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  Discussion on Hay question - mildew spots?
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Member:
stek

Posted on Monday, Jan 30, 2012 - 12:59 am:

Due to extremely high general humidity in our area, I've noticed tiny (pencil lead size) spots of what appears to be mildew on the outside edge of some of the bales in our stacks. Basically any edge bales that have been exposed to the air.

The hay was put up clean and dry, no problems on the inside of the bales. No mold, no weeds, nice clean 1st cutting grass hay. The 'mildew' spots don't penetrate the bales at all, they are entirely superficial. I've seen this every year in the wintertime in wet climates and have always just brushed it off and fed the hay.

We have some new boarders that think this is 'moldy hay' and say that we should throw it all out. I wanted to get some opinions from the board, especially Dr. Os.

I will post some photos after I can compress them.

Thanks!
Member:
stek

Posted on Monday, Jan 30, 2012 - 11:28 am:

Pics of the hay mentioned above:

hay inside bales

mildew spots (you can see the baling twine in the pic for a sense of scale:

hay mildew spots
Member:
babychop

Posted on Tuesday, Jan 31, 2012 - 10:12 am:

I just happened on this today in an article on what not to feed your horse! Thought immediately of you so here it is:

Question: My hay is only a bit dusty or moldy—is it okay to feed?

Even hay that is a bit moldy can cause big problems.

Answer: Never feed dusty or moldy hay. Even if you wet the hay with water, the horse can breath in enough mold spores to seriously damage its lungs. One winter of feeding moldy hay can turn an athletic riding or driving horse into a horse that few people will want. There is no cure for damaged lungs and drugs can only partially alleviate symptoms. Most horse sports will not allow a horse to compete if drugged.
New Member:
jagd

Posted on Tuesday, Jan 31, 2012 - 11:13 am:

I had similar problems with moldy hay this past year, and after our Vet who publishes a monthly bulletin, specifically mentioned mold and spore infected hay problems, I went out and purchased a steamer, which he also recommended. I steam all my hay now and haven't had any more problems. You see, one of my horses had experienced heaves earlier in the year and I wanted to prevent any additional problems. The steamer is really easy, and the horses love it. I only have 3 horses so it's not that big of a deal. I imagine it could be a problem for greater numbers.

Here is the site I researched and purchased my steamer from:

https://www.haygain.us/
Member:
stek

Posted on Tuesday, Jan 31, 2012 - 11:24 am:

Thanks for your response Andrea. The mildew spots we're seeing are not what one would consider moldy hay by a long shot. After posting, I actually spoke with a couple vets about this who have seen what we're describing. Both have said that it's common in this climate and most people don't think twice about it.

Of course, even a very small amount of dust, mold, mildew etc can cause a reaction in horses that have COPD.

As far as I know we don't have any horses that have COPD in the barn, but to be on the safe side I am setting aside the bales from the outside of the stack that have these teeny tiny mildew spots, however small they are, and feeding them only to my horses who I know don't have any respiratory problems.
Member:
vickiann

Posted on Tuesday, Jan 31, 2012 - 9:46 pm:

This hay steamer sounds great to me!

Can you steam the hay bales and then leave them sit for a day or two before feeding?

About how much does one cost?

One of my horses (my oldest guy) has been coughing recently because some of my hay is "dusty" and it has been causing me some lung and rhinitis problems too.

I do my best to avoid such hay but am picking very carefully through each bale because coastal hay is hard to come by right now, but my nose gets in overload.
Moderator:
DrO

Posted on Wednesday, Feb 1, 2012 - 3:39 pm:

Hello Shannon,
Remember that horses develop COPD in response to exposure to mold dusts. Do you see dust when flakes of the hay are shaken or smell mold. This would sure indicators the hay should not be used. The article associated with this discussion area talks more about this.
DrO
Member:
stek

Posted on Wednesday, Feb 1, 2012 - 4:44 pm:

Thanks for your input Dr O. There is absolutely NO dust or mold present inside the bales, nothing when they are shaken apart. If there were it would be a no-brainer to toss it, at least for me.

We shake all flakes apart when we feed them for all hay just as general farm policy. When I press my face against the flakes and sniff it smells sweet and clean. I can't stress strongly enough how minimal the mildew spots are, I just want to be sure I'm taking every possible precaution.

As I understand it, horses that are sensitive to mold/dust/pollen/etc have essentially an allergic/asthmatic response, and those symptoms are indicative of COPD. From what I could gather from my research and talking to other vets, there is no known cause for COPD, studies point to it possibly being hereditary. But horses that have it will react by showing the classic 'heaving' symptoms when exposed to even very small amounts of irritants. That sensitivity and reaction can get worse over time.

In other words, it's not even dusty hay or a bad environment that causes COPD, but rather a horse that has COPD will have an asthmatic response when presented with irritants he's sensitive to.

Am I understanding that correctly?
New Member:
jagd

Posted on Thursday, Feb 2, 2012 - 10:04 pm:

VickiZ,

Steaming instructions indicate no longer than 12 hours after steaming for any guarantee on spore free hay. My horse was doing the same, but no problems after steaming...and honestly the hay smells so sweet...they can't resist it....
Member:
vickiann

Posted on Thursday, Feb 2, 2012 - 10:55 pm:

Thanks.

