms resonated with me a bit!

 

[SEL]

To add to SEL’s experience - in humans not sweating is very commonly linked with hypothyroidism. As a first port of call, you’d want to know if there’s any iodine in the pony’s diet, as the thyroid wont produce thyroid hormones without iodine.
Iodine is usually added as a minimal amount in some commercial balancers, so worth checking current bagged feeds to see if there is any iodine going into the diet, and if not, consider a trial of adding ground seaweed, or getting a specialist equine thyroid supplement that likely will also contain other thyroid-dependent nutrients aswell as include iodine.

The above is what you can nutritionally add before considering Levo T3 medication.

I went down that route as well (I was the google research anhydrosis 'expert'). She actual had a normal thyroid on blood tests for years until we went to a yard where I think there was an environmental issue. The fields had flooded 2 winters in a row and it was only some time after we left we realised Thames Water let their sewage station flood in that direction. It would explain why the medication did nothing for her thyroid, which promptly came down to normal within a fortnight of moving yards.

But I will be forever grateful for spending the money given it did trigger her sweating. It is unbelievably stressful in the summers we have had for the past few years knowing she couldn't cool down naturally.

 

[PurBee]

I went down that route as well (I was the google research anhydrosis 'expert'). She actual had a normal thyroid on blood tests for years until we went to a yard where I think there was an environmental issue. The fields had flooded 2 winters in a row and it was only some time after we left we realised Thames Water let their sewage station flood in that direction. It would explain why the medication did nothing for her thyroid, which promptly came down to normal within a fortnight of moving yards.

But I will be forever grateful for spending the money given it did trigger her sweating. It is unbelievably stressful in the summers we have had for the past few years knowing she couldn't cool down naturally.

Incredible that Thames Water didnt warn down-stream owners of grazing animals!

Glad you got that all figured out and moved yards for recovery. Sometimes the environmental triggers are hard to pin-down.

 

[Goldenstar]

My much missed horse Fatty suffered from this .
He at times would show a weak sweating response but most of time non .
He was a hunter and if he had been a say an eventer it would have been career ending .
My vet did not accept what I was saying at first either .
The thing that pushed me to push it with the vet was seeing Fatty in gathering darkness hunting on a fast day when I let the field across the road the other horses where running sweat Fatty was not he was dry .
I was digesting the observation when my OH rang very upset saying Fatty had broken down I told him to get him to a road and picked them up.
My first observation was that Fatty was not broken down he was evenly weight bearing ,I thought he might have tied up but no he had not he was happy to move as walked to wards him I could feel this strange dry heat coming off him I realised it was heat exhaustion he had got so hot he stopped .
We got him cooled down and got him home then I demanded action from the vets .
He had a test where different strengths of adrenaline where injected in a line into his neck what’s supposed to happen the milder spot get a weaker sweating response and it takes longer to appear .Fatty reacted weakly and slowly to the two strongest sites .
He had almost no functional ability to sweat .
Fatty had been dangerously ill previously when a virus damaged his heart he was lucky to come back after that he had modular sarcoids also linked to this issue.

Over his life he went through periods of sweating weakly and then pretty well stopping again .

 

[SEL]

Incredible that Thames Water didnt warn down-stream owners of grazing animals!

Glad you got that all figured out and moved yards for recovery. Sometimes the environmental triggers are hard to pin-down.

We were lucky to get even a warning they'd shut the flood gates. As far as they were concerned we weren't in the area that was designated flood plain - although more than once we had to wade through water that had come up overnight to drag the poor horses out.

The sewage overspill was a nasty surprise after they'd had some bad PR and showed the stream they emptied into. The very same stream that apparently wasn't flooding the fields annually. Once I knew that was happening a lot of health issues made sense

 

[Kino]

We were lucky to get even a warning they'd shut the flood gates. As far as they were concerned we weren't in the area that was designated flood plain - although more than once we had to wade through water that had come up overnight to drag the poor horses out.

