Copper Poisoning and Copper Deficiency in Sheep

by Ulf Kintzel
Articles warning of copper poisoning in sheep appear frequently in various publications. This leads people often to believe that sheep should have no copper in their diet. However, copper is essential for a sheep to even exist. So how likely is copper poisoning?
Let’s examine why sheep are more likely to get copper poisoning than other species that are more tolerant of this element such as goats. Simply stated, sheep have a greater difficulty disposing of excess copper than other species of animals. If there is an excess of copper in a sheep’s diet, it is stored in the liver. It is then only slowly disposed by the sheep’s liver. Over time excess copper will accumulate. When the animal is stressed, the copper is released all at ones into the blood stream. This is called chronic copper poisoning and is more common than acute copper poisoning. Death is certain when a sheep shows symptoms. Treatment options exist theoretically speaking but are not practical or feasible in real life. However, chronic copper poisoning does not occur as a widespread outbreak. Only one or at the most a few individual animals will die at any one time.
Because of the sensitivity to copper, feed stuff and minerals for sheep have no copper added, which is often confused with not containing any copper. Most feed stuff, be it forage or be it grains, does contain copper. In fact, sheep need copper for very important biological functions. For instance, the development of the central nervous system requires copper. That means there is also the real possibility of copper deficiency. This article makes the attempt of putting both copper poisoning and copper deficiency in perspective.
About twenty years ago, I used to feed minerals designed for cattle that had copper added. I did so because minerals designed for sheep were unavailable to me at that time or at least not obtainable at a reasonable price. I did that for a few years without any negative impact to my flock of Texel sheep, which I ran at that time. Finally, I got a hold of a representative of a feed supply company and was now able to receive minerals for sheep. The same year, I pastured my sheep most of the winter on residue on heavily limed hayfields. Lambing came around in late winter and I had an unusual number of still born lambs. Many of the lambs that were born alive had a retarded suckling reflex and died despite of all the help shortly after birth. I had epidemic-like losses. The diagnosis was copper deficiency. The limed fields had aided the problem since lime reduces the amount of available copper in plants.

Copper is an essential element for proper development of sheep.

Copper is an essential element for proper development of sheep.

I read up on the subject of copper deficiency and ever since then I feed free-choice minerals with added copper right around the time when my ewes are 100 days into gestation. That is when the central nervous system of the un-born lambs develop and copper is essential for it.
Let’s also remember that copper sulfate used to be used as a dewormer for sheep and indeed I use it from time to time as a dewormer still by throwing once in a while a small handful into the water trough.
Over the years following the incident of copper deficiency, I had gotten lax about added copper in minerals or salt with added trace minerals (which includes copper) and used it indiscriminately. It caught up with me. One year I lost one sheep in the fall and the following winter another due to chronic copper poisoning. Since I didn’t want to risk the health of my expensive new rams I discontinued the liberal use of minerals with added copper for a while. Instead, I deliberately use minerals or salt with added copper at certain time intervals, especially at the time when my ewes are right around the 100 day mark during pregnancy.
A word of caution: my experience is limited to minerals and salt with added copper. I don’t know what the effect would be if one were to feed a grain mixture with added copper. I don’t feed any grain since I have been grass-fed for many years. I would suspect that the effect would be much more pronounced simply because of the greater amount of grain consumed compared to minerals and therefore also a far greater amount of consumed copper. Any grains that are being fed already contain copper, which makes in my view copper deficiency in grain-fed sheep highly unlikely.
Over the years, I came to this conclusion: Many articles have been written about copper poisoning in sheep that warn time and time again against feeding feed and minerals with added copper. They are warranted given a sheep’s higher sensitivity to copper when compared to other animals like goats or cattle. Very little is being said about copper deficiency. Copper deficiency is a real possibility in grass-fed sheep, especially when limed fields or moorland pastures are grazed, which are often low in available copper. While copper poisoning often only claimed a sheep or two when it occurred at my farm, copper deficiency was devastating when it happened. I have adjusted my schedule of feeding minerals with added copper to avoid such devastating loss due to copper deficiency.
Ulf owns and operates White Clover Sheep Farm and breeds and raises grass-fed White Dorper Sheep without any grain feeding and offers breeding stock suitable for grazing. He is a native of Germany and lives in the US since 1995. He farms in the Finger Lakes area in upstate New York. His website address is He can be reached by e-mail at or by phone at 585-554-3313.

Avatar of Tara Hammonds

Tara Hammonds


  1. Avatar of Luke Luke on March 4, 2017 at 10:53 pm

    Do you think it is safe to supplement with the Purina Accuration protein block which contains 21 ppm of copper? A ewe will probably not eat 1 lb. of the Accuration per day.

  2. Avatar of Andrea lollis Andrea lollis on December 30, 2017 at 8:26 pm

    My lamb ate a copper penny! Do you think he will be okay?

    • Avatar of Tom Tom on November 24, 2019 at 6:21 am

      The penny would most likely pass through a sheep system before much of the copper surface corrodes. For some reason it does not, modern pennies are mostly zinc which can help counter the effects of copper poisoning.

  3. Avatar of samg samg on May 18, 2018 at 2:34 pm

    Andrea, did the lamb die?

  4. Avatar of Dave Dave on August 2, 2018 at 11:00 am

    Thanks. I’m just starting out with sheep and I’ve wondered about the “”No Copper” hysteria. It just did not make sense to me that it was, “no copper ever” but that is what everyone seemed to be saying. Now I won’t freak out if they get out and take a couple licks on my cattle’s brown mineral block because it has some copper in it.
    Are there any easy ways to tell if your sheep’s copper levels are in the zone? Are there any early warning signs of copper deficiency or copper poisoning?

