Rain Rot - How Much Is It Related to General Health vs. Environment?

[EAY]

I was interested in opinions about the causes of rain rot, particularly how much the susceptibility of the individual horse is due to his or her general health and how much is due to environmental factors (e.g. weather, paddock conditions, grooming, etc.). The reason for my question is that at the barn where I board nearly all of sixty horses now
have various degrees of rain rot. Thankfully my horses do not, but I also buy my own grain (Purina Ultium) and give them hoof and coat supplements, and they probably get more thorough grooming than many of the others, who are mostly school horses. Or perhaps I've just been lucky so far.

The BO's opinion is that this epidemic of rain rot is primarily due to our recent cool, rainy weather and then perhaps to a lesser degree because of insufficient grooming but that mostly it is out of his control (though he does treat it when it occurs). He would probably not be open to the idea that there could be nutritional factors involved or that the fact that so many of the horses are infected indicates that they might be in sub-optimal condition.

Finally, does a susceptibility to rain rot indicate any particular nutritional deficiency, or can a particular type of dietary supplementation help to prevent and/or treat it?

[JB]

Immune system.

The organisms that cause it are in the soil. Everywhere.

Poor nutrition, or nutrition that just isn't adequate for that horse, causes an immune system to not be able to handle the issue.

60 horses with rr is a problem. A huge one. One that ought to have the BO/BM taking a serious look at the management of these horses. It's NOT normal.

Thousands of horses live in the PNW for their entire lives and don't get rr.

I know of one horse who hasn't been groomed but a few times a year for several years - he's never had rr.

If the BO isn't open to it being a nutritional issue, then he'll just continue to treat the symptoms regularly, year after year.

There's a recent thread on rr and/or scratches where I've posted my experiences and opinions on the nutritional component :)

[cloudyandcallie]

Here's my practical experience with it:
one barn, horses in paddocks, mud & rain, BO's 2 - 29 yoa horses got no rain rot. (My 2 did not go out in the rain.) Other horses ranging in age from 3 to 13 did not get rain rot. When my 2 went out, my elderly TB mare would roll in the puddles, literally putting her head under water and would emerge covered in mud. No rain rot. BO fed beet pulp and no supps while I fed Buckeye and supps.

3 yrs later moved to sandy soiled location. Lots of horses there had rain rot. My mare started to get it (see threads on Listerine) and I stopped it with the Listerine. My younger WB did not have any problems. I fed Seminole and supps. Moved from there. Lots of the old and young horses at that barn had rain rot, and they fed Nutrena.

I think it is the bacteria in the soil. If horses can live in the mud and not get rain rot, then move to a sandy soiled area and start to get rain rot, I'm voting this way.

I

[tabula rashah]

I'm very partial to the general health/ diet playing the majority role in rainrot. My guys are outside 24/7 (with run-in that they don't really use) on dry-lot (or mud lot really with all the rain we've had the past year). Out of 6 horses- 1 had rainrot this summer and the one that had it was the newest addition to the herd. He has since recovered and is one the diet I have the others on- no more rainrot. I know several horses that are groomed daily, live in manacured fields, etc. and they have it something fierce-

[Posting Trot]

What JB said.

The organisms that cause rain rot are everywhere. The difference is the horse's susceptibility to them, and that susceptibility is (usually) attributable either to malnutrition, poor nutrition, or some other disease (or parasitic infestation) depressing the immune system and allowing the rain rot to set in.

If the horses are in good weight, look for some mineral deficiency in the diet.

[Fairview Horse Center]

I see rainrot more with the first few rains after a drought period, and when we have regular light rains, then no one gets it. Trying to find who/why for about 35 years, nothing is THE reason.

Healthy horses get it.
Horses with excellent nutrition get it.
Horses that are well groomed get it.

Some horses NEVER get it, even if not groomed, poor nutrition, and very muddy living conditions.

In a barn of 30 to 35 horses, most of the time 5 to 10 will get varying degrees of rainrot (maybe once a year - usually as the winter coat begins to come in). They are on the same feeding program, and all look good.

There is DEFINITELY a genetic component. I have one mare that gets some rainrot every few years. Of mine, her foals are the ones most likely to get rainrot. A couple seem to get it each year.

