From your source where Ethanol by-products are discussed vs. other distillers grain which are safe to feed.
Some ethanol plants offer products termed "modified distillers grains"; however, there are currently no industry guidelines as to what "modified" means. In some cases the distillers grains are partially dried to, for example, 50% dry matter. Sometimes greater or lesser amounts of solubles are added to the distillers grains, or there may be other modifications. These can be very good products to incorporate into dairy cattle diets. However, it is important that the supplier provide accurate composition analysis data, and that the product be consistent from batch to batch.
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Concerns and Potential Problems
with Distillers Grains in Dairy Production
There are several items often cited by dairy producers and nutrition consultants that should be mentioned here (see chapter 10 for greater detail on these issues).
Inconsistency (variability) of product within plants and between plants is frequently mentioned.
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High phosphorus or sulfur content in the DGS usually comes through the solubles. A high phosphorus concentration in DGS usually indicates that more-than-normal amounts of solubles were blended with the distillers grains. Sulfur-containing compounds are often used for controlling pH and cleaning equipment during various stages in the ethanol plant operation, and these compounds often end up in the solubles. While high amounts of sulfur in DGS are not usually a problem, if one is feeding more than 30% DGS that may contain higher-than-normal amounts of sulfur, and this is coupled with high sulfur water or other feeds that are also high in sulfur, the diets may approach the recommended dietary maximum of 0.4% sulfur in total ration dry matter (NRC, 2001).
Again the case study sighted is from 2001 and was "cherry picked" to highlight the good points of feeding distillers grain.
But this time they do mention, and I quote, the " Concerns and Potential Problems " when speaking of "Ethanol" by products.
And they also mentioned the importance of the
"supplier provide accurate composition analysis data, and that the product be consistent from batch to batch " which is not being done even today.
Now read these and remember these are about "ETHANOL" et al by-products which use sulfur to extract alcohol, not other distiller grains that do not use sulfur to extract alcohol.
Check the mineral content to avoid mineral imbalances due to high levels of phosphorus, potassium and sulfur. Of these, possibly the most serious problem is with sulfur, which routinely reaches 0.5 to 0.6 percent and sometimes higher, particularly in the wet product. This may limit the amount which can be used to about 0.5 percent of body weight (dry matter basis). Sulfur content is a particularly worrisome problem in Tennessee because the Tennessee Forage Mineral Survey has shown that sulfur levels typically run at levels high enough to cause problems with cow-calf and forage-based stocker operations. These problems include rough hair coats, depressed growth rate, compromised immune systems (they get sick more easily) and decreased breeding efficiency.
Source: http://www.thebeefsite.com/articles/938/corn-gluten-feed-for-beef-cattle
Considerations for Use
A few cautions about feeding CGF. First, the sulfur (S) concentration of CGF is high relative to the animal's requirement. Sulfur dioxide is added during the wet milling process to aid in the extraction of starch. The added S ends up in the steep liquor which is one of the components of CGF. The sulfur concentration in CGF averages around 0.5% (DM basis), with a range of 0.33 to 0.73%. The S requirement for beef cattle is 0.15 to 0.2% total dietary S. The upper safe limit is 0.4% total dietary S (NRC, 2005). Feeding large amounts of CGF with a high S concentration can lead to S toxicity, resulting in reduced feed intake and possibly death. A specific disorder associated with excess S is polioencephalomalacia (PEM or commonly referred to as "brainers"; Niles et al., 2000). This disorder affects the nervous system resulting in blindness, incoordination, and seizures (Gould, 1998). Excess S in the diet can also increase the risk of a copper deficiency. Copper is an essential trace mineral important for growth, immunity, and other metabolic functions (NRC, 2005). The potential risk of high S in the total diet could limit the amount of CGF than can be used in a feeding program.
Source: http://www.thebeefsite.com/articles/1449/feeding-corn-gluten-to-beef-cattlesup1-sup
My point is this:
There has been for many many years distillers grains out there that have been safe for human as well as animal consumption.
I have eaten it and feed it to my livestock and never had a problem with it, until "now".
And I define "now" as the beginning of the use of sulfur to increase productivity in an attempt to produce a ( P ) profit.
If you are old enough to remember the days when alcohol was the only antifreeze for your vehicle ( pre early 60s ), the distillers grain was feed to livestock by the tons and there was never a problem nor was there any warning associated with feeding it.
So you see, I am not anti distillers grain, just anti- distillers grain with ( S ) sulfur added that is delivered without an analysis sheet.
And I am against custom mixed feeds being sold in bulk or bag that does not contain the sulfur content on the bill of laden or tag on the bag.
SL