Working your horse in the heat

[Arrow]

Should have posted this earlier, but it's been cool in Ohio--two ninety-degree days in a row now, though--the index according to this scale where I live right now is about 160!

Copied it on horse.com to COTH--it's gone from the one, but I found it on the other.:)

I usually don't bother with the wind--I just add heat and humidity.

A SIMPLE GUIDE
When Is It Too Hot For Your Horse?

From an article about the death of a horse in a show in Tennessee:

Add air temperature and relative humidity, and subtract wind speed. If your total adds up to 180 or above don't ride; if it is 130-170 use caution; 130 or below, ride!

Determine: Temperature (F) + relative humidity (%) – wind speed. For example: Temperature (F) 79, Relative Humidity (%) 58, Wind Speed 4.6 (MPH): Answer = 132.4

Less than 130: All go—horses can function to cool themselves assuming adequate hydration.

130 – 170: Caution—a horse's cooling mechanisms can only partially function as intended. Some cooling management procedures will need to be performed.

180 or above: Stop—a horse's cooling systems cannot and will not function adequately. All cooling procedures will need to be utilized to keep the horse out of serious trouble.

Why is it an issue for the horse when heat and humidity combine to equal 180+? What doesn't work and why? What are some of the physiological ramifications? What are some of the symptoms?

Heat is produced by muscles in the metabolic conversion of chemical energy, to the mechanical energy required for muscle contraction and limb movement. Seventy-five to eighty percent of the chemical energy is converted to heat, which moves from the contracting skeletal muscles, to the surrounding tissues by the flow of lymph and blood.

Assuming a comparable rate of exercise intensity, the rate of cooling or heat loss is affected by air temperature, wind velocity, and humidity. Heat can also be lost in a fourth way, conduction, which is a direct transfer of heat from the skin or feet to surfaces in direct contact (such as an ice bag on the skin).

So, thinking about the chart and the equation:
Temperature (F) + Relative Humidity (%) – Wind Speed (MPH), we see how the ability of the horse to cool itself in these four different ways will be affected:

• In cool temps with low humidity, heat loss through convection and conduction can be as much as 50%. Heat can also be lost through radiation, with as much as 60% of a body's heat lost in this way when air temperatures are cool. The numbers in our equation would add up to much less than 180, and the horse would have no difficulty cooling itself.

• As temperatures rise, the thermal gradient for heat dissipation is reduced, resulting is less convective, conductive, and radiative heat loss, and more evaporative cooling. The evaporation of water from the skin surface is the most important means of heat dissipation in high-heat/low-humidity conditions. So, when we get a high temperature reading with low humidity, a horse may still not have difficulty cooling, but if temperatures are extremely high with no wind, we might get a result above 140, which would means our horse needs our help cooling off.

• With high humidity, sweat cannot evaporate as easily, so the ability of the horse to cool itself in this important way is reduced. When high humidity is combined with high temperatures, (which we just saw reduce the effectiveness of radiant, conductive, and convective cooling) the horse has now lost all four means to cool itself, and is in a dangerous situation, subject to a greater rate of heat accumulation within his body.

[Horseaholic]

wow cool stuff. Thanks for sharing!

[Petra]

That was interesting. Thanks for sharing.

I don't really do the math to figure out whether to ride or not though. If its close to 100F outside it's not just my horse who is uncomfortable. I don't have much fun riding if I'm sweating my butt off. :D

[gabhainn]

gotta simpler formula: work till your done then quit, if I planned my days around the weather I would get nothing done................Kevin

[WashingtonBay]

That was interesting. Thanks for sharing.

I don't really do the math to figure out whether to ride or not though. If its close to 100F outside it's not just my horse who is uncomfortable. I don't have much fun riding if I'm sweating my butt off. :D

Yeah - I know for a fact my horse can take more heat than I can... I can't take the heat, so my horse's biggest safety formula is ME. :)

[Jump The Moon]

That's interesting, and probably very helpful - but like the others have mostly agreed; if it's too hot for me (which is about 25 degrees celcius) then I wont be riding until late or very early when temps drop to 18 or so :) Not that we really get heat too much anyway here where I am in the UK...:p

But thanks for sharing, hopefully is info like this is passed around there wont be so many deaths from heat, in horses and I guess humans too.