I also worked for a Hunter trainer who had the theory that it was most likely to happen to horses born in a different area of the country. That may be valid for my mare, as the others were all born on the farm, but her foals were too.

I worked at a farm over 30 years ago that has a dermatologist as one of the boarders husbands. He was fascinated with it, and did scrapings, and testing. He just found basic dirt.

[moonriverfarm]

I think there is something to the "nutrition" effect here. When I changed feed this summer, horses who had never had rain rot got it. Changed back to Safechoice - bye bye rain rot.

[BeastieSlave]

Well, I've got one who has been on Triple Crown Complete for over a year now (along with a few supplements for various things). The rest of the herd is also on TC feeds. He gets rr at the drop of a hat! Damn if this rain from Ida didn't make him so tender he just about dropped to the ground when I went to groom him this morning. His back is hot and he's miserable. Oh, and he has a trace clip, so he's not even as hairy as his friends.

I can't tell you how over the whole thing I am... He's on antibiotics now and I'm going to clip him out this weekend :sigh:

I believe that nutrition and general health play a big part in which beasties get rain rot, but I also honestly think that some horses are just prone to it.

[Hampton Bay]

I think some horses are just prone to it as well. My mare never gets it, and her filly has never had it. My gelding only gets scratches (but he gets those a couple times a year). My boarder's mare gets rainrot every time we have any significant wet weather. We just clipped her this past week and found a bunch of rainrot under her winter coat. Boarder grooms the mare very well before riding and never noticed the rainrot under her winter coat, so it was well hidden. I almost think it's due to sweat in this case.

But 60 horses with issues? THAT sounds nutritional. Like not enough copper and zinc.

[Equibrit]

It has ben my experience that chestnuts with chrome are more susceptible, as is any horse with a compromised immune system. The cause is always present and is opportunistic especially in damp conditions.

[shawneeAcres]

i really see no connection with ANYTHING and rainrot. However one thing I have noticed is that chestnut horses seem to be more prone to it. THis is over years and years of living in hot, humid eastern NC conditions where rainrot seems to thrive. I ahve horses living outdoors 24/7 that never get it, and many of them rarely ever see a brush. Then have horses that are stalled and groomed to perfection get it. Sometimes vice versa! ANyone who knows my horses and feeding program will tell you that they are all heatlhy and on excellent diets. It appears to be an individual suseptibility to the organisms.

[Fairview Horse Center]

It has ben my experience that chestnuts with chrome are more susceptible

That is not true here at all. None of my chestnuts have ever had rainrot, and no scratches on the white socks, even though my boys with 4 each live in a very muddy paddock.

My mare that tends to get it is a dark bay, and her bay offspring are the ones that get it. She has a chestnut daughter, and it has not been a problem for her.

My other mares have all been bay or black, and their offspring - bay, chestnut, or black have not been prone to rainrot.

One youngster though had horrible rain scald. After a heavy rain, he was covered in painful, hot rainrot looking bumps. He flinched when we even reached toward him. Two days later, with no treatment of any kind, no pain, no bumps, hair coat looked great.

We all have our theories, but like I said before, none of them have proven to be valid.

[matryoshka]

I've had plenty of horses come in with it, but it rarely recurs once I get rid of it. If it does recur, it is minor and I take care of it right away. All my horse are on 24/7 turnout. Some need blankets when it gets cold and wet.

So I think it is partly environment, partly an individual's susceptibility, and partly our care.

I subscribe to the belief that it is always in the soil/environment/close to their skin and that horses get an overgrowth or infection when their immune systems are compromised due to stress. This could be dietary stress, environmental stress, illness or even the stress of moving from farm to another. JMHO.

[murphyluv]

I think you can't pin it down to just ONE factor. Not possible.
HOWEVER, the horse could be getting the same excellent nutrition, care, environment as the next horse, could even be the same color, but will get it and the other won't. So in some ways, yes we want the best nutrition, etc, but just b/c the horse is getting "triple crown like everyone else" doesn't mean that HIS needs are met and that his immune system is functioning as well as the other horses.
Ever notice people who could eat junk food all day but never get sick? or people who try to do everything right but get sick all the time?
Don't know if it's genetics, personality (more easily stressed=stress on immune system) or what, just sometimes, your immune system isn't all that great.