The sewage overspill was a nasty surprise after they'd had some bad PR and showed the stream they emptied into. The very same stream that apparently wasn't flooding the fields annually. Once I knew that was happening a lot of health issues made sense

That's so awful. Thames Water are a nightmare round here - there were rumours something similar had happened at a yard near me where the horses came down with a form of grass sickness. Really hope no horse from your yard suffered any long term consequences.

I'm lucky at the mo in that my stable during the day keeps fairly cool during the time he's in. His field doesn't have much shade but does have a shelter which he has taken to going into when he's first turned out in hot weather as it's cooler in there until the sun drops behind the hill. But if he was in full work / not on DIY so I see him 3 times a day and can give a quick wash down to cool off it would be a total nightmare.

 

[Kino]

To add to SEL’s experience - in humans not sweating is very commonly linked with hypothyroidism. As a first port of call, you’d want to know if there’s any iodine in the pony’s diet, as the thyroid wont produce thyroid hormones without iodine.
Iodine is usually added as a minimal amount in some commercial balancers, so worth checking current bagged feeds to see if there is any iodine going into the diet, and if not, consider a trial of adding ground seaweed, or getting a specialist equine thyroid supplement that likely will also contain other thyroid-dependent nutrients aswell as include iodine.

The above is what you can nutritionally add before considering Levo T3 medication.

Thanks PurBee - this is the kind of thing I have v little knowledge about and get bogged down in any late-night googling! Will review his iodine levels in feed / balancer at the mo.

As a bit of a curve ball, I wonder if it is worth considering further respiratory issues/diagnostics? I have a horse who had a respiratory illness which left her with allergic asthma. She didn't sweat at all during a horrendously hot period and that made things worse for her, though that was probably actually a response to the heat in itself. She is doing really well now (and sweats!) but certainly on hot days her breathing and recovery rate are not always 'normal'. A number of things, including heat, particularly where there is more humidity, can trigger her. The only way to find out if there is an allergic/asthma response would be to scope your horse but it may be totally irrelevant - I just thought your horse's symptoms resonated with me a bit!

Definitely also something to consider! If we continue having problems the vet will be back out, I think she wanted to see how things progressed - i.e. as weather changed / he got fitter / lost a bit of weight. Also she came on a not hot morning when he breathed like a totally normal horse and I looked like a mad owner

My much missed horse Fatty suffered from this .
He at times would show a weak sweating response but most of time non .
He was a hunter and if he had been a say an eventer it would have been career ending .
My vet did not accept what I was saying at first either .
The thing that pushed me to push it with the vet was seeing Fatty in gathering darkness hunting on a fast day when I let the field across the road the other horses where running sweat Fatty was not he was dry .
I was digesting the observation when my OH rang very upset saying Fatty had broken down I told him to get him to a road and picked them up.
My first observation was that Fatty was not broken down he was evenly weight bearing ,I thought he might have tied up but no he had not he was happy to move as walked to wards him I could feel this strange dry heat coming off him I realised it was heat exhaustion he had got so hot he stopped .
We got him cooled down and got him home then I demanded action from the vets .
He had a test where different strengths of adrenaline where injected in a line into his neck what’s supposed to happen the milder spot get a weaker sweating response and it takes longer to appear .Fatty reacted weakly and slowly to the two strongest sites .
He had almost no functional ability to sweat .
Fatty had been dangerously ill previously when a virus damaged his heart he was lucky to come back after that he had modular sarcoids also linked to this issue.

Over his life he went through periods of sweating weakly and then pretty well stopping again .

Thank you - I've read about Fatty before, he sounded like an awesome horse. Really sorry you've lost him. Again, when I have the vet out again I will push for more ideas / diagnostics from her. At least the weather seems to be finally changing to more autumnal days round here (never thought I would be wishing for that!!!)

 

[Goldenstar]

If you google non sweating syndrome you will find stuff from the US.
Horses can suffer sudden onset of anhidrosis when they get moved from a temperate zone to a more tropical one . It occurs if horses get moved from the Europe to say Singapore .

