SELENIUM, WET DISTILLERS GRAIN AND CAMELINA by Mike Mehren Ph.D.

SELENIUM, WET DISTILLERS GRAIN AND CAMELINA
BY MIKE MEHREN

The Oregon Feed and Grain held their annual convention this past month. The subjects that the speakers addressed were very timely, not only for the feed industry, but also for those feeding livestock. The following is a brief summary of those topics.

Can you believe that selenium toxicity was diagnosed and confirmed in Oregon? That threw me for a loop. I’ve only seen one case of this in the past 30 years, and that happened when the cattle were fed 1 lb/hd/day rather than 0.1 lb/hd/day...a tenfold excess. This amounted to 30 milligrams a day rather than 3. During the investigation
of livestock deaths and poor performance, the researchers tested some grains and
supplements. These yielded some very surprising results.

Product	Expected	Found	% of Expected
	....parts per million..
Whole Corn (midwest)	0.1	0.153	153
Whole Corn (midwest)	0.1	0.265	265
Oat Pellets	0.1	0.174	174
Soybean Meal	0.1	0.451	451
Soybean Meal	0.1	0.781	781
Textured Grain Mix	0.1	0.544	544
Mono Dicalcium Phosphate	0.1	1.440	1440
Selenium 90 Salt Block	90	40	8 45

(Adapted from Chronic Selenium Toxicosis in Oregon Swine, E.T. Estill, 2008)

These figures show that livestock being fed these feeds would get quite a bit of selenium from the feed itself. The maximum amount of selenium allowable in the diet of beef cattle is 0.3 ppm or 3 milligrams daily. Except for the mono-dical; I suspect that most of the selenium in the feeds is in the ‘organic form’, which means it would be quite a bit more available to the animal than sodium selenite. Sodium selenite is the source of selenium most commonly added to livestock feeds. We certainly need more information about the selenium content of minerals, grain, and vegetable proteins that are being fed in Oregon. Fortunately for those in the cow calf and stocker
sectors of the cattle industry, none of these feeds is fed in an amount that would be toxic under normal circumstances. The groups of animals that might be in danger would be bulls where a ranch is buying a concentrate to compliment their own hay
or hay and silage. This feed is fed at a range of 10-20 lb/hd/day, so excess selenium is possible. The other group would be 4H and FFA students buying a ‘show steer’ feed that is the complete diet other than a couple of pounds of hay. You could make a case for a 12-12 mineral (this has 12% calcium and 12% phosphorus) made with mono-dicalcium phosphate as the primary source of phosphorus with the maximum amount of added selenium, would potentially provide enough selenium to be toxic when fed for an extended length of time. This would be especially true, if you happen to run cattle in one of those areas of the Northwest where forage has adequate selenium. I use the Olsen Biochem Lab, Box 2170, South Dakota State Univ. Brooking, SD 57007 for selenium testing. The phone number is 605-688-6171.

This particular incident involved pigs, but that doesn’t mean it couldn’t have been calves or animals in a feedlot. One new feed that we use in the beef and dairy industry is wet distillers grain with solubles. Remember that once the sugars and starch are removed the remaining nutrients are concentrated. For instance, corn has approximately 10% crude protein, while wet DGS has about 30% protein; a 3 to 1 concentration. We also
know that sulfur is concentrated in wet DGS and is something that nutritionists pay attention to, because excess sulfur can lead to poor appetite, performance, and feed efficiency. It is also associated with ‘brainer’ cattle. This leads me to the conclusion that selenium could also be concentrated. I have no tests that confirm this at present. Most nutritionists formulating diets for livestock in the Pacific Northwest assume that little if any selenium will be present in the diet. This is probably true for forages grown locally. Feed manufacturers use soybean meal and other vegetable proteins in making a protein supplement. By products such as dry corn distillers with solubles, grain screenings, and wheat midds are used as a carrier in mineral supplements. It is quite possible that some supplements have much higher levels of selenium than the amount claimed on the feed label.

I don’t mean to pick on wet distillers grain with solubles, because it is an excellent feed for cattle. However, an inspection by the Oregon Dept. of Agriculture found that
unapproved antibiotics were being added at a plant. The antibiotics were used to stop fermentation. This means that the feed could not be fed to beef cattle. When an approved antibiotic is used, the feed is allowable as livestock feed. This requires testing to insure that there are no unsafe residues remaining in the feed. This was a case of lack of knowledge rather than disobeying the law intentionally. One specific antibiotic is allowed for this purpose. Cattlemen raising ‘natural’ beef would not be allowed to feed wet distillers since a legal antibiotic is used in the manufacture of that ingredient.

We were introduced to a dryland oilseed crop named camelina that is new to the Pacific Northwest. It is a plant in the mustard family that seems to be quite resistant to drought and frost as well as disease. It contains 30-40% oil that can be used for biodiesel. After it is crushed the residual meal has about 12-14% oil and 34% protein. The nutritional characteristics are quite similar to canola. Hopefully the resultant meal will be available as a protein supplement for cattle. It should be noted that it is NOT allowed as livestock feed right now. The FDA is studying it to make certain that it is not harmful to livestock and that after the animals eat it, the meat is safe for our consumption. Preliminary research conducted by scientists at Montana State Univ. and in Ireland have compared feed intake and production of beef cattle when fed soybean meal or camelina. So far the studies look promising. Feedlot cattle performed well when fed varying levels of camelina in place of corn and soybean meal. Beef cows were fed camelina meal as a protein supplement to low quality forage and no problems were observed. I was shocked at the lack of livestock feeding information available. This is a very old variety of plant, but apparently it is just now being considered as a livestock feed. Toxic compounds have

been detected. These are similar to those found in rape and other members of the mustard family. It is possible that cattle will only tolerate a certain amount of the camelina meal. Cottonseed meal is a very well accepted protein, and was the primary source of supplemental protein in the Northwest until canola meal replaced it due to cost. Cottonseed meal also has a toxic component that limits the amount that can be fed to cattle.

We will undoubtedly feed byproducts and plant products that we have never fed before due to the huge increase in feed prices. Learn all that you can about a new feed before you present it to your animals. First, make sure that it’s safe and legal. The last thing you want to do is have your animal go to slaughter and have it rejected. Next, find out the nutrient content by having it tested at a feed lab. Finally, introduce it slowly to find out if the animals will eat it.

Michael J. Mehren, Ph.D. is a livestock nutritionist who took one for the team by attending the Oregon Feed and Grain Assoc. convention in beautiful Seaside. He can be contacted by Email at mehrens@eotnet.net.