[Equilibrium]

I live in Ireland so gonna have to throw environmental out the window because all of my horses should be covered in it and they're not. OK most of mine have rugs so I don't deal with the body kind. But even last years foals never had it and they stayed out with no rugs all winter.

I have one mare who when pregnant is more affected than others. When I got her she was 3 years of age and had never had proper nutrtion or worming. Her legs are doing fairly well now but I put her on a liver tonic this year for the first time coming into the fall. This has helped her tremedously.

I believe it's more of an immune system thing. But that's not to say if your horse has it, you aren't doing the correct things or aren't feeding properly. I think with my mare she missed out on proper diet early on in her life when it was crucial for her to have one. No scientific fact to back me up so just guessing.

Terri

[buschkn]

I have had several get it here and there to degrees but I have one TB who gets it horribly every year no matter what. He is well fed, well cared for, just the rest, and is (knock wood) otherwise a healthy happy horse.

Also, he definitely didn't suffer from poor nutrition or a different environment as a youngster- he was born in KY and was a pretty high dollar racehorse with excellent connections.

I think some is mgt but a lot of it is just the individuals.

[whbar158]

Like all things with horses, it depends. Personally if a large group of horses get it together I think nutrition (except for maybe if the horses are all closely related) esp if the horses have different backgrounds, breeds etc. There are just some horses that are more prone to it than others for whatever reason. But if my horse was a part of 10+ horses that all have it and all eat the same thing I would be thinking their systems are missing something.

Saying the immune system is the reason I do think is correct. The next question is why is the immune system compromised? Age, health, genetics?

[LauraKY]

Our OTTBs seem to have more problems than others, one in particular. Also has trouble with mud fever. His veins are hard as rocks, so he's been injected a lot over the years. Wonder if it was steroids and if that could be affecting his system even 3 years later?

[EAY]

Like all things with horses, it depends. Personally if a large group of horses get it together I think nutrition (except for maybe if the horses are all closely related) esp if the horses have different backgrounds, breeds etc.

These horses and ponies are not related and are all different breeds and colors and come from different backgrounds. Interestingly, now that I think about it, there is one group of six Welsh ponies who are related, and they seem to have largely resisted it, so perhaps something genetic is at work in addition to the other factors. They are all also super easy keepers and are on the plump side, whereas some of the others are definitely underweight.

I tend to agree with several of the posters that some dietary deficiency is at work, so I have resolved to brave Ida and get to the barn today to make sure the horses get their supplements.

[BeastieSlave]

I haven't ever thought about a color or breed connection before. The two that I have had the most trouble with over the years were/are solid bay OTTBs. My chestnuts, greys, black, and appy have never had problems. I've had a couple other bays who have had the odd spot of rain rot though. Of course, I think I've had more bays over the years...

[Fairview Horse Center]

As for nutrition, I managed a farm about 20 years ago, that was very nutrition oriented, and they still had horses getting it.

This farm was one Don Kapper personally worked with/visited and did the feeding program for. We had all of the hay analyzed, and he worked up what each horse needed in feed for each batch of hay. We also used the complete program of Buckeye Harvest Salt, their mineral block (no salt), and had a mineral drench that he created for us. The fields were also tested and fertilized/limed REGULARLY.

This was a breeding farm, so not horses coming and going, no competition stress. They lived in closely bonded groups that had been together for a long time and got along like sisters.

I think nutrition CAN leave a horses susceptible to it, but there are definitely other causes.

Now that I think back, I don't remember ever seeing a chestnut with much rainrot. Certainly all of the bad cases I have seen have been bay/black for 30+ years, beginning with my black QH x back in 1976 when I got him. Interesting.

[ShowMeTheGlory]

I have a 10 year old OTTB that has never had it and then bam-I moved him to a new barn in Sept. and he gets it. Nothing else in his life has changed except that move-and this has happened to pretty much every horse at this barn when they first moved here. I think it's a couple of different factors and stuff in the dirt is probably one of them.