Trying to convince my husband that this equipment would be worthwhile.
New Member:
jagd

Posted on Thursday, Feb 2, 2012 - 11:21 pm:

I have mine on a timer so when I go down to the barn in the morning.....my hay is already ready, and the same in the afternoon. So it's not like you've got to go down and hang out at the barn. Once I got into the routine, I don't even notice any real extra work. Best of luck with it.
Member:
vickiann

Posted on Friday, Feb 3, 2012 - 9:14 am:

Thanks! Great idea!
Moderator:
DrO

Posted on Sunday, Feb 5, 2012 - 8:11 pm:

Not exactly Shannon, the most common cause of COPD is chronic exposure to inhaled mold spores and the horse developing an allergy to it. Exposure causes the allergy. It has been hypothesized that horse differ in their sensitivity based on genetics. To read a detailed description of this common problem of horses see HorseAdvice.com » Diseases of Horses » Respiratory System » Heaves & Chronic Obstructive Pulmonary Disease.
DrO
Moderator:
DrO

Posted on Sunday, Feb 5, 2012 - 8:13 pm:

PS I did want to say if that is mildew, it is mold. And while it may not be a big spore former it is indicative of moist conditions where other molds may form. Be sure to continue to critically evaluate your bales for mold spores.
DrO
Member:
stek

Posted on Tuesday, Feb 7, 2012 - 1:45 pm:

Thanks Dr O. The only moisture is the humidity in the air, so I don't know what can be done to stop it. Have seen this in every situation from hay stored in a totally sealed loft with ridge and eave vents, to 3 sided shed, to hay stored in our enclosed but extremely well ventilated barn (current).

We do check all hay carefully as a matter of course.

My confusion about COPD still exists. What other vets have told me is that it is a condition that is most like allergies in humans. This would lead me to believe that a horse either has it genetically or not. I can spend all day every day eating peanuts and petting cats and I'm never going to get a reaction. But my friend who is allergic can't tolerate even a small amount of exposure. Her allergies have always existed, but have gotten worse over time which is what I was thinking was the case with COPD.

Please don't misunderstand my meaning as an intent to justify feeding bad hay, I'm just trying to understand the disease as I don't know much about it.
Member:
babychop

Posted on Tuesday, Feb 7, 2012 - 3:06 pm:

Well Shannon, if this doesn't confuse you more re: allergies I don't know what will: My friend Delsey grew up in Lima Peru literally living on Mangos, she LOVED them, ate them all day long, now? If she even comes near them she puffs up like Martin Short in one of those silly movies. She can't even take one bite out of food that has touched a bit of Mango juice, she is now deathly allergic to Mangos.
Member:
vickiann

Posted on Tuesday, Feb 7, 2012 - 9:23 pm:

Allergies can develop over time and sometimes can come and go in my experience.

Some of them seem to be kind of cumulative like getting bitten by fire ants a few times with the reaction escalating each time.

The part of the mango that causes the biggest problem is the spot that is right there where the stem connects to the fruit.

Mangos are kind of related to poison ivy, I think, and persons who are very allergic to poison ivy are more apt to react to mangos.

I've never been allergic to either but my daughter is highly sensitive to poison ivy and has had a horrible reaction to a mango that took us to the hospital for treatment.
Moderator:
DrO

Posted on Thursday, Feb 9, 2012 - 7:34 am:

Shannon allergies (there are 4 main types) are not a genetic disease. It develops when the immune system is exposed to a foreign large molecule, often a protein, and reacts to it thinking it may be an infection. With continued exposure the immune system learns to overreact to the foreign substance causing disease. The nature of the disease depends on what part of the immune system is reacting.

Almost any horse can develop COPD with continued exposure to high levels of hay mold. What may have some genetic component is the ease with which that allergy develops but while logical this is largely conjectural.
DrO
Member:
stek

Posted on Friday, Feb 10, 2012 - 1:41 pm:

Hmm. I have been doing some research on the web (dangerous I know) and from what I've read allergies are indeed genetic. For example:

https://wupa.wustl.edu/record_archive/1998/01-15-98/4477.html

There is a second component that is unclear; that is the component that causes immune overresponse to the allergen.

Maybe the comparison to allergies is what's not correct for COPD? Though everything I've read describes it as an allergic response.

???
Moderator:
DrO

Posted on Sunday, Feb 12, 2012 - 10:36 am:

Shannon the paper does not say allergies are genetic disorders. It does say if you have certain genetic makeups you are far more likely to develop allergies (see my previous posts). The two are not the same. Take this example. Albinism is a genetic trait. As an albino you are extremely likely to experience sun burn if you expose yourself to strong sun than a non-albino however we don't label sunburn as a genetic disease. Got it?
DrO
Member:
stek

Posted on Monday, Feb 13, 2012 - 3:19 pm:

Got it Dr O, I think we were just mis-communicating on the whole 'genetic disease' versus 'genetic predisposition' thing.
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