[gabhainn]

In east Texas we, unfortunately do not have the luxury of following this chart. it is over 90 degrees approximately 6-7 months a year. If we were to not ride our horses according to this scale, we would never ride. it is often over 90 degrees as late as oct and as early as april. and the relative humidity in East Texas is rarely below 90%. Cattle work here is still largely done on horseback as Livaward can attest, so the temp not only affects horseman but the cattle industry as well..........kevin

[Arrow]

Kevin--it probably doesn't really apply to horses that work for a living and are acclimated to dealing with it. But for those of us who ride 4 or 5 days a week for an hour or two, with the occasional longer ride on weekends--it's a pretty good guide to staying safe. And WB--you ride...when?:innocent:

[gabhainn]

Kevin--it probably doesn't really apply to horses that work for a living and are acclimated to dealing with it. But for those of us who ride 4 or 5 days a week for an hour or two, with the occasional longer ride on weekends--it's a pretty good guide to staying safe. And WB--you ride...when?:innocent:
oh I know I was just feeling argumentative, it struck me wrong at first thats why I went back and replied a second time........Kevin

[Arrow]

Argumentative, you? No! Luckily I always keep a cool head and never argue back...:greengrin:

[gabhainn]

http://smileys.smileycentral.com/cat/36/36_1_1.gif (http://www.smileycentral.com/?partner=ZSzeb001_ZKxdm144YYUS) http://smileys.smileycentral.com/cat/36/36_1_21.gif (http://www.smileycentral.com/?partner=ZSzeb001_ZKxdm144YYUS) http://smileys.smileycentral.com/cat/36/36_1_13.gif (http://www.smileycentral.com/?partner=ZSzeb001_ZKxdm144YYUS) ......Kevin





http://www.smileycentral.com/sig.jsp?pc=ZSzeb097&pp=ZKxdm144YYUS (http://www.smileycentral.com/dl/index.jhtml?partner=ZSzeb097_ZKxdm144YYUS&utm_id=7925)

[OwnedByOurHorses]

Here it is 95 with a heat index of 105 humidity is 48.6% add the lovely 26 mph winds that feel like some one is blowing a hair dryer on high at your skin..what I get is well below the 130-170 thing .Yet neither 2 legged or 4 legged is doing anything until dark thirty..To prevent any more cattle deaths here, local ranchers are rounding up cattle in the late evening and early hours of the morning, To take to auction ..I don't think there is a rancher here not selling off everything except their best producers due to the extreme drought we are in..

[mare]

To prevent any more cattle deaths here, local ranchers are rounding up cattle in the late evening and early hours of the morning, To take to auction ..I don't think there is a rancher here not selling off everything except their best producers due to the extreme drought we are in..

I was in the same situation 3 years ago. Not fun. They have my sympathy.

That's a pretty handy formula. I will pass it on to all the hobbyists who ask my opinion on "when is it too hot."

Sure they are times when you have to get out and do something regardless, but most are never in that situation. I used to alter my schedule or plans to avoid overheating livestock or help.

[Spyder]

32 degree C with 42 degree humidex today and we still showed over fences.

[Arrow]

Hip hip hooray, Spyder! Way to go! You are amazing, and so is the horse you rode in on!!!

[Tiz]

"the relative humidity in East Texas is rarely below 90%."

I've never been to Texas, Kevin, so I'm curious. Are you exaggerating about that, or not?

[WashingtonBay]

And WB--you ride...when?:innocent:

In my memories, mostly... we haven't done it nearly enough lately. Thanks for noticing.

[Arrow]

Well, Bay's more than earned his retirement!

[Arrow]

"the relative humidity in East Texas is rarely below 90%."

I've never been to Texas, Kevin, so I'm curious. Are you exaggerating about that, or not?

Don't think he is--I had a colleague from that part of the world once, and whenever I mentioned the horrible heat and humidity of NE Ohio, she's say "what humidity?"

[OwnedByOurHorses]

"the relative humidity in East Texas is rarely below 90%."