[matryoshka]

I check all of my guys following a hard rain. There was a very nasty, hard-rain kind of storm that caused an epidemic of rain rot on horses turned out all over the county a few years ago (not every horse got it, but a noticeable number did). I know this because I trim horses and heard the talk at various locations. So I'm on the alert after a particular hard rain that saturates the coat. If they look like they might have hives, I assume it is rain rot starting and treat immediately.

I haven't noticed that one color horse gets is worse than another. Breeds? Don't know. I rarely see it on ponies, and the few times the ponies got a touch of it, all it took was brushing the scabs out. No medication needed. They seem to be very hardy and less prone to stress-related problems.

If I had to bet on one major factor, it would be the horse's immune system. When it is stressed, horses are susceptible to infection upon exposure. Trying to say why one horse gets it vs. another is about trying to figure out why some members of a family get a cold and others don't succumb. All have been exposed, but not all will get it.

If it is highly prevalent on a particular farm, I'd wonder what they are doing to cure it. It can get bad enough to need antibiotics.

[BelladonnaLily]

I'm still trying to figure it out, but here are my observations based on my herd.

My QH mare, who has been with me since birth, had a horrible case of rainrot the first year we moved here (5 winters ago) as a 4yo. Nothing since. She is mostly sheeted/blanketed during inclement weather, but sometimes it is hit or miss. My old TB mare that lives with her also got it that year and hasn't gotten it since. She does, however, get chronic scratches that if left alone, never seem to get worse. If I mess with them, they blow up and turn into lymphangitis/cellulitis/big fat mess.

My others that have been here the past 5 years don't get much in the way of rainrot. My Va Tech purchase from 10/08 came with rainrot and it got horrible over that winter. First rain this year it came back with a vengeance but we seem to have it under control earlier.

A group of ponies from another farm came with it last spring and first rain, bam, rainrot. Again, controlling it at this point. One of the ponies from that farm came 2 years ago and same story...but no rainrot this year.

So, it seems everyone gets it/comes with it the first year or so, then I don't have problems after a few years. So, I'd wager a guess that maybe it is something in the soil coupled with immune system and they must build a resistance as long as they are kept healthy. That is my best guess. It isn't that I'm so religious about grooming and mine do NOT stay in during the rain.

[myvanya]

My OTQH just got it :sigh:

He is brown(really). I groom him a lot. He is on Equine Senior with supplements including MSM, Smartflex Repair, and SmartVite Easy Keeper Grass as well as tums for Ulcer management (he is in hard work and it is preventative more than anything). He is on constant turnout with free choice hay. I am in Colorado so it is hardly wet. So....The immune system explanation might make sense in his case but I don't think any of the others do. he has been at this barn for a few years even though I have only owned him for a few months. What really bugs me is the vet was out and she didn't give me anything to do for it :(

[matryoshka]

myvanya, I've had good success mixing Listerine (original) with baby oil, half and half, and spraying it on the rain rot. Give the scabs a few days to soften, remove, respray. Repeat until the rain rot is gone.

One horse came in last Christmas during a nasty rain. He'd already been struggling with rain rot but it wasn't horrible and the lady leasing him had been treating it with MTG. Within a week of his arrival, rain rot exploded all over him from his ears to his tail, even on his stomach. My guess is that the upheaval of moving combined with the horrible weather taxed his system to the point where the rain rot got the better of him.

I sprayed the Listerine/baby oil in his scabs, saturating as well as I could, rubbed it in, didn't brush much because it hurt, and reblanketed him. A day or so later I'd remove the soft/loosened scabs and respray, rub in. It took about two weeks, but it cleared up. He had to stay blanketed because he'd lost a lot of fur during the infection. One spot on his neck was particularly hard to clear up.

This summer I read Chocomare's thread about neck worms and double-dosed him with Equimax 14 days apart (something about her descriptions reminded me of that one tough, lingering line of rain rot on his neck). No recurrence of rain rot even though we've had some nasty, cold, hard rain. I check him often so I can treat before it gets as bad as last year. I'm also not even going to try to keep him unblanketed this year. I reserve it for the nasty cold of deep winter, but I have it ready.

[PNWjumper]

EAY--where do you live?

I'm up here in the PNW and we're definitely used to wet autumn weather. But the last month or so has been one hell of a weird time period with super wet (and relatively warm) weather.

