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market-farming - RE: [Market-farming] Poultry manure

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  • From: "Rick Williams" <mrfarm AT frontiernet.net>
  • To: <market-farming AT lists.ibiblio.org>
  • Subject: RE: [Market-farming] Poultry manure
  • Date: Sun, 2 Feb 2003 20:34:43 -0600

> Rick - there are quite valid studies done on both hormones and antibiotics
> in the water systems that aren't being taken out by water treatment
> facilities and have the potential to cause quite a lot of problems for
> anyone drinking the water in terms of antibiotic resistance and
> estrogen in
> young females and males.

Yes, in water and by that I mean primarily surface water. I think there is
some confusion here with poultry. They do give off natural hormones (imagine
that, for all you chemically sensitive folks) but so do ALL living things.
But we were talking about manure issues here. And specifically added
hormones and antibiotics. I really find it hard to believe that with all the
stuff we humans use, that we don't understand that we will see all sorts of
chemicals in surface water. But is this coming primarily from farms? Most is
flushed down the toilet from the humans who are using the drugs, hormones,
antibiotics, household chemicals, etc. Farm run off is a problem but with
the new regulations for CAFO's, the amount of P is restricted and that means
that you can not put the manure on as thickly as was once permitted.

But that gets us away from the composted manure. Some sources suggest that
composting manure doesn't break down some of the hormones as well as
spreading it but then it also may be due to the spread manure running off
and therefore making the hormone portion look as if it has dissipated.

Here is one comment that outlines that but also points out:

"He says that he'd wanted to compare feedlots that use hormones and those
that don't, but he couldn't find any operations that don't take advantage of
the drugs. Moreover, because Soto has not yet identified the particular
steroids in down-stream waters, Guillette notes, "we can't rule out that
these effects are due to natural androgens and estrogens in manure." Even
untreated cattle, horses, and chickens excrete natural estrogens,
testosterone, and other steroids"
http://www.sciencenews.org/20020105/bob13.asp

Another view is the opposite which claims that the composting does degrade
the hormones.

"Livestock naturally excrete large amounts of estrogen and testosterone,
hormones that can harm crops and wildlife when farmers use manure as
fertilizer (SN: 7/15/95, p. 44). A study now shows that farmers can rid
chicken manure of much of this unwanted hormonal baggage by composting the
wastes."
http://www.phschool.com/science/science_news/articles/composting_cuts_manure
..html

> Unless someone could say with certainty that antibiotics and hormones in a
> manure have no effect on our produce (or those eating the
> produce) why take
> a chance. Aren't we doing enough damage as it is?
>
It is most unlikely that properly composted manures would have high levels
of hormones, other than natural ones that are literally everywhere. In fact,
some folks push this from the other side and claim that the fresh manures
(such as horse) are better for plants compared to the less active old
compost which doesn't have the hormones the plants need. Are they right?
More study would need to be done to know for sure.

> To call this kind of concern extremism has a "Rush" twang to it.

I view it as extreme with the hormone issue. There is an ARS experiment
being done but the results will not be available for at least another year:
http://www.nps.ars.usda.gov/projects/projects.htm?accession=404016

McGill U. has this comment: "Manure plus - Manure benefits crops in a
multitude of indirect ways. It feeds the tons of soil organisms beneath each
acre, such as earthworms, bacteria, insects, nematodes, protozoa and fungi.
Plants benefit from vitamins, hormones, and, perhaps, other growth promoting
substances yet to be discovered, dubbed by one researchers as "fecal
factors".

The main point that I was making is putting things into perspective. The
tiny amount of hormone in the mini-tab that is implanted in the livestock
ear, then a very small amount of that may get into the bloodstream, then a
part of that gets in the manure to be excreted, some broken down, some
actually normal hormones then the remaining amount in the manure either
breaks down or remains until applied on the soil, which further breaks down
and how much could even be absorbed by the plant? It is so tiny compared to
say one birth control pill which would be what, a thousand or a million
times stronger per use?

Now antibiotics are a different story. There we need to eventually phase out
any routine feeding of human theraputic antibiotics. There is some
compelling evidence in terms of pass through and even uptake by plants as
you mentioned.
Here is a source, but I can not vouch for its reliability.

http://www.healthsentinel.com/News/ExcretedAntibiotics.htm

Sincerely,

Rick Williams








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