    • klr235 on August 7, 2018 at 11:41 am

      Hi Dave,
      I’m glad to hear that this article was helpful! Regarding your questions about testing your sheep’s copper levels, I would recommend reaching out to the author of the article, Ulf Kintzel. His website address is He can be reached by e-mail at or by phone at 585-554-3313.

  5. Avatar of Karen Karen on October 25, 2018 at 1:47 am

    I usually use sheep minerals or pasture supplements made for sheep. I don’t know what the copper levels are in this area but there are copper mines in the southern Appalachian mountains within 100 miles of where I live. The souls are chronically acid because the rainfall washes most minerals out of the soul ( 60 inches a year) The souls are very high in iron as well. Once a year I get a deer or goat block which is 15 ppm copper. I have never had any issues. A fellow I know who used an advertised copper product for worm control in his sheep lost his entire herd because of it. He sued and won. I guess it depends a lot on the available copper in feedstuffs. I also free range my sheep and give about a cup of corn or no minerals added cattle feed to be them to come back to the barn at night.

    • Kelsie Raucher on October 26, 2018 at 1:30 pm

      Hi Karen,
      Thank you for sharing insight into your experience.

  6. Avatar of Bert Bert on October 27, 2018 at 6:27 pm

    I have a fairly large dorper flock and have in the past have had losses due to copper deficiency. I feed indoors silage based feeding program. I feed all the dry ewes a TM salt with selenium with 306mg/kg copper. My nursing ewes receive sheep mineral with no copper thinking that the elevated levels of copper will be passed to their young. I am very happy with the result and now know that sheep minerals simply do not have enough copper in it for my area.

  7. Avatar of Colson Colson on October 31, 2018 at 1:52 pm

    I have four your sheep 11 months old that came from a farm that is very high in Molybdemum and all sheep on that farm receive copper bolus twice a year. my sheep have never had one. they appear to be very anemic i.e. 4.5 on the Famacha chart though their fecal show minimal worm eggs. I am thinking that since they have never been given any copper that it might be the reason that they appear to be anemic. they have a 2.5 -3 body condition and seem to be happy and healthy. what are your thoughts.

    • Kelsie Raucher on November 7, 2018 at 2:11 pm

      Hi Colson,
      I would recommend reaching out to the author of the article, Ulf Kintzel, with your inquiry. He can be reached by e-mail at or by phone at 585-554-3313.

  8. Avatar of Tom Tom on November 24, 2019 at 6:22 am

    The penny would most likely pass through a sheep system before much of the copper surface corrodes. For some reason it does not, modern pennies are mostly zinc which can help counter the effects of copper poisoning.

  9. Avatar of Dianne Fitzmaurice Dianne Fitzmaurice on January 26, 2021 at 9:29 pm

    What is missing from this article is that copper needs to be in a balanced formula . It is the imbalances that create the troubles. The same with feeding any grains . Single grains also create imbalances. So the best thing I found was to feed a balanced formula sheep pellet and top it up in pregnancy with a balanced performance feed for pregnant and lactating animals that has a minimal amount of copper in balance with everything else. It is also especially necessary for heritage sheep to have copper. And this always did the job . Never any troubles on either way in 14 years with this balanced approach .

  10. Avatar of Ezra Ezra on March 1, 2021 at 9:31 pm

    This is great timing for this article (for me). I raise goats and sheep but they live together and have different requirements. Goats eat grass, bedding hay, garbage that blows in from the neighboring farms Rare), my pants if I don’t whack them and suck on the wire fence. They’re eat their tail if they could reach it just to see what it tastes like! The sheep are more discerning. But during the fattening phase for slaughter about a month of ‘Calf Creep’ which puts on weight and bulk but has trace copper. One month a year probably won’t hurt…especially since it’s the last month. My breeders get only grass year round and do fine.
    With just grass I get common twinning and 90-110lbs at the end of month nine for slaughter. That 45lb meat per and sweet gourmet mild lamb!

  11. Avatar of Mike Wallace Mike Wallace on October 3, 2021 at 5:29 pm

    There was a research report probably about 1988 +/- decade out of France I think. It showed r4esults of estimates of Cu rqmts and toxicities of diffferent breeds of sheep. Included Scandinavian (hi rqmt-tox) and Suffolk-Texel(die if they look at it). I may have a hard copy, but can’t5 find the srticle at home or on-line.
    BTW, I have seen PB Texels die from Cu tox that were fed-managed with FinnX tat were diagnosed as dying due to Cu def.

  12. Avatar of Leslie T Leslie T on October 31, 2021 at 11:59 am

    Really great article based on real life not some college study. Thank you a ton for writing this and posting it- having copper issues with my sheep and very hard to find any decent articles!

  13. Avatar of Mark Work Mark Work on December 1, 2021 at 12:22 pm

    Hi I wanted to know if 80 ppm of copper in deer feed is to much for my sheep? Thanks

  14. Avatar of Era Era on March 11, 2022 at 12:57 am

    I have never lost a sheep due to copper poisoning. I’m sure it IS possible but when I provided minerals specifically for sheep and specifically for goats in the same pasture it was remarkable how the various animals seemed to know what they needed. Very rarely did the sheep go to the goat dispenser but often enough that I realized they must need at least some.

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