4 of mine are in blankets and are perfectly fine. The 2 without blankets have rain rot along their backs. One is my super hardy pony who has never had a touch of rain rot in 6 years of living naked in the rain. The other is another hardy horse who's never shown the slightest inclination towards rainrot or scratches or anything even remotely related....though he is a chestnut with chrome (coincidence or not!).

I had my vet out for vaccinations and she commented that she's never seen rainrot like she has lately. The warm, wet weather is just an ideal place for soil-dependent organisms. And boy do we have our fair share of mud already!

Anyhow, I do agree that you ought to look into nutrition since the whole barn has it. But I'd also look at the recent weather. In my experience there are certainly immune-compromised horses who get rain rot more than your average horse, but I would also say that the "perfect storm" of enviromental conditions could also create a situation like you described.

I have treated my guys and will be keeping them in rain sheets until the weather starts getting legitimately cold. Both were cleared up pretty quickly, and no signs of it coming back so far.

[skip916]

I think there is something to the "nutrition" effect here. When I changed feed this summer, horses who had never had rain rot got it. Changed back to Safechoice - bye bye rain rot.

Interesting that you mentioned Safechoice! My new guy was full of rainrot after our nearly constant rain since September down in GA. and he gets groomed daily and fed quite nutritiously. I tried a myriad of products on him to no avail. I just happened to switch him to Safechoice two weeks ago and this week the rainrot is nearly gone...coincidence?

[EAY]

EAY--where do you live?


I live in Maryland and we certainly have had a lot of cool, rainy weather lately, so I think that has played a part. It will be interesting to see how this last storm that we had impacts the situation.

Also the horses in dry lots seem worse affected than those in grassy fields, so perhaps some nutrient in the grass has helped. And those in dry lots who get more sun appear to be more resistant than those in shadier lots. Perhaps the sun helps to kill the organism in the soil or on the horses' backs. Maybe the extra vitamin D helps.

[TrotTrotPumpkn]

I don't think it is color/coat related...My thin-skinned TB chestnut and Selle Francais chestnut did not get it, but my friend's bay WB with the thickest most beautious coat and super fast growing freak tail and good body weight did get it...

She's also the one that stands half in and half out of the barn during a rain storm...

My two are on a different feeding program though...

But the other difference is the mare with the rain rot has more of a dip to her back than the others, so it probably "sits" there.

[Petstorejunkie]

Immune system.

The organisms that cause it are in the soil. Everywhere.

Poor nutrition, or nutrition that just isn't adequate for that horse, causes an immune system to not be able to handle the issue.

60 horses with rr is a problem. A huge one. One that ought to have the BO/BM taking a serious look at the management of these horses. It's NOT normal.

Thousands of horses live in the PNW for their entire lives and don't get rr.

I know of one horse who hasn't been groomed but a few times a year for several years - he's never had rr.

If the BO isn't open to it being a nutritional issue, then he'll just continue to treat the symptoms regularly, year after year.

There's a recent thread on rr and/or scratches where I've posted my experiences and opinions on the nutritional component :)

Agree 110%

[BeastieSlave]

Okay, say I buy into the immune system theory. It is true that my biggest 'problem' has also had ulcers in the past... What can I do to boost the immune system in a horse who seems healthy and happy, eats well, gets loads of turnout and regular vet, farrier care, worming, etc.? He looks the best he he has since we got him (9/08). Heck, he has dapples this year!

[JB]

You don't "boost" the immune system, you feed it for health :)

I say that because 'boosting the immune system" tends to make people think about something like EqStim or another synthetic boost.

It can be as simple as adding copper and zinc, both of which play important roles in the body's natural immunity (they are the "base" components of 2 types of superoxide dismutase).

so, it starts off depending on the current diet.

[BeastieSlave]

So, he might need more copper and zinc than he's getting in 10 lbs of TC Complete each day? http://www.triplecrownfeed.com/completeanalysis.php
I used to have Seminole Grass Balancer minerals available http://www.seminolefeed.com/pdf_files/grassbalancemineral_03.pdf but there's one horse who pretty much just ate it all when it was in the pasture. I can top dress feed, or make something available in the stall during feeding if mineral sups might be the answer.