I've never been to Texas, Kevin, so I'm curious. Are you exaggerating about that, or not?

"Texas" period has the worst humidity. Here is south Texas it's normal 90% today is low at 48.6% only because we have high winds today. We Average 86-92% humidity here

[vicklynn]

I still try to figure out how people in MO ride this time of yr.

Heat index has been over 100 the past couple days...ugh

[gabhainn]

"the relative humidity in East Texas is rarely below 90%."

I've never been to Texas, Kevin, so I'm curious. Are you exaggerating about that, or not?
No I am not, the funny thing about Texas is se Texas is considered sub tropical, sw Texas is desert and we have any and all types in between......Kevin

[Tiz]

You are a tough bunch, aren't you? Amazing how everyone adapts to it.

[Arrow]

Good for cotton--just like much of the rest of the South East.

[WashingtonBay]

Well, Bay's more than earned his retirement!

He's not retired... just hasn't been called to work much.

Hopefully that will be changing now.

[Arrow]

How are things with the trailer--did you get it fixed?

[gabhainn]

Good for cotton--just like much of the rest of the South East.
yup yup it sure is except for right now we are in the worst drought in ages.still have 90% humidity and NO rain, its rough right now glad only have 2 cows and 1 horse at the moment. We are looking at 100 dollar round bales by Christmas and they are usu 40...........Kevin

[OwnedByOurHorses]

Good for cotton--just like much of the rest of the South East.

So long as we aren't in a drought..between the cotton,sorghum, and corn everyone averaged about 20% of their crops this harvest. We have only 3 mills up and running this year, normally we have 8. Everyday we pray for rain.

[OwnedByOurHorses]

yup yup it sure is except for right now we are in the worst drought in ages.still have 90% humidity and NO rain, its rough right now glad only have 2 cows and 1 horse at the moment. We are looking at 100 dollar round bales by Christmas and they are usu 40...........Kevin

We have a local guy trucking them out of louisiana and selling them for 65 a round bale bad part is you have to buy 38 of them.

[Arrow]

That's too bad about the drought, I just meant that that's how I think about Texas (humid, good for cotton), what with teaching about it and having a colleague with a lot of family from there.

[Arrow]

O.K.--Arrow got the day off (stall cleaning and hand grazing only with this heat index), but I'm off to go for a run...so if I don't post again in 45 minutes of so...well, it's been fun...

[Equine_Woman]

We are lucky up here in North Texas. We've had a lot of rain this year (well average amount) and the humidity is NEVER as high as down south (obvious statement of the day). When I was in College Station we rode all Summer but we had to acclimate to it slowly. . . . No time off when your training for something. Now days I don't ride as often in the Summer but our fall-spring is lovely!!! Very rarely gets below the 50s in the winter around here. . .

I had heard this info before but I seem to recall it was 150 (that is if the temp and the humidity add up to 150 don't ride. . ..) I heard that when I was down in College Station and we all laughed because we wouldn't have been able to ride even in the middle of the night in Summer. . .

And I feel for you guys down there dealing with the drought!! 3 years ago hay prices spiked to 110 a bale for us and you couldn't even find the hay. . .We had to ship squares down from Colorado to make it through winter and they were $9 a bale. . .I hope you get some good rain soon. . . they were saying on the news that you almost needed a hurricane to recover from this drought. . . I'm thinking that wouldn't help much since it'd be all at once. . just need a nice wet end of Summer. . .

[Clarzoo]

Today:

Heat index: 102 F
Humidity: 100%
Wind: 0mph

Total: 202

But that's how it is most days! I ride in the mornings or early evenings. For my area of Florida, we would rarely be in the 'ideal' zone. I see how it could be useful for areas that don't get the extreme temps.

I will say, though, that we are very careful with the heat when exercising the farms Friesians in the summer, and the drafts. They just can't handle the high temps. Our stock horses, Paso's and Andalusians do pretty well.

[OwnedByOurHorses]

they were saying on the news that you almost needed a hurricane to recover from this drought. . . I'm thinking that wouldn't help much since it'd be all at once. . just need a nice wet end of Summer. . .

