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Problems with moldy hay

From: Kelly

I was recently at a friend's barn and he was complaining about how his hay went moldy quick. He thinks it was moldy when he got it but can't prove it. What is the PC way of either getting the moldy hay replaced or getting your money back? Is there a way to prevent mold in the hay? He is worried his horses will die if they eat a little amount of the moldy hay.

Any advice is great. Thank you, Kelly

Hi Kelly! First, your friend is correct, and he is absolutely right to be worried - moldy hay can cause permanent lung damage to horses, and some molds also contain toxins. Horses should NEVER be fed moldy hay. Even "a little" mold can be disastrous. He needs to go through his load of hay and discard all of the bales that are obviously moldy; then he'll have to keep a close eye on the remaining bales. Whenever he feeds his horses he'll need to check the hay, flake by flake, as he distributes it. He probably does this already, without thinking about it - checking hay is automatic behaviour for horsemen.

Whether your friend can return any of his hay at this point will depend on what sort of relationship he has with the seller. Normally, if a barn owner orders a load of hay and finds some moldy bales when the hay is being delivered, the barn owner would simply have the seller put those bales aside. When all of the good bales have been stacked, the seller can put the moldy ones back on the trailer and take them away, and the barn owner can pay for the good ones. If more hay is needed, the seller may be able to come back with a second, smaller load.

Once someone has accepted a load of hay, it's a bit trickier to send it back. If your friend was away from the barn on the day that the hay was delivered (that's never a good idea, by the way), and if he believes that he was given a load of moldy hay, the correct thing for him to do would have been to ring up the seller immediately and ask him to come back and pick up the hay.

Preventing mold in hay requires good "hay management" on the part of the hay farmer and the buyer. It begins with the person who grows, cuts, and bales the hay. Mold WILL appear in hay that was too wet when it was baled, but baling hay at just the right degree of humidity isn't an easy task. If you ever put up your own hay, you'll discover just how difficult it can be to cut it at the right time - the hay has to be in the right stage to cut, AND the weather has to be dry and clear and likely to stay that way until the hay has been baled and stored. The hay needs to have time to dry in the field before it is baled, and then it needs to be stored in a dry place with good ventilation. It sounds easy, doesn't it? But we all know how unreliable weather forecasts can be, and how quickly weather can change.

Some hay farmers use preservatives or mold inhibitors on their hay to help prevent mold. Some of these, such as proprionic acid, are safe for horses. They are usually applied during the baling process - your friend can ask his supplier about this.

Hay can also mold AFTER it's been delivered to the buyer, and sometimes the fault is the buyer's. If your friend stored his hay where it was in direct contact with the ground or where it was unprotected from rain or snow, then he will need to change his hay-storing arrangements before his next load of hay is delivered.Storing hay directly on the ground will allow moisture to penetrate the bales; storing hay where it can be rained on will also allow moisture to penetrate the bales. Hay will keep best if it's stored indoors with a layer or two of wooden pallets between the ground and the bottom layer of bales. Hay for horses needs to be very clean - meaning no trash, no dust, and above all, NO MOLD. Keeping hay dry and allowing good air circulation will help keep clean hay clean.

It doesn't take much mold to cause horses to develop permanent lung damage - that's why horse hay can never be dusty or moldy, not even "just a little bit" dusty or moldy.

Testing hay for a degree of moldiness isn't easy or practical; horse owners need to train themselves to pay close attention to their hay and notice signs of mold - from musty odour to visible mold to obvious (heavy) mold. NO degree of mold can be tolerated if you're using the hay for horses. Once a horse develops lung damage from moldy or dusty hay, it may become sensitized to ALL hay - not just moldy hay - and require major changes in management for the rest of its life. It's not always easy to keep a horse outdoors 24/7 or to find an alternate source of roughage.

Round bales always present more of a risk to horses, but if the bales are stored indoors and you have enough horses to clean up a round bale in two or three days, it's often possible to use round bales for horses. If you have only a few horses, and a bale placed in a field or paddock would be there for a week before it was consumed, then the situation is different and the hay would be likely to develop mold. Round bales don't represent much of a savings if you have to go out every day and peel off and dispose of the outer layer of hay. There's a huge amount of waste involved - but it IS better to waste hay than to make horses ill.

If your friend needs to dispose of moldy hay, he might be able to make an exchange with someone who raises beef or dairy cattle. This doesn't mean that your friend will just be passing on his problem to someone else; ruminants have a much higher tolerance for mold in hay. Horses can starve, die, or both from eating hay that would allow dairy or beef cattle to thrive. When you're wondering whether to feed hay to horses, the question you should ask yourself is "Is there any mold at all?" When you're wondering whether to feed hay to cattle, the only question is "Will they eat it?" For cattle, the issue isn't safety, it's palatability.

One more thought: When you're checking your hay, don't assume that "no musty smell" means "no mold." Although a musty smell is definitely an indication of mold in hay, some hay can be moldy and smell sweet - not sweet like fresh, clean hay, but almost "candy-store" sweet. This happens when moist heat - the conditions that lead to mold - cause the sugars in hay to "cook" or caramelize, so be sure that you always make a visual inspection of the flakes you're handing out.

I wish your friend good luck with his hay situation. How fortunate for his horses that he was wise enough to know that they should never be given moldy hay!


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