Selenium guidelines anyone?

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sunnyblueskies

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Where are the mineral smart people? I have a question.

We usually give free choice salt blocks to our herd. They are Trace Mineral with Selenium. Our area soil is selenium deficient.

Last calving we had a few problem heifers and our Vet suggested putting out free choice molasses/mineral tubs like 2:1 or 3:1.

Here comes my question. The label on these tubs warns not to feed these tubs together with other feeds/minerals/salts which contain selenium.
First of all, how would one even measure selenium intake when it's free choice and lickable.
And second what is a number guideline of how much an adult cow can take on selenium and what is too much?
What are the negative side effects of giving too much selenium?

It's no big deal to switch to different salt without selenium, but I just wondered after seeing the warning on the label.
 
Where are the mineral smart people? I have a question.

We usually give free choice salt blocks to our herd. They are Trace Mineral with Selenium. Our area soil is selenium deficient.

Last calving we had a few problem heifers and our Vet suggested putting out free choice molasses/mineral tubs like 2:1 or 3:1.

Here comes my question. The label on these tubs warns not to feed these tubs together with other feeds/minerals/salts which contain selenium.
First of all, how would one even measure selenium intake when it's free choice and lickable.
And second what is a number guideline of how much an adult cow can take on selenium and what is too much?
What are the negative side effects of giving too much selenium?

It's no big deal to switch to different salt without selenium, but I just wondered after seeing the warning on the label.
I'm sure there is a more technical answer, and this is anecdotal, but my winter mineral has the same warning that your tubs have regarding selenium. But I continue giving the TM salt blocks while feeding the mineral and have seen no adverse affects.
If your area were known to be high in selenium then you would have more to be concerned about I think.
 
We're not low in selenium, so can't help you there. But we contacted the K-State Extension office (luckily in town) and talked with our vet to figure out an appropriate (loose) mineral program for our area. Vet contacts me when it's time to switch to mineral with CTC prior to the start of tick season. Do you have any resources available like that in your area?
 
I would be very skeptical of anyone who would claim to be able to answer that question very specifically. There are a lot of unknowns around trace minerals. Too little is bad, too much is bad, and somewhere in between is good, but it's very difficult to figure out the exact ranges even in research settings, let alone cattle on the farm.

Anecdotally, I know people who have fed over the recommended levels of selenium with no problems. Where I've seen farmers really get into trouble is with injectable selenium products. Mineral toxicities usually have vague symptoms like weight loss and sudden death, and many people unwittingly confuse them with mineral deficiencies.

The only real way to objectively evaluate your mineral program is by testing your cattle, ideally by submitting a liver sample to a lab. Some vets will do liver biopsies on live cattle, but many won't have the right equipment and there is some risk involved. It's very easy to do with a dead cow. If you ever have an otherwise healthy adult cow die suddenly from something that wouldn't impact her mineral status (i.e. broken leg, choke, lightning strike, etc.), grab a chunk of liver and send it off.
 
You might want to read "From the Feed Trough by Woody Lane" He does talk some about minerals.

Although for me it left more questions than it did answer, but it did give some one insights I didn't know before.
 
We're not low in selenium, so can't help you there. But we contacted the K-State Extension office (luckily in town) and talked with our vet to figure out an appropriate (loose) mineral program for our area. Vet contacts me when it's time to switch to mineral with CTC prior to the start of tick season. Do you have any resources available like that in your area?
It was the vet who suggested giving those specific tubs to our cows in the last trimester because of the difficulties some heifers had last spring. I just didn't see the 'warning label' until I purchased the tubs and the vet never brought anything up about 'watch out of this' or 'watch out for that' when she suggested them.
 
Anecdotally, I know people who have fed over the recommended levels of selenium with no problems. Where I've seen farmers really get into trouble is with injectable selenium products. Mineral toxicities usually have vague symptoms like weight loss and sudden death, and many people unwittingly confuse them with mineral deficiencies.
So it's more a thing of which way the cattle receives the mineral?
Ingested orally a lot may pass through the digestive system, or the digestive system will only absorb a certain amount. But if it is given directly into the blood it may cause toxicity.
That makes sense.
 
You might want to read "From the Feed Trough by Woody Lane" He does talk some about minerals.

Although for me it left more questions than it did answer, but it did give some one insights I didn't know before.
I'm not sure if I want more confusion and unanswered questions.
But thank you for mentioning it.
 
Selenium is FDA regulated because some areas have too much SE. "MOST" of US is SE deficient. Cornell asked to use my herd to do some testing for SE. We ended up having to double SE in our mineral (which at the time I had a company custom making our mineral). Cornell actually tried to find the toxic level to kill an animal and could not kill one with OD of SE.
SE is extremely important for pregnancies and calving. Low levels causes open cows, causes long labors and also causes retained placentas. Another main problem is White Muscle Disease from low SE. Newborn calves can be "dumb suckers" - meaning they don't have the ability to suckle. Low SE (WMD) affects large muscles - like the legs, heart and tongue.
Now, from everything I have been told by vets, nutritionists and Cornell - there is enough trace mineral (including SE) in a salt block to satisfy the needs of ONE cow - if she ate the whole block in ONE day. It is false security thinking you are providing the trace minerals with a "mineral salt block". I'm not saying it is harmful. Just wasting your money.
I feed BioZyme Concept Aid mineral.
Lack of mineral is difficult to "see" - and same with the proper dose of mineral - but, long term, your cattle should breed better, calve better. Your vet was being subtle "suggesting" increasing SE intake w/ a tub. When in doubt, you are better off giving a shot of MuSe or Multimin90. Excellent products give 30 days prior to breeding.
No, I am not a vet or a nutritionist - just 50+ years of working with vets & nutritionists.
 
