Toxic hay preservatives

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Post   » Wed Apr 03, 2002 4:27 pm

Today I was informed by a pet store employee that care should be taken when storing alfalfa hay. She said to keep it away from heat sources as it gives off a toxic substance if heated.

I had never heard of this and knowing the general reputation of pet store employees (totally clueless) I thought I should check it out. Seems she was at least partially right.

Some hay, not just alfalfa, is treated with preservatives to prevent spoilage. Two types of preservative are commonly used: ammonia based organic acids and their salts, and microbial additives. The most common organic acids used are: propionic acid, a liquid, and anhydrous ammonia, a gas. It seems in using ammonia it´s very important not to exceed the application rate of 1% of dry weight because of the toxicity risk. I found this somewhat alarming:

Applying more than 1% ammonia to high quality forages can result in the formation of an unknown toxic compound. Animals consuming ammoniated high quality forage often exhibit hyperexcitability followed by death. The toxin is transferred into milk, so nursing calves and lambs also are susceptible to the toxin. HIGH QUALITY HAY MUST NOT BE TREATED WITH MORE THAN 1% AMMONIA (DRY MATTER BASIS).

More cause for concern:

Disadvantages of Using Hay Preservatives

1. Propionic acid is corrosive and can damage machines and injure workers.
2. Anhydrous ammonia is difficult to apply and is a hazardous chemical.

This information is from the Ohio State University Extension:

This leads me to wonder how much hay is treated with preservatives and whether this has any relation to some of the "mystery" ailments our pets suffer.

Apparently fresh cut alfalfa is sometimes treated with chemical "drying agents" too. Don´t know if I even want to go there.

Last edited by pigpal on Wed Apr 03, 2002 4:29 pm, edited 1 time in total.


Post   » Wed Apr 03, 2002 4:44 pm

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Post   » Wed Apr 03, 2002 6:02 pm

That is pretty interesting. I had never heard of hay being treated. Maybe someone would like to write Oxbowhay and the other online hay company (American Pet Diner?) to see if their hay is ever treated with anything.


Post   » Wed Apr 03, 2002 7:21 pm

I just emailed Oxbow, since I was getting ready to place an order, and I would like an answer before I do so! I will share their reply when (if) I receive it.


Post   » Wed Apr 03, 2002 8:58 pm

It seems these preservatives are USDA and FDA approved and are not supposed to be harmful, when applied as directed.


Post   » Wed Apr 03, 2002 9:16 pm

Wow! Interresting!

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Post   » Wed Apr 03, 2002 9:38 pm

I have never heard of this! Very interesting--is it done in the field? I suppose I should read the links to find out.


Post   » Thu Apr 04, 2002 1:37 pm

I just received the response from Oxbow. Dawn Hromanik wrote the response, and mentioned that if anyone else would care to email she would be happy to answer everyone.

Dawn says that they do not use any chemicals on their hay. However, she finds it somewhat ironic that we are worried about it, while some rabbit people are actually encouraging it! In her words: "they feel it will decrease any mycotoxin
problems." She goes on to say that properly dried and baled hay won´t have a mycotoxin problem even without the use of preservative chemicals.

Since I neglected to get permission to repost her email in its entirety publicly (I know, I´m sorry!) I probably shouldn´t. However, if anyone wants a copy of the email, I can forward it to you. (That´s allowed, right?)

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Post   » Thu Apr 04, 2002 5:27 pm

Yes it is. I´ll bet she wouldn´t mind if you printed it -- just email her for permission. It might save her some work down the line answering the same question. I´ll bet she wouldn´t mind being asked.


Post   » Thu Apr 04, 2002 6:22 pm

Could you forward it to me? I´m pretty sure my profile lists my email address.


Post   » Fri Apr 05, 2002 10:19 am

Dawn just gave me permission to post her email reply:

We do not use any chemicals or preservatives in any of our hay. I am
aware that some producers do have access to this product and it is used
in areas of that receive a lot of moisture and they have problems with
getting hay "put up" in a timely fashion before it throughly dries.

It is ironic however because some rabbit owners are wanting to increase
the use of this product as they feel it will decrease any mycotoxin
problems. The bigger picture and concern is that you make sure that you
dry your hay throughly before it is baled and you will not have a
problem with spoilage, heating, or mycotoxins.

Be assured that our hay is not treated in any way with any chemicals or
preservatives. If you or anyone else has any questions please feel free
to call me or anyone else can email me as well.

Best Regards,
Dawn Hromanik

Director of Nutrition and Product Development
Oxbow Pet Products
"Specializing in Herbivore Nutrition and Supportive Care"

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Post   » Fri Apr 05, 2002 1:07 pm

What are "mycotoxin problems"?

Jin, thanks for sharing the e-mail.


Post   » Fri Apr 05, 2002 10:04 pm

When hay is cut the weather should ideally be dry for a few days, so the hay can dry in the sun before being baled and stacked. Unfortunately some areas have unpredictable weather and a rain shower at hay-making time can ruin an entire cutting. If hay is cut and baled when it´s damp, heat builds up inside the bale and molds form. Some of those molds and fungi are poisonous, that´s what mycotoxins are. At least that´s my understanding of it. I´m sure someone will correct me if I´m mistaken.

The preservatives kill the molds and fungi, the chemical dessicants dry out the hay so the molds don´t form.

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Post   » Sat Apr 06, 2002 3:54 pm

Thank you, Pigpal.

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