Since I had Fatty I realise that quite a few horses have a partial disorder with sweating because people with horses with issues knew about Fatty as he was spectacularly noticeable out Hunting and would ask me .

what I found
losing weight helps they are much much happier slim .
obviously clipping is important and managing them in hot sunny weather .
Fatty had blood tests he had muscle biopsies he had everything under the sun tested for.
It was thought he had an autoimmune issue linked to the heart issue caused by the virus .

Fatty was epic I miss him every day.

 

[PurBee]

We were lucky to get even a warning they'd shut the flood gates. As far as they were concerned we weren't in the area that was designated flood plain - although more than once we had to wade through water that had come up overnight to drag the poor horses out.

The sewage overspill was a nasty surprise after they'd had some bad PR and showed the stream they emptied into. The very same stream that apparently wasn't flooding the fields annually. Once I knew that was happening a lot of health issues made sense

It is shocking the amount of sewerage that gets deposited into fresh waterways with the authorities knowledge. I was looking at properties in the east anglia fens, one place had detailed reports/surveys posted online in their brochure - one of them showing a household wastewater map of the local houses, all being discharged into the nearby agri fields dykes/large ditches - no sewerage treatment at all!
I know those fen dykes were crystal clean water in the late 70’s as relatives would fish the dykes there regularly. There was record-breaking large pike in them too. I suppose they have all died-off from toilet duck poisoning and the like. I was completely shocked to see that map of blatant dumping of sewerage.
I hope any local farmers/horse owners dont allow grazing stock to drink from those ditches these days!

Sorry OP for slight derail - environmental toxins can account for anomalous illnesses owners of grazing animals experience, theyre just harder to pinpoint, but always worth considering.

 

[Kino]

Updating this for anyone who happens to search for a similar issue in the future. This summer (if you can call it that!) my horse is sweating normally and no breathing issues.

Could be many factors e.g. cooler summer, different pollens etc. but I have also taken him off the token (small, think 30ml, supplement scoop equalling approx 25g) of linseed meal he had in his meals. Which sounds bonkers but his coat state immediately improved within 2-3 weeks of removing it, far less dry / scurfy and we haven't had any issues with that since. There's also a growth ring on his hooves which I think coincides with removing the linseed & hoof seems to be growing in tighter above. As I say, many different factors could be playing a part but something to consider for anyone who stumbles across this in the future!

 

[Pearlsacarolsinger]

Updating this for anyone who happens to search for a similar issue in the future. This summer (if you can call it that!) my horse is sweating normally and no breathing issues.

Could be many factors e.g. cooler summer, different pollens etc. but I have also taken him off the token (small, think 30ml, supplement scoop equalling approx 25g) of linseed meal he had in his meals. Which sounds bonkers but his coat state immediately improved within 2-3 weeks of removing it, far less dry / scurfy and we haven't had any issues with that since. There's also a growth ring on his hooves which I think coincides with removing the linseed & hoof seems to be growing in tighter above. As I say, many different factors could be playing a part but something to consider for anyone who stumbles across this in the future!

That's interesting! My cob can't tolerate linseed, it causes her to have skin issues.

 

[SEL]

Updating this for anyone who happens to search for a similar issue in the future. This summer (if you can call it that!) my horse is sweating normally and no breathing issues.

Could be many factors e.g. cooler summer, different pollens etc. but I have also taken him off the token (small, think 30ml, supplement scoop equalling approx 25g) of linseed meal he had in his meals. Which sounds bonkers but his coat state immediately improved within 2-3 weeks of removing it, far less dry / scurfy and we haven't had any issues with that since. There's also a growth ring on his hooves which I think coincides with removing the linseed & hoof seems to be growing in tighter above. As I say, many different factors could be playing a part but something to consider for anyone who stumbles across this in the future!

That's odd because my one that didn't sweat couldn't tolerate linseed either!! For her it was itchy skin and seemed to be a bit of a PSSM trigger. She was only getting the amount in a balancer but that seemed to be enough to cause problems.

I try to avoid feeding it now because I think it makes the microcob itch too.

 

[palo1]

My Welshie can't tolerate linseed: it provokes a raised respiratory rate and possibly doesn't help her in the heat either. Frustratingly, it is one of those things that are regularly included in respiratory supplements.