Talk is that it would take 3 tropical storms back to back or a cat 3 hurricane.to get us over this...I'll take the 3 storms....Lost my home with Katrina ...

[Arrow]

Today:

Heat index: 102 F
Humidity: 100%
Wind: 0mph

Total: 202

But that's how it is most days! I ride in the mornings or early evenings. For my area of Florida, we would rarely be in the 'ideal' zone. I see how it could be useful for areas that don't get the extreme temps.

I will say, though, that we are very careful with the heat when exercising the farms Friesians in the summer, and the drafts. They just can't handle the high temps. Our stock horses, Paso's and Andalusians do pretty well.

Yeah--I think the "take care" part is the most important part. Ride in shade if you can, if you trail ride, tie a sponge to the saddle and cool the horse off when you cross a creek, that kind of thing. Don't ride too fast, etc. Just be aware of how tough it is for the horse more than it being a hard and fast rule not to ride at all.

[WashingtonBay]

How are things with the trailer--did you get it fixed?

Yeah - trailer's fixed... then we had sick ponies, and visiting company, and other chores that need done that keep getting put off, then a heat wave (speaking of this thread). And occassionally, a forum that needs attention, with all the internet weirdness the past week.

It's just not been our summer. We do hope to change it soon and have a good, productive fall. :)

[Arrow]

Fall's the best riding anyway.:)

[Country Girl 43]

Well they say it is a DRY HEAT here. But it is still hot!! The older I get the more I hate the heat.

I find that if I am moving around it's much more tolerable than just standing around. I work with the horses early in the morning while the temps are in the low 100's. We have been lucky this week. Have had a cool spell, only got up to 103 yesterday! woohoo!! It's better than 115!! :)

[WashingtonBay]

CG - I think there will be some age you pass when you'll start liking the heat again...

All the old folks from here start wintering in Yuma around 65 ;)

[Gypsy Rose]

Great article, Arrow! I was familiar with the heat plus humidity thing, but didn't realize I could subtract wind speed.

It's finally going to get warm enough here for me to actually think about doing that math for the first time this summer, lol!

[Country Girl 43]

CG - I think there will be some age you pass when you'll start liking the heat again...

All the old folks from here start wintering in Yuma around 65 ;)

Yeah, I love the heat when I am in my air conditioned house. LOL

The old folks come here for the WINTER, not the summer.... big difference. I love our winters, it's like your spring only without the rain. :) They start showing up here around the end of September and don't leave till the first of April.

[KCandAllegro'sMom]

Me? Ride in the heat? ...that's a joke right??? I hardly even ride when it's nice out...I'm not doing jack in the heat and sure don't expect my boys too - they like their fans just fine :)


But thanks for the info....in case I ever go mental and decide to ride in the heat

[offgridgirl]

Fall's the best riding anyway.:)
YAH!!! A BIG DITTO THERE!!!:cowboy::cowboy:

[offgridgirl]

yup yup it sure is except for right now we are in the worst drought in ages.still have 90% humidity and NO rain, its rough right now glad only have 2 cows and 1 horse at the moment. We are looking at 100 dollar round bales by Christmas and they are usu 40...........Kevin

It is interesting that we are in the same boat:huh:....so to speak....NO rain....very hot days and lots of humidity.:eek:

Our well is almost dry and I'm haulin' water in @ 55gal at a time for the horses and some garden plants. We go to the lake for a swim to rinse off..... The hay production was down about 30% over last year..... so we bought more.... We are expecting a very cold winter as well.....sheesh.....:doh:

[valleyrider]

Drought? I wish we could give you some of our rain cause this has been the wettest summer in years! Interesting article Arrow. But I suck at math :doh:And lots of interesting replies. We have people from all over the USA and other parts of the world. We and our animals I think adapt to our climate somewhat.. What we feel is hot in the east coast is not that hot in the west..But a good rule I think if you only ride a few times a week would be not to ride real hard when it is real hot for where you live. It is suppose to be the hottest and muggiest day so for this summer for us here in NY. I think I will be giving the boys a bath. Hosing them off will keep us all cool.