Woody Lane... man, I hadn't heard that name in a couple of decades. He used to be active on 'Graze-L', one of the early management-intensive grazing email discussion groups, based out of NZ...
 
The soil here is very selenium deficient. The Milkyway feed store owner told me there is not enough selenium in those yellow selenium salt blocks for cattle. He advised Purina Wild and Rain. The cows eat what they need of the salt and it doses them with the right amount of selenium as well as magnesium and other minerals. Magnesium is what cows really need here when the grass is green and growing. It is great stuff. It does not blow out of the box and rain does not dissolve it. My cows each ate 1/2 lb a day at first, now they are eating less.
 
I would be very skeptical of anyone who would claim to be able to answer that question very specifically. There are a lot of unknowns around trace minerals. Too little is bad, too much is bad, and somewhere in between is good, but it's very difficult to figure out the exact ranges even in research settings, let alone cattle on the farm.

Anecdotally, I know people who have fed over the recommended levels of selenium with no problems. Where I've seen farmers really get into trouble is with injectable selenium products. Mineral toxicities usually have vague symptoms like weight loss and sudden death, and many people unwittingly confuse them with mineral deficiencies.

The only real way to objectively evaluate your mineral program is by testing your cattle, ideally by submitting a liver sample to a lab. Some vets will do liver biopsies on live cattle, but many won't have the right equipment and there is some risk involved. It's very easy to do with a dead cow. If you ever have an otherwise healthy adult cow die suddenly from something that wouldn't impact her mineral status (i.e. broken leg, choke, lightning strike, etc.), grab a chunk of liver and send it off.
Nutritionist here. Someone else hinted at the reason later in the thread. The reason is Se is regulated by the US government which says cattle cannot consume more than 3 mg of Se/h/d or 0.3 ppm on a dietary basis. The label is basically saying "hey don't feed any more selenium or what you are doing is technically illegal". If you need more selenium move to a mineral that uses a selenium yeast. Should be about 2x as available, same concept as organic copper & zinc. So while you technically won't be feed more selenium they will absorb twice as much. If you did feed two sources of selenium & went over the government regulation most likely you will be fine. I only see selenium toxicity in specific areas of the country that have really high levels in the soil (like South Dakota).
 
The reason is Se is regulated by the US government which says cattle cannot consume more than 3 mg of Se/h/d or 0.3 ppm on a dietary basis. The label is basically saying "hey don't feed any more selenium or what you are doing is technically illegal".
That's the first time I hear about anything like that. Granted I'm in Canada and don't know if such a 'rule' exists here too, but I don't understand the reasoning behind having or legislating such a law.
Does the Government have to stick their nose into what our cows eat too?
 
This is regulatory guidance, fwiw

People take for granted that feed they buy is safe and labeled accurately. Regulation and oversight makes that happen. I've seen a feed mill go from "we don't think it's our problem" to "how much money will make it right?" pretty quickly after a phone call to DATCP.
 
Well, that isn't quite correct. The government dictates how much SE (3 mg,) is allowed to be put in a product for general sale. They do not regulate a product made for an individual. Our local mill made our custom blend mineral with 9 MG SE.
Also, we injected SE prior to calving and prior to breeding. There is no law dictating what/how much SE we give.
It does reg how much is in a product sold to the public.
 
Well, that isn't quite correct. The government dictates how much SE (3 mg,) is allowed to be put in a product for general sale. They do not regulate a product made for an individual. Our local mill made our custom blend mineral with 9 MG SE.
Also, we injected SE prior to calving and prior to breeding. There is no law dictating what/how much SE we give.
It does reg how much is in a product sold to the public.
The US regulations cover national products and custom products. Any products that's labeled intake exceeds 3mg Se/h/d would be illegal. Per head per day is the key here. You have to take the ppm (same as mg/kg) then multiple by the labeled intake (in kilograms not pounds or ounces) that number should be less than 3. Lots of 4 ounce national products I see here Se level is typically 20-26 ppm Se. Multiple that by labeled intake (0.113kg) and you get right about 3mg. If your mineral is 9ppm and labeled at 4oz/h/d they would only be getting 1 mg of Se/h/d.
 
That's the first time I hear about anything like that. Granted I'm in Canada and don't know if such a 'rule' exists here too, but I don't understand the reasoning behind having or legislating such a law.
Does the Government have to stick their nose into what our cows eat too?
I thought Trudeau stuck his nose into everything?
 
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